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General Laboratory Safety Practices

The purpose of this guide is to promote safety awareness and encourage safe work practices in the laboratory. These are guidelines; they should serve as a reminder of things you can do to work more safely. Although these guidelines are applicable to all research, teaching and academic laboratories, your lab may require more specialized rules that apply to specific materials and equipment. Please see your Laboratory Supervisor (LS) or Principal Investigator (PI) for more information before beginning work in the lab.

Awareness

• Be alert to unsafe conditions and actions, and call attention to them so that corrections can be made as soon as possible.

• Label all storage areas, refrigerators, etc., appropriately, and keep all chemicals in properly labeled containers.
  • Date all bottles when received and when opened.

  • Note expiration dates on chemicals.

  • Note special storage conditions.

• Be familiar with the appropriate protective measures to take when exposed to the following classes of hazardous materials. Information is available from your lab supervisor, DES and the chemistry library:

  Flammables Radioactive Compounds Corrosives Biohazards

  Toxics Carcinogens Reactives Compressed Gases

• Segregate chemicals by compatibility groups for storage.

• Be aware of the potential interactions of lab furniture and equipment with chemicals used or stored in the lab. (e.g., are oxidizers stored directly on wooden shelving?)

• Post warning signs for unusual hazards such as flammable materials, biohazards or other special problems.

• Pour more concentrated solutions into less concentrated solutions to avoid violent reactions (i.e., Always add acid to water; not water to acid).

• Avoid distracting any other worker. Practical jokes or horseplay have no place in the laboratory.

• Use equipment only for its designated purpose.

• Position and secure apparatus used for hazardous reactions in order to permit manipulation without moving the apparatus until the entire reaction is complete.

Personal Safety

Respiratory and Body Protection

Use fume hoods whenever possible. Splash proof safety goggles should be worn at all times in the laboratory. Laboratory coat/apron should be worn in the laboratory. Appropriate gloves should be worn as needed. Appropriate closed-toed shoes should be worn in the laboratory. Respirators may only be worn by individuals that have completed respirator training and fit testing through DES and obtained a respirator medical clearance form the University Health Center.

Personal Hygiene

Wash hands before leaving laboratory. Launder clothing worn in laboratory separately from other clothing. Never mouth pipette anything in the lab. Never eat, drink or apply cosmetics in a laboratory or areas where chemicals/hazardous agents are stored. (Smoking is prohibited in all areas of University buildings, including laboratories.) Never store food in a refrigerator where hazardous materials are stored. Never eat or drink from laboratory glassware. Avoid wearing contact lenses in the laboratory. Avoid situating long hair, loose sleeves/cuffs, rings, bracelets, etc. in close proximity to open flames or operating machinery. Keep exposed skin covered. Shorts, sleeveless or short sleeve shirts, skirts or open-toed shoes should not be worn in the laboratory.

Fire Prevention

• Be aware of ignition sources in lab area (open flames, heat, electrical equipment).

• Purchase and store flammable reagents in the smallest quantities available.

• Store flammable liquids that require refrigeration in explosion-proof refrigerators.

• Store flammable liquids in appropriate safety cabinets and/or safety cans.

• Do not store incompatible reagents together (e.g., acids with flammables). Lists of incompatible reagents can be found in several source books (for example, Handbook of Reactive Chemical Hazards). See Appendix V for a table of some commonly-used laboratory chemicals and incompatibilities.

• Do not store ethers or conjugated dienes for extended periods of time as explosive peroxides could form. Date ethers when received and opened.

• Make sure that all electrical cords are in good condition. All electrical outlets should be grounded and should accommodate a 3-pronged plug. Never remove the grounding prong or use an adapter to bypass the grounding on an electrical cord.

• Remain out of the area of a fire or personal injury unless it is your responsibility to meet the emergency responders. Meet responders from a safe location.

• Be aware of the condition of fire extinguishers. Report any broken seals, damage, low gauge pressure or improper mounting to DES Fire Protection, (301) 405-3960. If the seal has been broken, assume that the fire extinguisher has been used and must be recharged. (Note: Do not use fire extinguishers unless you are trained and feel confident to do so.) Report ALL fires by phoning 911.

• Automatic fire sprinklers must remain clear and unblocked to function properly. Do not store materials within 18" below the sprinkler head.

Housekeeping

• Eliminate safety hazards by maintaining laboratory work areas in a good state of order.

• Maintain at least two clear passages to laboratory exits.

• Always keep tables, fume hoods, floors, aisles and desks clear of unnecessary material.

• Wipe down bench tops and other laboratory surfaces after each use with an appropriate cleaning or disinfecting agent.

• All equipment should be inspected before use.

• Use borosilicate glassware for laboratory work. If dichromate/sulfuric acid glass cleaner is used in your laboratory, make sure that cleaning is confined to the fume hood as toxic chromyl chlorides are released from the dichromate/sulfuric acid solution.

  Better yet, switch to a non-chromate cleaning solution. (i.e., No Chromix®) which will also minimize hazardous waste generation.

• If experiments must be left unattended, place a note next to experimental apparatus indicating the chemicals involved, your name and a number where you can be reached in case of an emergency.

• Keep the laboratory floor dry at all times. Immediately attend to spills of chemicals or water, and notify other lab workers of potential slipping hazards.

• All machinery under repair or adjustment should be properly tagged prior to servicing. All service work should be done by authorized personnel.

• Sink traps and floor drains should be flushed and filled with water on a regular basis to prevent the escape of sewer gases or the release of chemical odors in the event of an emergency. Drains which will not be routinely used may be "topped" with 20 - 30 ml of mineral oil to prevent evaporation of water in the trap.

• All compressed gas cylinders should be securely chained or clamped to a rack or fixed stationary piece of lab furniture. Mark empty cylinders, but use all safety precautions as if the cylinder were full.

Emergency Procedures

• In the event of an emergency, remember one number: 911. By calling this number, all necessary emergency response departments can then be alerted to your needs.

• Be familiar with the emergency evacuation plan.

• Be sure the names and phone numbers of lab personnel to be contacted in an emergency are posted in the lab or outside of the door.

• Be familiar with the location, use and limitations of the following safety devices:

  safety shower eye wash station protective respiratory gear fume hood

  spill cleanup materials first aid kit fire alarm fire extinguisher

• Clean up all small spills immediately. If a large chemical spill occurs, call the campus emergency phone number, 911. If the spill poses a hazard to individuals outside of the laboratory, follow the laboratory's emergency standard operating procedure. Stop current reactions or equipment if possible, activate the building fire alarm, exit the building, call 911 to report the emergency and stand by at a safe distance to provide information to emergency response personnel.

• If volatile, flammable, or toxic materials spill, shut off flames and spark-producing equipment at once and evacuate.

• In the event of fire or explosion, activate the building fire alarm, exit the building, call 911 to report the emergency and standby in a safe location to meet emergency responders.

• Do not cover windows of laboratory doors, except for special experimental requirements. This allows passers-by to notice if anyone is in need of emergency assistance.

• Maintain a clear path to all safety equipment at all times.

Waste Disposal

• Minimize Wastes at the source by limiting the quantities of materials purchased and used.

• Segregate and prepare chemical wastes for disposal in accordance with the procedures issued by DES. (See "UM Waste Disposal Guidelines" wall chart. Copies are available through DES at (301) 405-3960.)

• Dispose of all waste in designated containers. There are many different types of containers used at the UM for the collection of wastes. Know which ones are appropriate for the wastes you generate. Questions may be directed to Hazardous Waste Management, DES at (301) 405-3990 or (301) 405-3968.

Miscellaneous

• Children and pets should not be brought into the laboratory.

• If work is being conducted after hours, let other laboratory personnel know of your presence. If possible, avoid carrying out experimental laboratory work in an unoccupied building.

Safety Equipment

An expanding array of federal, state, and local laws and regulations make the protection of worker health and safety a legal requirement as well as an economic necessity. In the final analysis, personal and laboratory safety can be achieved only by informed, responsible individuals. This section summarizes various forms of personal and laboratory safety equipment. Based on this information, knowledgeable choices for appropriate personal protection in the laboratory can be made.

Personal Protective Equipment

Eye Protection	It is easy to take your senses for granted since they function without conscious thought. It's easy to relax your guard in the laboratory environment. After all, for those people not used to wearing glasses, it can be regarded as a burdensome task to wear unattractive, often restrictive eyewear. However, the chemical laboratory is likely to be the most health-threatening place that you can encounter. Splashing chemicals and flying objects are possible at any time in the lab environment. For this reason, eye protection is an important consideration. Protective eyewear for personnel and visitors should be splash proof. They must meet ANSI (American National Standards Institute) specifications. Approved eyewear usually bears an ANSI approval stamp on the lens or eye piece of the eyewear. If you don't have safety glasses, tell your supervisor. They can be purchased from any safety supply company, student supply stores or Chemistry Stores (located in room 0202 of the Chemistry Building, phone (301) 405-1838.)
Use and Maintenance	Eye wear should be as comfortable as possible, fit snugly over the eyes and around the face, and not interfere with the movement of the wearer. When it is appropriate, signs should be posted outside the door stating that eye protection is required before entering the room. Appropriate eye protection should be worn when using: caustics, corrosives, or irritants glassware under vacuum or pressure (reduced or elevated) cryogenic materials flammable materials radioactive materials explosives lasers (special lens protection required) UV light (special lens protection required) biohazards Eye protection should also be worn when performing these machine shop operations: welding sanding grinding drilling sawing Eye safety equipment should be capable of being cleaned and disinfected. Eye protection should always be kept in good condition.
Corrective Lenses	Laboratory workers whose vision requires the use of corrective lenses should wear safety eye protection of one of the following types: Prescription lens safety splash goggles. Splash-proof safety eye wear that can be worn over prescription glasses without disturbing the adjustment of the glasses.
Contact Lenses	Contact lenses should not be routinely worn in the laboratory. Laboratory personnel who must wear contact lenses while performing laboratory work should be aware of the following potential hazards: It may be impossible to remove contacts from the eyes following entry of some chemicals into the eye area. Contact lenses will interfere with emergency flushing procedures. Contacts may trap solid materials in the eyes. Use of contact lenses should be considered carefully, with extra consideration given to choosing eye protection that fits snugly over the eyes and around the face.

Protective Clothing

Lab Coat	The lab coat is designed to protect the clothing and skin from chemicals that may be spilled or splashed. It should always be properly fitted to the wearer and is best if it is knee length. There are several different types of lab coats for different types of protection. Cotton protects against flying objects, sharp or rough edges and is usually treated with a fire retardant. Wool protects against splashes of molten materials, small quantities of acid, and small flames. Synthetic fibers protect against sparks and infrared or ultraviolet radiation. However, synthetic fiber lab coats can increase the severity of some laboratory hazards. For instance, some solvents may dissolve particular classes of synthetic fibers, thereby diminishing the protective ability of the coat. In addition, on contact with flames, some synthetic fibers will melt. This molten material can cause painful skin burns and release irritating fumes. Aluminized and reflective clothing protect against radiant heat. The construction of the material must also be considered (twill, felt, plain, etc.), as the materials are rated differently by various manufacturers. Lab coats should be made with snaps/fasteners which afford the wearer quick removal in the event of an emergency.
Aprons	An apron provides an alternative to the lab coat. It is usually made of plastic or rubber to protect the wearer against corrosive or irritating chemicals. An apron should be worn over garments that cover the arms and body, such as a lab coat.

Foot Protection	Foot protection is designed to prevent injury from corrosive chemicals, heavy objects, electrical shock, as well as giving traction on wet floors. If a corrosive chemical or heavy object were to fall on the floor, the most vulnerable portion of the body would be the feet. For this reason, shoes that Completely Cover and Protect the foot are recommended.
	Fabric shoes, such as tennis shoes, absorb liquids readily. If chemicals happen to spill on fabric shoes, remove footwear immediately. When selecting footwear for the lab, choose sturdy shoes that cover the foot. These will provide the best protection. The following shoe types should not be worn in the laboratory: sandals clogs high heels shoes that expose the foot in Any Way The following are recommended types of footwear: Safety Shoes (steel-toed) protect against crushing injuries caused by impact from any object during work activities (e.g., lifting heavy objects, using power tools, etc.). Treated Shoes, Rubber Boots or Plastic Shoe Covers protect against corrosive chemicals. Insulated Shoes protect against electric shock. Rubber Boots with slip resistant outer soles provide traction in wet conditions where the possibility of slipping exists. Safety Shoes, Rubber Boots or Plastic Shoe Covers protect against specific types of chemical contamination and like gloves must be selected to match the current hazard.

Hearing Protection	DES will respond to inquiries regarding noise exposure in the work place. Upon request, the staff of DES will conduct environmental noise and/or personal exposure dosimetry. Ear protection should be worn where the noise level is above 85 decibels (dBA). Areas where excessive noise is present should be posted with signs indicating ear protection is required. Ear protectors should be readily available and rated for sufficient noise reduction. Contact DES for assistance in selecting appropriate hearing protection for your situation.
	Noise reduction ratings (NRR) for hearing protection products must be listed on hearing packaging. The NRR number is used in context of the following formula: Noise Dose in dBATWA8-(NRR-7) dBA = decibels on an A weighted scale TWA8 = eight hour time weighted average NRR = noise reduction rating. Types of ear protection include: Ear plugs provide basic protection to seal the ear against noise. Ear muffs provide extra protection against noise, and are more comfortable than ear plugs. Cotton inserts are poor suppressors of noise and should be avoided.

Head Protection

Some environments within UM have the potential for falling or flying objects. Appropriate head protection can protect laboratory workers from impacts, penetration by falling or flying objects, electric shock and burns. Unrestrained long hair can be hazardous. The use of caps, elastic bands or hair nets will prevent the hair from coming in contact with instrument/machinery parts, chemicals or flame-producing sources.

Respiratory Protection

Because certain laboratory procedures can produce noxious fumes and contaminants, respiratory protection may be required in your work environment. In fact, lab personnel noting changes in air quality should contact their LS/PI or DES, (301) 405-3960 and express their concerns. When engineering controls cannot successfully minimize or eliminate the potentially harmful fumes, a respiratory protection program should be established. Departments must refer individuals who need respiratory protection to DES for assistance in respirator selection, fit testing and training. A medical examination provided through the University Health Center is also required to assure the potential respirator wearer is physically capable of respirator use.

Laboratory Safety Equipment

Laboratory Chemical Fume Hood	Chemical fume hoods capture, contain, and expel emissions generated by hazardous chemicals. In general, it is a good idea to conduct all laboratory chemical experiments in a fume hood. While you may be able to predict the release of undesirable or hazardous effluents in some laboratory operations, "surprises" can always happen. Therefore, the fume hood offers an extra measure of protection. Before use, check to see that your hood has an inspection tag. This will tell you the date of the most recent hood evaluation. If the fume hood in your lab does not appear to be in good working order (a tissue, held inside the fume hood, can indicate if airflow is present), or if you have any questions, call DES. (Note: Do not allow tissues or other material to be pulled into the hood exhaust system as this may damage the unit or affect the air flow.) Certain laboratory procedures may require the use of perchloric acid. The use of this material may cause the formation of explosive perchlorate crystals. Special fume hoods, commonly known as Perchloric Acid Fume Hoods, MUST be used for this purpose. These hoods have self-contained wash-down units to inhibit crystal formation.
Operation	All laboratory workers with access to a laboratory chemical fume hood should be familiar with its use. Maintain the sash at or below the optimum operating height as designated by the label with an arrow. The optimum condition for general laboratory work in a chemical fume hood is between 80 and 125 fpm face velocity in a well installed unit. Radioactive materials use requires a face velocity of 100 fpm or greater at a minimum sash height of 12 inches. Higher face velocities often produce turbulence inside of the hood sufficient to eject contaminants into the laboratory. Raise large objects that must be in the hood (i.e., a water bath) to allow airflow beneath and on all sides of the object. Always work back into the hood, six inches beyond the sash line, keeping the sash line between your body and your work.
Maintenance	Keep the inside of the hood clean and uncluttered. The hood should always be in good condition and capable of routine use. Any hood or component of ventilation not properly functioning must be taken out of service and clearly tagged. The lab worker should not be able to detect strong odors released from materials in the hood. If odors are detected, check to make sure that the ventilation fan is turned on. If the fume hood is malfunctioning, discontinue work and call Facilities Management Work Control at (301) 405-2222. An emergency plan should exist in case of hood ventilation malfunction. All protective clothing should be worn when working with chemicals in the hood. In addition to gloves, safety glasses, and lab coats, a face shield or explosion shield will provide an extra measure of safety from reactive chemicals. Solid objects or materials should not be allowed to enter the exhaust ducts at the rear of the hood, as they can become lodged in the duct or fan. Fume hoods should not be used for long-term chemical storage.
Chemical Storage Cabinets	Storage of flammables and corrosives in the lab should be limited to as small a quantity as possible. Flammable materials should be stored in flammable material storage cabinets which meet OSHA 1910.106d and NFPA 30 specifications. These specifications are available from DES.
Use and Maintenance	Chemicals should Never be stored in alphabetical order without consideration for chemical compatibilities. This system may contribute to the probability of incompatible materials being stored next to one another (e.g., butadiene next to bromine or chlorine). Incompatible reagents should not be stored next to each other. (See the chemical incompatibility chart in the appendices of this manual.) Storage outside of the cabinet should be limited to materials used in the current process. The vent cap on chemical storage cabinets should not be removed unless the cabinet is attached to an approved ventilation system. If a cabinet is connected to a ventilation system, the connection must either have a thermally actuated damper or sufficient insulation on the vent piping to avoid compromising the fire protection ability of the cabinet. Glass containers should be stored on the bottom shelf of storage cabinets.
Types of Cabinets	Flammable liquid cabinets are designed for storage of flammable or combustible liquids. Acid/corrosive cabinets are designed for corrosion resistance. Bulk storage cabinets can be used for storage of flammable and corrosive liquids outside the laboratory setting.
Individual Storage Containers	Selecting the best means of storage for chemical reagents will, to a great extent, depend on that reagent's compatibility with the container.
	A safety can is an approved container of no more than five gallons (19 liters) capacity. It has a spring-closing lid and spout cover, and is designed to safely relieve pressure buildup within the container. Vent caps may be purchased for original manufacturers' glass containers to help minimize explosion hazards.
Refrigerators	While domestic refrigeration units are appropriate for keeping foods cold, they are not designed to meet the special hazards presented by flammable materials. Therefore, laboratory refrigerators should be carefully selected for specific chemical storage needs. To prevent potential safety hazards, the length of storage of any material should be kept to a minimum. In addition, refrigerators should be periodically inspected. Refrigerators used to house flammable materials must be approved for such use by FM® (Factory Mutual) or UL® (Underwriters Laboratory).
Use and Maintenance	Each refrigerator, freezer or other cooling unit should be prominently labeled with appropriate hazard signs to indicate whether it is suitable for storing hazardous chemicals. Label chemical hazard refrigerators with the sign "For Chemical Storage Only. No Food or Drink Allowed." If radioactive materials are to be stored, a refrigerator must be clearly labeled "Caution, Radioactive Material. No Food or Beverages May Be Stored in This Unit." The containers placed in the refrigerator should be completely sealed or capped, securely placed, and labeled. Avoid capping materials with aluminum foil, parafilm, corks, and glass stoppers. Refrigerators should be frost free to prevent water drainage.
Types of Refrigerators	Because ignitable vapors can build up in refrigerators, it is important to store flammable and combustible materials in specially-designed units. These refrigerators will have self-contained electrical elements to avoid spark-induced explosions. Explosion-proof or intrinsically safe refrigerators are specifically designed for hazardous environments, featuring enclosed motors to eliminate sparking and bear a FM or UL explosion-proof label. Highly volatile flammable and combustible substances that require refrigeration may be stored only in explosion-proof refrigerators especially designed for such use. Such refrigerators must meet the requirements for Class 1 Division 1 Electrical Safety Code (NPFA 70 and NFPA 45) and require direct wiring to the power source via a metal conduit. The same storage requirements apply to any solution or specimen that may release flammable fumes (e.g., the ether-impregnated fur of a dead rat has been known to cause an explosion in a refrigerator).
Eyewash Stations	Eyewash stations provide an effective means of treatment when chemicals come in contact with the eyes. Eyewash stations should be readily available and accessible to all laboratory personnel.
	The eyewash facility should be clearly marked and no more than 100 feet, or 10 seconds, away from every lab work station. Laboratory workers should be able to locate the nearest eye wash facility with their eyes closed (eye injuries may involve temporary blindness). An eye injury usually accompanies a skin injury. For this reason, eye wash stations should be located near the safety shower and/or drench hose so that eyes and body can be washed.
Use and Maintenance	Water/eye solutions should not be directly aimed onto the eyeball, but rather, aimed at the base of the nose. This increases the chance of effectively rinsing the eyes free of chemicals (harsh streams of water may drive particles further into the eyes). Eyelids may have to be forcibly opened to attempt eye rinse. Flood eyes and eyelids with water/eye solution for a minimum of 15 minutes. Remove contact lenses as soon as possible to rinse eyes of any harmful chemicals. Eye wash stations should be drained and tested weekly by laboratory personnel and inspected every six months.
Types of Eye Wash Stations	Gravity Feed - Self Contained provides the laboratory worker with emergency eye wash treatment in areas inaccessible to plumbing. Faucet-mounted (pin or push plate activators) provides continuous water flow while freeing hands to open eyelids. It turns a standard faucet into a practical emergency eye wash station. Laboratory Bench sprays with squeeze handles can be installed through the bench top for instant availability, but does not satisfy OSHA requirements as an accessible eyewash. Swivel Eye Wash mounts on lab bench or counter top adjacent to a sink. It swivels 90 over the sink for use, or out of the way for storage. Bowl-mounted (pin, push plate or foot pedal activators) provides continuous water flow through a free-standing plumbed unit. The bowl may be directed to a floor drain or connected directly to a sewer connection for easy testing and use.
Safety Showers	Safety showers provide an effective means of treatment in the event that chemicals are spilled or splashed onto the skin or clothing. Safety shower facilities should be installed wherever corrosive chemicals are used (e.g. acids or alkalis) and must be readily available to all personnel.
Use and Maintenance	Safety showers should be in a clearly marked location. The facility should be no more than 100 feet, or 10 seconds, away from every lab work bench. Laboratory workers should be able to locate the shower(s) with their eyes closed (emergency situations may leave victims temporarily blind). Safety showers are operated by grasping a ring chain or triangular rod. The pull mechanism is designed for people of most heights but may require a modification for wheelchair access. It should always be accessible and hang freely. Safety showers should supply a continuous stream of water to cover the entire body. Individuals should remove contaminated clothing, including shoes and jewelry, while under an operating shower. Safety showers should be located away from electrical panels or outlets. If at all possible, safety shower facilities should be installed near appropriate drainage systems.
Types of Safety Showers	Ceiling/Wall Emergency Shower provides a continuous water flow and mounts directly to overhead vertical pipes or horizontal wall pipes. Floor-Mounted Emergency Combination eye wash/face and body wash mounts directly to horizontal pipes. Deck-Mounted Drench Hose is a hand operated unit intended to augment a safety shower for quick spot-washing of injuries.
Fire Safety Equipment
Types of Equipment	Fire Alarms are designed so that all endangered laboratory personnel and building occupants are alerted by an audible warning (in many buildings there is also visual warning). Fire alarm systems are not monitored at a remote location. Fire alarm activations must be reported to Emergency Assistance (911) from a safe location. All employees/students should become familiar with the Exact Location of the fire alarm pull stations nearest to their laboratory. Sprinkler systems, smoke detectors and heat detectors may automatically activate the fire alarm. (This should not be considered a substitute for manual fire alarm activation.) Fire Extinguishers are spaced and located as required by current fire codes and standards. Multipurpose fire extinguishers can be found in hallways and near exits in most laboratories. Additional or redundant extinguishers will only be provided at a charge to the requestor (Note: Special purpose fire extinguishers are provided where necessary). Only use a fire extinguisher if the fire is very small and you know how to use the extinguisher safely. If you can't put out the fire, leave immediately. Make sure the fire department is called even if you think the fire is out. In laboratories, fire extinguishers should be securely located on the wall near an exit. The lab occupant should be aware of the condition of the fire extinguishers by observing them for broken seals, damages, low gauge pressure, or improper mounting. DES Fire Protection performs annual maintenance on all fire extinguishers. The last month and year that maintenance was performed is indicated on a tag or sticker on the extinguisher. Occupants of labs should visually inspect lab fire extinguishers at least monthly. Units that are missing, have broken seals, low pressure or visible damage should be reported to DES Fire Protection immediately for replacement. For fire extinguisher service, requests, training, or any questions call DES Fire Protection at (301) 405-3960. Sprinklers are designed to enhance life safety by controlling a fire until the fire department arrives or, in many cases, completely extinguishes a fire. Sprinklers are automatically activated, and laboratory workers should not attempt to shut off or tamper with the system. Items in the laboratory must be stored at least 18 inches below the sprinklers. Items (e.g., wiring or tubing, etc.) must not hang from the sprinklers or sprinkler pipes. Sprinklers must not be painted or otherwise obstructed. Intense heat should not be used near sprinklers. If there are any questions on fire safety equipment call DES Fire Protection at (301) 405-3960. Call Work Control Center, (301) 405-2222, to report damage to fire alarm or sprinkler systems.

Laboratory Equipment Safety

Glassware	Accidents involving glassware are a leading cause of laboratory injuries. These can be avoided by following a few simple procedures. In general, be certain that you have received proper instructions before you use glass equipment designed for specialized tasks that involve unusual risks or potential injury. Listed below are some safety rules.
Use and Maintenance	Handle and store glassware carefully so as not to damage it or yourself. Properly discard or repair damaged items. When inserting glass tubing into rubber stoppers, corks or when placing rubber tubing on glass hose connections: protect hands with a heavy glove or towel lubricate tubing or stopper with water or glycerol and be sure that the ends of the glass tubing are fire-polished hold hands close together to limit movement of glass should fracture occur substitute plastic or metal connections for glass ones whenever possible to decrease the risk of injury use glassware designed for vacuum work for that purpose when dealing with broken glass wear hand protection when picking up the pieces use a broom to sweep small pieces into a dustpan package it in a rigid container (i.e. corrugated cardboard box) and seal to protect personnel from injury. Never attempt glass-blowing operations without proper facilities.
Heating Devices	Electrical devices that supply heat for reactions or separations are commonly used in laboratories. Electrically heated devices include: hotplates; hot-tube furnaces; heating mantles; hot-air guns; oil baths; ovens air baths; Improper use could result in fire or burns to the user.
Use and Maintenance	If baths are required to be activated when not attended, they should be equipped with timers to turn them on and off at suitable hours and, if possible, a thermostat to turn off power if the unit overheats. Flammable or combustible solvents should never be used in a heated bath unless housed in a chemical fume hood. Before using any heating device: check to see if the unit has an automatic shutoff in case of overheating; note the condition of electrical cords and have them replaced as required; make sure the apparatus has been maintained as required by the manufacturer; make sure the device maintains a Underwriters' Laboratories (UL®) or Factory Mutual Engineering Division of Associated Factory Mutual Fire Insurance Companies (FM®) listing; check to see that all heating units in use without automatic shut-off have been turned off before leaving an area for any extended period of time.
Vacuum Systems
Use and Maintenance	Every laboratory vacuum pump must have a belt guard in place when it is in operation. The service cord and switch, if any, must be free of observable defects. Use a trap on the suction line to prevent liquids from being drawn into the pump. If vapors are being drawn through the pump, a cold trap (which is a tube that will condense vapors passing through it) should be inserted in the suction line to prevent contamination of the pump oil. Place a pan under the pump to catch any oil drips.
Explosion Prevention	In order to prevent explosions:
If the Pump is Used... You Must... for vacuum distillation or filtration of organic liquids direct the discharge to an operating hood or other exhaust system. discharge into an enclosed space such as a cabinet can cause explosion. in an area where flammable gas, vapor, or dust are present. ensure that the motor, cord, plug, and all electrical parts are explosion-proof.
Glassware	Glassware used for vacuum distillations or other uses at reduced pressure must be properly chosen for its ability to withstand the external pressure of the atmosphere. Only round-bottom vessels may be subjected to vacuum unless specially designed, such as Erlenmeyer-type filtration flasks. Each vessel must be carefully inspected for defects such as scratches or cracks.
	All vacuum operations must be carried out behind a table shield or lowered fume hood sash because all vacuum equipment is subject to failure by implosion. (Implosion occurs when atmospheric pressure propels pieces inward creating small fragments which are subsequently propelled outward with considerable force.) Dewar vessels have a vacuum between the walls and some types can be dangerous when they fail. Glass types can propel glass into the eyes and should be wrapped from top to bottom with cloth tape such as electrician's friction tape. (Mylar tape can be used if transparency is needed.) Large Dewars encased in metal and stainless steel vacuum containers do not require wrapping. Glass desiccators are often subjected to partial vacuum due to cooling of the contents. Due to glass thickness and the relatively flat surface of the top and bottom, the desiccator is under a constant tension. It is strongly recommended that you either: obtain the available desiccator guard made of perforated metal, or use a molded plastic desiccator which is spherical and has high tensile strength.
Centrifuges
Use and Maintenance	Do not attempt to operate a centrifuge until you have received instruction in its specific operation. Read the operation manual, if available, and ask an experienced colleague to demonstrate procedures. Individual users are responsible for the condition of the centrifuge machine and rotors during and at the end of procedures. This responsibility includes proper loading, controlling speed to safe levels, safe stopping, removal of materials, and cleanup. Ultra centrifuge rotors require special cleaning procedures to prevent scratching of surfaces, which can lead to stress points and possible rotor failure during operation. In selecting a centrifuge, carefully consider: location, type, and use balance capability each time the centrifuge is used adequate shielding against accidental "flyaways" suction cups or heel brakes to prevent "walking" accessibility of parts, particularly for rotor removal lid equipped with disconnect switch which shuts off rotor if the lid is opened safeguard for handling flammables and pathogens. (This may include positive exhaust ventilation, a safe location or sealed cups.) positive locking of head electrical grounding locations where vibration will not cause bottles or equipment to fall off shelves
Potential Problems to Watch For Problem Effect Precaution Against Unbalanced load Damage to seals or other parts Keep lid closed during operation and shut down and stop the rotor if you observe anything abnormal, such as: --noise --vibration Broken tubes Centrifuge contamination and personal injury When loading the rotor: --examine tubes for signs of stress --discard tubes that look suspicious

First Aid and Emergency Procedures

The first aid and emergency procedures detailed in this section could be life-saving. Become familiar with the information described below, so that disasters can be speedily contained. It is the responsibility of the injured employee or student to report bodily injury or property damage to DES at (301) 405-3964 even if a police report is filed. Supervisors of injured employees must complete the "Workers Compensation Employer's First Report of Injury or Illness" form to report on-the-job injury. Required forms and instructions will be provided to the injured individual by the University Health Center at the time of initial visit to be returned to their supervisor for completion. If treatment is obtained at a location other than the University Health Center, it is the employee's responsibility to obtain the compensation forms from the University Health Center, complete the forms and return them to the University Health Center. For more information concerning Workers' Compensation contact the Health Center at (301) 314-8171.

Wounds	Small cuts and scratches Direct pressure -- place sterile pad over wound and apply pressure evenly with the opposite hand. Elevation -- if direct pressure does not control bleeding, raise the area above the level of the heart. Cleanse area with soap and water. Significant bleeding Call Emergency Rescue (911). Direct Pressure -- place sterile pad over wound and apply pressure evenly with the opposite hand. Elevation -- if direct pressure does not control bleeding raise the area above the level of the heart.
Thermal Burns	First degree burns (e.g., sunburn or mild steam burn) are characterized by redness or discoloration of the skin, mild swelling and pain. First Aid procedures for first degree burns are as follows: Apply cold water applications and/or immerse in cold water for at least 10 minutes. Seek further medical treatment as needed. Second and third degree burns are characterized by red or mottled skin with blisters (second degree), white or charred skin (third degree). First aid procedures for second and third degree burns are as follows: Call Emergency Rescue (911). area in clean, dry material.
Chemical Burns	If hazardous chemicals should come into contact with the skin or eyes, follow the first aid procedures below. Skin Remove victim's clothes -- don't let modesty stand in the way. Remove victim's shoes -- chemicals may also collect here. Rinse the area with large quantities of water for at least 15 minutes (sink, shower, or hose). Do Not apply burn ointments/spray to affected areas. Call Emergency Rescue (911) without delay. Eyes (acid/alkali, e.g., HCl, NaOH) Call Emergency Rescue (911) without delay. Rinse area of eyes, eyelids, and face thoroughly with lukewarm water for at least 15 minutes at the eye wash station.
Ingestion of Chemicals	Call Emergency Rescue (911) Immediately. Call the University Health Center Urgent Care at (301) 314-8162 or Maryland Poison Center at 1-800-492-2414 for advice on appropriate actions to be taken while awaiting emergency medical assistance. If the victim is unconscious, turn their head or entire body onto their left side. Be prepared to start CPR if you are properly trained, but be cautious about exposing yourself to chemical poisoning via mouth-to-mouth resuscitation. If available, use a mouth-to-mask resuscitator.
Inhalation of Chemicals	Evacuate the area and move the victim into fresh air. Call Emergency Rescue (911) without delay. If the victim is not breathing and you are properly trained, perform CPR until the rescue squad arrives. Be careful to avoid exposure to chemical poisoning via mouth-to-mouth resuscitation. Use a mouth-to-mask resuscitator. Treat for chemical burns of the eyes and skin as noted above.

First Aid Kits

First aid kits should be standard equipment in every laboratory. Commercial, cabinet-type, or unit-type first aid kits are acceptable. A typical first aid kit for laboratories includes a variety of items specially selected to carry out emergency treatment of cuts, burns, eye injuries, or sudden illness. The first aid kit should contain individually sealed packages for each type of item. Contents of the kit should be checked weekly to ensure that expended items are replaced. Laboratory supervisors are responsible for maintaining the contents of the first aid kit. Kits are available from most general safety or lab supply houses. For assistance in locating a supplier call Campus General Stores at (301) 405-7337 or (301) 405-5854.

No oral medication (including aspirin) should be dispensed from the first aid kit.

CPR Training for adults, children and infants is available to all faculty, staff and students at a nominal charge from the University Health Center CPR Training Center. For registration information or a class schedule call the CPR Training Center at (301) 314-8132.

Emergency Procedures

Note: Emergency assistance for all types of emergencies may be obtained 24 hours a day by dialing the emergency assistance number, 911, from any campus or off campus phone or by simply picking up the receiver of any emergency phone on campus. Emergency phones inside of campus buildings are yellow. Outside emergency phones may be recognized by blue lights above the telephone. Emergency telephones only reach the emergency dispatcher and may not be used to reach other local or campus numbers. If you must use a pay phone in an emergency, you may dial 911 without inserting a coin.

Chemical Spills	General Safety Guidelines. The procedures described below are to be used for small chemical spills where materials for clean-up are available in the lab and if employees have received training in their use. For larger spills call the campus emergency phone number at 911. When unsure of how to clean up small amounts of a material, notify your supervisor or call DES at (301) 405-3960. See the "UM Hazardous and Regulated Waste Management Plan" for more information. Locate spill cleanup materials. Laboratories should be equipped with spill cleanup kits. If your laboratory area does not have such emergency items, the supervisor can contact DES for assistance in obtaining the appropriate material. Wear the appropriate personal protective equipment (e.g., gloves, goggles) when cleaning up spills. Acid Spills Apply neutralizer (or sodium bicarbonate) to perimeter of spill. Mix thoroughly until fizzing and evolution of gas ceases. Note: It may be necessary to add water to the mixture to complete the reaction. Neutralizer has a tendency to absorb acid before fully neutralizing it. Check mixture with pH indicator paper to assure that the acid has been neutralized. Transfer the mixture to a plastic bag, tie shut, fill out a waste label, and place in the fume hood. Notify supervisor or call DES for disposal. Caustic Spills Apply neutralizer to perimeter of spill. Mix thoroughly until fizzing and evolution of gas ceases. Check mixture with pH indicator paper to assure that the material has been completely neutralized. Transfer the mixture to a plastic bag, tie shut, fill out a waste label, and place in the fume hood. Notify supervisor or call DES for disposal. Solvent Spills Apply activated charcoal to the perimeter of the spill. Mix thoroughly until material is dry and no evidence of liquid solvent remains. Transfer absorbed solvent to a plastic bag (if compatible), tie shut, fill out and attach a waste label, and place in the fume hood. Notify supervisor or call DES for disposal. Mercury Spills Using a mercury vacuum available through DES, vacuum all areas where mercury was spilled with particular attention to corners, cracks, depressions and creases in flooring or table tops. Call DES for mercury vacuum delivery or pick-up. To clean up small spills with a mercury spill kit, dampen the mercury sponge with water, then wipe the contaminated area. Do this procedure slowly to allow for complete absorption of all free mercury. A silvery surface will form on the sponge. Place the contaminated sponge in its plastic bag, tie shut, fill out and attach a waste label, and place in the fume hood. Notify supervisor or call DES for disposal. For larger spills that cannot be cleaned up by lab occupants, call DES Hazardous Waste Management at (301) 405-3968 or the campus emergency number (911).
Radioactive Material Spills	In the event of any occurrence out of the ordinary involving radioactive materials or radiation producing equipment see the radiation emergency procedures guide located on page 33 of the "Radiation Safety Manual" (reprinted in the Appendix III of this document) and contact the Radiation Safety Officer (RSO) via the campus emergency number (911). If contaminated, do not leave the area of the spill until you are decontaminated by DES Radiation Safety unless you have serious injury. Any event involving radioactive materials must be reported to the RSO as some circumstances require immediate notification to State Authorities.
Biohazard Spills	Appropriate personal protective measures must be taken for cleanup of potentially-infectious wastes. Laboratories using infectious agents should be certified at the appropriate biosafety level as defined by the Centers for Disease Control and Prevention - National Institutes of Health by the UM Biosafety Officer (BSO) through the Biological and Chemical Hygiene Committee (BACH). Procedures for containing and cleaning up spills of infectious agents will be reviewed and approved by the BSO as part of the certification process. Contact the UM BSO at (301) 405-3960 for more information or to schedule an appointment. See the UM "Bloodborne Pathogens Exposure Control Plan" or call DES for more information.
Fire Safety
Written Plan	Laboratory supervisors must be knowledgeable of the UM Policy Concerning Fire Emergencies (see Appendix VI). This official policy describes the procedures occupants must take in the event of fire or other emergencies. Laboratory supervisors should develop a plan which incorporates specific instructions relating to their laboratories into the UM Policy Concerning Fire Emergencies. Specific instructions should include: Location of exits and emergency escape routes. Locations of fire alarm pull stations and emergency phones. Operations to be shut down, turned off or secured before evacuation without placing personnel in danger. A location for laboratory personnel to meet and the procedure to account for personnel after an evacuation. Laboratory supervisors should review the plan with new employees and students and annually with all personnel. The laboratory-specific fire emergency plan should be posted in the laboratory. DES Fire Protection can assist in developing a plan, call (301) 405-3960.
Small Laboratory Fires	Small fires which are contained in beakers or flasks can be extinguished by covering the fire with a larger beaker if the laboratory personnel are confident to do so. Do Not attempt to fight a fire that cannot be extinguished immediately by covering with a larger beaker. Initiate the fire emergency procedures located in Appendix VI.
Individual on Fire	The rescuer should instruct the victim to Stop - Drop - Roll. Victims should also place their hands over their face. The victim should Not run to a fire blanket. If a fire blanket is available, it may be used by a rescuer to smother the flames. Do Not use fire extinguishers to extinguish a person that is on fire. Do Not attempt to remove clothing from burned areas. Call for emergency assistance (911) immediately. Do Not put water on large burns. Keep burned areas clean and dry. Keep victim calm. For information or questions on fire emergency procedures, call the DES Fire Protection at (301) 405-3960.

Properties of Hazardous Chemicals

Flammability

Flammability is a measure of how easily a gas, liquid, or solid will ignite and how quickly the flame, once started, will spread. The more readily ignition occurs, the more flammable the material. Flammable liquids themselves are not flammable; rather, the vapor from the liquids are combustible. There are two physical properties of a material which indicate its flammability: flash point and volatility (boiling point).

The flash point of a material is the temperature at which a liquid (or volatile solid) gives off vapor in quantities significant enough to form an ignitable mixture with air. Given an external source of ignition (i.e., spark, flame), a material can ignite at temperatures at or above its flash point. The flash point of ethyl ether, a highly flammable solvent, is -49F. Kerosene has a flash point between 100F and 150F. Flammable gases have no flash point, since they are already in an ignitable form.

The volatility of a material is an indication of how easily the liquid or solid will pass into the vapor stage. Volatility is measured by the boiling point of the material -- the temperature at which the vapor pressure of the material is equal to the atmospheric pressure. The term volatility is often mistakenly used as a synonym for flammability. There are some materials that are volatile but not flammable such as water, chloroform and mercury.

Some materials are pyrophoric, meaning that they can ignite spontaneously with no external source of ignition. Potassium metal, for example, can react with the moisture in air. This reaction causes hydrogen gas to be evolved, and the heat generated by the reaction can be hot enough to ignite the hydrogen.

	Flammability (degree F)		Max. Size per Container Type				Max. QTY perR
	Flash Point	Boiling Point	Glass	Metal	Plastic	Safety Can*	Flammable Cabinet**
Flammable Liquids
Class IA	below 73	below 100	1 pt.	1 gal.	1 gal.	2 gal.	60 gal.
Class IB	below 73	above 100	1 qt.	5 gal.	5 gal.	5 gal.	60 gal.
Class IC	73 - 100	N/A	1 gal.	5 gal.	5 gal.	5 gal.	60 gal.
Combustible Liquids
Class II	100 - 140	N/A	1 gal.	5 gal.	5 gal.	5 gal.	60 gal.
Class IIIA	140 - 200	N/A	5 gal.	5 gal.	5 gal.	5 gal.	120 gal.
Class IIIB	> 200	N/A	5 gal.	5 gal.	5 gal.	5 gal.	N/A

* U.L. Approved
** Max. 3 cabinets per fire area
A maximum of 10 gal. of class I and/or II liquids may be stored in any fire area outside of safety cans.
A maximum of 25 gal. of class I and/or II liquids may be stored in any fire area inside of safety cans.

Handling	Use gloves and splash-proof safety goggles when handling flammable liquids. Mixtures of flammable or combustible liquids should be treated as though the mixture had the lowest flash point represented. Dispensing of flammable or combustible liquids should only be carried out under a fume hood or in an approved storage room. When transferring or using a flammable liquid, all ignition sources should be eliminated from the area. Open flames or hot plates should not be used to directly heat flammable liquids. Do Not use water to clean up flammable liquid spills. Do Not dispose of flammable or combustible liquids in the sink or drain. Follow disposal procedures issued by DES in the "UM Hazardous and Regulated Waste Management Manual". "No Smoking" signs should be posted where flammable liquids are being handled.
Corrosivity
	Gases, liquids, and solids can exhibit the hazardous property of corrosivity. Corrosive materials can burn, irritate, or destructively attack skin. When inhaled or ingested, lung and stomach tissue are affected. Corrosive gases are readily absorbed into the body through skin contact and inhalation. Corrosive liquids are frequently used in the laboratory and have a high potential to cause external injury to the body. Corrosive solids often cause delayed injury. Because corrosive solids dissolve rapidly in moisture on the skin and in the respiratory system, the effects of corrosive solids depend largely on the duration of contact. Materials with corrosive properties can be either acidic (low pH) or basic (high Ph). Examples of corrosives are listed below: sulfuric acid hydrochloric acid nitric acid ammonium hydroxide sodium hydroxide chromium trioxide
Labeling & Information	The corrosive label normally depicts the corrosion of a hand and bar of steel. Information on corrosivity can be found in the MSDS under Health Effects and First Aid.
Storage	Segregate acids from bases, and corrosive materials from both organic and flammable materials. Store corrosive materials near the floor to minimize the danger of falling from shelves. Store in cool, dry, well-ventilated areas and away from sunlight. The storage area should not be subject to rapid temperature changes.
Handling	Wear adequate protective equipment (lab apron, appropriate gloves and splash-proof eye protection). If splashing is a definite hazard, face shields must also be worn. Corrosive materials should be handled in a fume hood to protect the user from the possible generation of hazardous or noxious fumes. Add reagents slowly. Always add acids to water (never water to acid). During the addition of reagents, allow acid to run down the side of the container and mix slowly. Corrosive materials should be transported in unbreakable containers. For cleaning corrosive spills, refer to Emergency Procedures.
Reactivity
Explosives	Explosive materials are chemicals that cause a sudden, almost instantaneous release of large or small amounts of pressure, gas and heat when subjected to sudden shock, pressure or high temperature. Some substances, under certain conditions of shock, temperature or chemical reaction, can explode violently. Such explosions present many hazards to laboratory personnel. flying glass can seriously lacerate skin fires can result from burning gases corrosive or toxic substances can be liberated Before working with explosive materials, understand their chemical properties, know the products of side reactions, the incompatibility of certain chemicals, and monitor possible environmental catalysts (such as temperature changes). Examples of materials that may be explosive under some conditions of use: acetylene azide hydrogen nitro compounds ammonia organic peroxides perchlorates bromates
Labeling & Information	Information on explosives can be found on the MSDS under Fire and Explosion Data.
Storage & Handling	Explosion hazards. Avoid: allowing picric acid to dry out mixing flammable chemicals with oxidants flammable gas leaks heating compressed or liquefied gas uncontrollable or fluctuating temperatures during experiments using explosive chemicals bringing hot liquid (e.g., oil) into sudden contact with a material possessing a lower boiling point contacting flammable materials with catalysts (e.g., acids or bases catalyze an explosive polymerization of acrolein) explosive peroxide generation products that build up in solvent containers during storage mixing nitric acid with acetone distilling ethers unless free from peroxides Carefully plan a procedure for working with explosive materials. Insert experimental apparatus into a dry glove box or gas blanket. Minimize storage of ethers. Keep specified fire extinguishing equipment near the explosive chemical workspace. Determine all explosive hazards prior to experimental work, including the stability of reactants/products. For more information, contact DES at (301) 405-3960.
Oxidizers
	An oxidizing agent is a chemical used to provide oxygen for chemical reactions. Oxidizers spontaneously evolve oxygen at room or slightly elevated temperatures, and can explode violently when shocked or heated. Because they possess varying degrees of chemical instability, oxidizing agents are explosively unpredictable and, therefore, represent a particularly hazardous safety threat. Examples of oxidizing agents: peroxides hyperperoxides peroxyesters Oxidizers can react violently when in contact with organics. For this reason, avoid interactions between oxidizers and organic materials. Examples of organic-reactive oxidizers include nitric acid, chromic acid, and permanganates.
Peroxides	Some organic compounds, such as ethers, can react with oxygen from the air, forming unstable peroxides. Peroxide formation can occur under conditions of normal storage, when compounds become concentrated by evaporation, or when mixed with other compounds. The accumulated peroxides can then violently explode when exposed to shock, friction, or heat. Pure compounds will accumulate peroxides more readily than compounds containing impurities. Examples of organic compounds that form hazardous peroxides: aldehydes, ketones ethers compounds with allylene (CH2 = CHCH2R) structure alkali metals, alkoxides, amines vinyl and vinylidene compounds compounds with benzylic hydrogen atoms Examples of chemicals which form hazardous peroxides during exposure to air: ethyl vinyl ether p-Dioxane decalin ethyl ether tetralin isopropyl ether tetrahydrofuran (THF) Destruction of the listed chemicals is recommended within 1 year of chemical receipt or 1 month after opening without any testing for peroxide content.(1) (1)Accident case Histories, Chemical Manufacturers Association, Washington, DC, 1971. No. 1693 as reprinted in Improving Safety in the Chemical Laboratory, Ed. Jay Young, John Wiley & sons, Inc., NY, 1991, pg. 116. Acetal Diethyl ether Allyl ether Diethyl fumarate Allyl phenyl ether Dioxane Isoamyl benzyl ether 1,3-Dioxepane Benzyl n-butyl ether 1,2-Epoxy-3-isopropoxypropane Dibenzyl ether Benzyl ethyl ether Isophorone Benzyl 1-naphthyl ether Dimethoxymethane p-Dibenzyloxybenzene 2,2-Dimethoxypropane 1,2-Dibenzyloxyethane 1,3,3-Trimethoxypropene Chloroacetaldehydediethylacetal Di-n-propoxymethane 2-Chlorobutadiene beta-Isopropoxyproprionitrile Cyclohexene Diisopropyl ether Cyclooctene n-Propyl isopropyl ether Decalin Tetralin Diethoxymethane Vinylidene chloride Discard opened containers of peroxidizable compounds not listed above within 12 months or minimum expiration date provided by the manufacturer if less than 12 months. For disposal, call DES at (301) 405-3960.
Labeling & Information	A pictorial oxidizer label depicts a flaming letter "O" on a yellow background. Information on oxidizing agents can be found on the MSDS under the heading Reactivity Data.
Storage & Handling	Order ether in small quantities and use quickly. Include the date of purchase on containers of peroxidizable compounds. Note the date of opening on the label. When possible, store peroxidizable compounds (except certain inhibited vinyl monomers) under a nitrogen atmosphere. Keep away from heat, light, and ignition sources. Store in a cool, dry, well-ventilated area, out of direct sunlight. Protect from extreme temperatures and rapid temperature changes. Do Not Smoke near oxidizers. Store in amber glass or inert containers, preferably unbreakable. Containers should be tightly sealed. Do Not use corks or rubber stoppers to cap containers. Before opening glass bottles, look for the presence of solids (crystals) or viscous liquid at the bottom of the bottle. These are good indicators of peroxide formation. Do not open a container that is suspect -- call DES at (301) 405-3960 for disposal. Isolate reactive chemicals from incompatible materials. organic materials flammable solvents corrosives (i.e., nitric, chromic acids) Avoid friction, grinding and all forms of impact while working with oxidizers. Avoid mixing oxidizing agents with other chemicals during disposal procedures. To detect the presence of peroxides, the following procedure can be used. In a 25ml glass-stoppered cylinder (colorless, protected from the light), add 1 ml of freshly prepared 10% aqueous potassium iodide solution to 10 ml of organic solvent. View the cylinder transversely against a white background. If a yellow or brown color appears, peroxide is present. Call DES for disposal. For more information, contact DES at (301) 405-3960.
Toxicity
	The concept of toxicity is unique because it can be applicable to all chemical substances used in the laboratory. The terminology explained below can assist laboratory workers in assessing the degree of hazard and provide guidance in the selection of appropriate personal protective equipment. Toxicity is defined as the ability of a substance to cause: damage to living tissue, impairment of the central nervous system, severe illness, or in extreme cases, death when ingested, inhaled, or absorbed through the skin. The administration of a particular dosage of a chemical, and the subsequent response by experimental animals, can help predict that chemical's toxic effect on humans. The dose-response behavior is represented by a dose-response curve, which demonstrates that not all individuals will respond to a particular dose of a chemical in the same manner. Some people will be more sensitive than others, and a specific dosage that may be lethal to one person may not be lethal to another. The point on the curve where 50% of the test animals have died as a result of a particular chemical dosage is referred to as the Lethal Dose50, or LD50. The LD50 is usually indicated in terms of milligrams of substance ingested per kilogram of body weight (mg/kg). The lower the LD50, the more toxic the material. Inhalation of toxic substances can cause a great deal of tissue damage. Each lung is composed of a large surface area of folded tissue, which is vulnerable to assault by toxic vapors and airborne particles. The toxicity of a substance via inhalation is represented by TLVs,(Threshold Limit Values) or PELs (Permissible Exposure Limits). TLVs are compiled by the American Conference of Governmental Industrial Hygienists (ACGIH) based on available research, and are considered the industry standards. PELs are determined by the Occupational Safety and Health Administration (OSHA) and promulgated as enforceable standards. Both measures are expressed in parts per million (ppm) of the substance in air, or milligrams of substance per cubic meter of air. The exposure limits are identified as time-weighted averages (TWA) and the short-term exposure limits (STEL) or ceilings (C). The TWA of a substance is the average concentration to which an average worker can be exposed throughout an eight-hour work day without adverse effects. An important point to keep in mind is that the adverse effects of over-exposure to a material can range from headache or nausea to more severe disabilities. For this reason, time-weighted averages should be considered only as a guide in controlling health hazards in the laboratory, not as definitive marks between "safe" and "dangerous" concentrations. The STEL of a substance is the maximum amount to which an average worker can be exposed in a fifteen-minute period without adverse effects. Again, this is intended only as a rough guideline. The Ceiling limit of a substance is the concentration that should not be exceeded during any part of the work day. The toxicity of a substance via skin absorption can be determined several ways. Often, the threshold limit values of a substance will have a "skin" notation, indicating they are rapidly absorbed through the skin. Absorption can also be indicated by the solubility of the material in water. Materials that are extremely soluble in water can dissolve in skin moisture and be transported through the skin's surface. For instance, dimethyl sulfoxide (DMSO) rapidly absorbs into the skin. If any toxic materials are present in this solvent or on the surface of the skin, DMSO will transport these contaminants into the body as well. A substance can have either acute or chronic toxicity. A substance that is acutely toxic will have immediate effects on the health of an over-exposed individual, (e.g., phosgene causes immediate throat irritation at a concentration of 3 ppm and immediate death at 50 ppm). A substance that has chronic toxicity will eventually affect the health of a person due to long-term exposure to that material (e.g., phosgene in concentrations less than 1 ppm over a long period of time are a potential trigger for emphysema).
Poisons	A poisonous compound is a substance that causes death or serious injury if relatively small amounts are inhaled, ingested or have contacted the skin. All substances can be in some quantity or condition of use.
Labeling & Information	Any substance that carries the international poison symbol (skull and crossbones) should be treated as hazardous. Information on the poisonous nature of chemicals can be found in the MSDS section Health Hazard Data.
Storage & Handling	Treat poisonous compounds with extreme caution. Wear protective lab coats, gloves and safety glasses, and work in a functioning fume hood. For specific substance information call the Maryland Poison Control Center at 1-800-492-2414.

Special Classes of Materials

	Carcinogens are substances that will cause cancer in humans or animals given appropriate exposures. Suspect carcinogens are substances that have chemical similarities with known carcinogens or have shown preliminary evidence of carcinogenic activity. Carcinogens can represent an insidious hazard in the laboratory since they can cause disease with exposures that do not produce acute toxic effects. There may be a long latency period between exposure and the appearance of cancer. The consequence of exposure to carcinogens varies according to the species, the physiological and metabolic state of the organism, and the dosage of the carcinogen (including duration and route of exposure, concurrent exposure to other agents, and other factors). There is continuing scientific debate regarding the minimum exposure required to produce cancer, as well as the relevance of experimentally-induced animal cancers to a human situation. The complex interaction of such determinants makes risk assessment of human exposure to carcinogens exceedingly difficult. Due to these uncertainties, assurance of laboratory safety requires strict limitation of human exposure to carcinogenic substances. Some compounds are carcinogenic only in combination with certain other compounds. It is known that particular chemicals promote the carcinogenic action of others. Since the potential for synergistic action of most chemicals is unknown, it is essential that caution be exercised with all organic compounds and metals when used in combination with carcinogens.
Labeling & Information	The following terms, defined by the International Agency for Research on Cancer (IARC), are used to describe material carcinogenicity: Sufficient positive: Those chemicals that were found to promote and increase incidence of malignant tumors in multiple species or strains of lab animals. Limited positive: Those chemicals found to promote either malignant tumors in a single strain, or benign tumors in single or multiple species or strains. Inadequate: Insufficient evidence to make a decision. Equivocal: Almost no supporting evidence. Negative: Limited or sufficient significant negative evidence. Examples of known or suspected carcinogens are listed below. The risk factor associated with these compounds is high, and alternative compounds should be used whenever possible. 4-Nitrobiphenyl alpha- and beta- Naphthylamine * Methylchloromethyl ether 3,3'-Dichlorobenzidine * bis(chloromethyl) ether * Chloroform * Benzidine * 4-Aminodiphenyl Ethyleneimine * beta-Propiolactone Benzene * Dimethylaminoazobenzene Vinyl chloride * 1,2-dibromo-3-chloropropane * Arsenic * Acrylonitrile * N-Nitrosodimethylamine * Formaldehyde * * Designates a "Listed Hazardous Waste" (EPA). The Occupational Safety and Health Administration (OSHA) regulates the carcinogens listed below: 2-Acetylaminofluorene 4-Dimethylaminoazobenzene Acrylonitrile Ethylenimine 4-Aminodiphenyl Inorganic arsenic Asbestos 4,4'-Methylene bis(2-chloroaniline) Benzene Methyl chloromethyl ether bis-Chloromethyl ether beta-Naphthylamine Coke oven emissions 4-Nitrobiphenyl 1,2-dibromo-3-chloropropane n-Nitrosodimethylamine 3,3'-Dichlorobenzidine and its salts beta-Propiolactone Vinyl chloride alpha-Naphthylamine Benizidine Note: Anyone contemplating work with these carcinogens must contact the DES at (301) 405-3960 to make arrangements for initial environmental monitoring or engineering control evaluation. Depending on the results, laboratories may be required to meet the OSHA regulations on training, recordkeeping, personal monitoring and medical surveillance.
Access Control	Entrances into areas where known carcinogens are used should be posted appropriately, such as: "Cancer Suspect Agent, Authorized Personnel Only". Laboratory Supervisors/Principal Investigators are required to designate locations within the lab for use of carcinogens. The designation must include consideration of necessary control measures. Allow only authorized persons in the laboratory. Close all doors and restrict traffic in the work area when the carcinogen is being used. Place warning labels such as "Carcinogen" or "Cancer Suspect Agent" on all stock, dilution, and hazardous waste disposal containers. Visitors should be notified about carcinogen use in the laboratory work area. Housekeeping personnel must be informed of any possible hazards or special cleaning procedures that are required. All work with carcinogens should stop and the area and equipment decontaminated before Facilities Management personnel are permitted to repair or work on equipment, drains, or ventilation ducts.
Personnel Protection	In some high-risk operations involving carcinogens, a clean room or vestibule may need to be and shower constructed and properly used when entering and exiting a work area. Wear protective clothing, preferably disposable, such as gloves lab coats respirators when handling carcinogens. Do not wear them outside of the laboratory. Under normal working conditions, no carcinogen should contact gloves or clothing. They are the last line of defense. Check the manufacturer's description to be sure that the type of glove or respirator planned to be worn truly forms a barrier against the carcinogen being used. This is particularly true when using organic solvents, acids and bases. Use mechanical pipettes only. There should be no eating, drinking, smoking or other unnecessary hand-to-mouth contact. Only small amounts of carcinogens should be kept in stock. Only minimal amounts should be kept at work stations. Wash hands with soap after procedures involving a carcinogen.
Storage & Handling	Containers of carcinogens should be clearly labeled and kept in a separate (preferably locked) storage location. Designated work areas appropriate for carcinogen use should be clearly demarcated. Conduct work practices involving volatiles, aerosols or dust in a chemical fume hood exhausted to the exterior so that the possibility of entry into the supply air intake of any building is minimized. Check fume hoods, biological safety cabinets (laminar flow hoods) and glove boxes for leaks, air-flow rate and air-flow patterns prior to using them. Follow-up with periodic checks. All work surfaces on which carcinogens are used should be stainless steel or covered with plastic trays or dry absorbent plastic-backed paper. Laboratory supervisors are responsible for training laboratory workers on proper carcinogen-handling techniques. Each laboratory worker must adhere to proper operations, emergency procedures, monitoring of lab work and required medical examinations. Medical records must be accurately maintained when working with carcinogens. Before working with suspected or known carcinogenic compounds, obtain health hazard information for each compound. In addition, compile spill cleanup emergency procedures for your laboratory.
Mutagens and Teratogens
Mutagens	Mutagens are chemical and physical agents that induce mutations in DNA and in living cells. This affects the genetic system in such a way as to cause cancer or hereditary changes in chromosomes. Individuals exposed to chemicals with mutagenic properties may develop genetic damage to the extent that future offspring may be affected. Two forms of somatic (body/organ) cell interference may be noted. Leukemias: White blood cells are produced far more rapidly than they can be removed from the blood, interfering with normal body functions. Cancers: Cells that do not normally divide during adult life begin to proliferate to the extent that such division displaces or invades normal tissues. Examples of mutagens: Arsenic Ionizing Radiation (gamma, x-rays) Ethidium Bromide Alkylating agents (i.e.,dimethyl sulfate)
Teratogens	Teratogens are chemical and physical agents that interfere with normal embryonic development. Teratogens differ from mutagens in that there must be a developing fetus. Damage to the fetus (embryo) is most likely to occur early in pregnancy, during the first 8 - 10 weeks. Teratogens may produce congenital malformations or death of the fetus without inducing damage to the pregnant woman. In general, carcinogenic chemicals should be considered as a hazard to reproductive health. Even though OSHA has established exposure limits for dangerous materials, a developing fetus may be adversely affected by lower doses than those considered acceptable for adult exposure. Toxicology is still not well developed to evaluate reproductive health hazards. However, as of 1985, OSHA has identified three substances as teratogens: Dibromochloropropane Lead Ethylene oxide Examples of several other materials that are thought to be associated with reproductive health disorders are listed below. Antimony Carbon disulfide Ethylene thiourea Polychlorinated biphenols (PCBs) Nitrous oxide Formaldehyde Ethylene dibromide Ionizing radiation
Handling & Storage	See precautions as listed under carcinogens. Before working with suspected or known mutagenic or teratogenic compounds, obtain health hazard information for each compound. In addition, compile spill cleanup emergency procedures for your laboratory. Exercise extreme caution, as you would with carcinogens. Wear personal protective clothing and equipment, and work in a well ventilated area.
Biohazards & Infectious Waste
All laboratories involved in the use of human pathogenic microorganisms and recombinant DNA must be certified at a biosafety level established by the Biological Safety Officer. Contact the BSO at (301) 405-3960 for help with the certification process.
Biohazards	The laboratory supervisor is responsible for the safety of laboratory workers in their area. In handling biohazardous materials, the supervisor should consider: The biosafety level established for the lab by BACH. Current OSHA, EPA, and other pertinent requirements pertaining to biohazard use. This includes CDC-NIH guidelines as described in "Biosafety in Microbiological and Biomedical Laboratories." See Appendix IV for summary of biosafety level recommendations. Education/training provisions to introduce laboratory workers to biohazard use and disposal. Access to these areas should be limited to authorized personnel only. The concept of "universal precautions" must be observed when infectious materials or by-products are present. It is the responsibility of the laboratory supervisor to post the international biohazard symbol on all entrances to biohazard work areas along with pertinent emergency information. Individuals who have contact with human blood or blood products must comply with the "UM Bloodborne Pathogens Exposure Control Plan". Contact DES for more information at (301) 405-3960.
Biological, Pathological or Medical Waste	Transport and disposal of infectious waste must be done in accordance with guidelines as listed in the "UM Hazardous and Regulated Waste Management Manual", the UM Bloodborne Pathogen Standard and in the "UM Waste Disposal Guidelines" wall chart (the information provided is uniform in all 3 of these documents). Biological, Pathological or Medical Waste (BPMW) includes but is not limited to the following wastes: Cultures and stock of infectious agents and associated biologicals including culture from medical, pathological, research and teaching laboratories; wastes from the production of biologicals; discarded live and attenuated vaccines; and culture dishes and devices used to transfer, inoculate and mix cultures. Blood and blood products. Wastes consisting of human blood, human blood products (includes serum, plasma, etc.) and items contaminated by free-flowing human blood are BPMW. Pathological wastes. All pathological wastes and all wastes that are human tissues, organs, body parts, or body fluids that are removed during surgery, autopsy or other teaching or research procedures, and specimens of the above including their containers are BPMW. Sharps. Used or unused hypodermic needles, syringes, scalpel blades, pasteur pipettes, transfer pipettes, transfer pipette tips, scalpel blades, razor blades, blood vials, needles attached to tubing, needles used with sutures, culture dishes regardless of presence or absence of infectious materials, broken glass and similar devices likely to be contaminated with organisms that are pathogenic to healthy humans and all sharps used in patient care are BPMW. Animal wastes. All animal carcasses, body parts, potentially contaminated bedding, and related wastes are BPMW. (When animals are intentionally infected with organisms likely to be pathogenic to healthy humans for the purposes of research, in vivo testing, production of biological materials or any other reason; the animal carcasses, body parts, bedding material and all other potentially contaminated wastes must be treated as BPMW for storage and disposal.) Any residue or contaminated soil, water, or other debris resulting from the cleanup of a spill of any BPMW. Isolation wastes. Biological wastes and discarded materials contaminated with blood, excretions, exudates, or secretions of humans or animals who are isolated to protect others from highly communicable diseases, or isolated animals infected with highly communicable diseases. Any waste contaminated by or mixed with BPMW. All biological materials, including recombinant DNA, should be autoclaved prior to discarding.
Decontamination of Material	Materials known or suspected to be contaminated with an infectious agent must be sterilized by the generator. In general, autoclaving is the most effective and convenient form of sterilization.
Wet Heat (Steam)	Also known as autoclaving, this method requires a chamber temperature of at least 250oF(121oC). The processing time begins when the materials being sterilized reach the predetermined temperature. Monitor steam sterilization effectiveness with a biological indicator approved by the BSO. Post the "Autoclave Usage For Safety and Quality Control" sign available through DES near each autoclave in use.
Disinfectants	The following table lists a description of commonly used disinfectants:

Substance	Description
Alcohols	Ethyl or isopropyl alcohols at 70-80% concentration are good general purpose disinfectants; not effective against bacterial spores.
Quaternary Ammonium Compounds	Cationic detergents are strongly surface-active and extremely effective against lipoviruses; not effective against gram negative bacterial organisms and may be neutralized by anionic detergents (soaps).
Chlorine	Low concentrations (50-500 ppm) are effective against vegetative bacteria and most viruses; higher concentrations (2500 ppm) are required for bacterial spores; corrosive to metal surfaces; must be prepared fresh; laundry bleach (5.25% chlorine) may be used as a disinfectant.
Iodine	Recommended for general use; effective against vegetative bacteria and viruses; poor activity against bacterial spores. Betadine is a good disinfectant for washing hands.

Ethylene Oxide Gas (EtO)	Contact DES at (301) 405-3960 prior to using EtO for sterilization activities to assure compliance with OSHA regulation and BSO guidelines. . EtO gas is lethal for all known microorganisms, but is best used to sterilize heat-resistant organisms or heat-sensitive equipment. EtO sterilization is recommended only when an alternate sterilization method is not possible.
Disposal Procedures	For information on proper disposal procedures, see the "UM Hazardous and Regulated Waste Management Manual", the "UM Waste Disposal Guidelines" wall chart or call DES at (301) 405-3960.
Radioactive Materials and Radiation-Producing Equipment
	All researchers wishing to work with radioactive compounds must complete training and submit a fully completed application to the Radiation Safety Office (RSO), (301) 314-8336. There are federal and state regulations that are very strictly enforced, so be sure you are doing things correctly. All use of radioactive materials and radiation-producing equipment must be authorized by the Radiation Safety Officer. Individuals must be approved as Authorized users or work under the direct supervision of qualified personnel. Authorized Users are responsible for all safety aspects of radioactive materials handling. Periodic surveys of laboratories are conducted, and personal exposures are monitored for anyone working with radioactive materials. All requests for radiation measurements should be directed to the staff at (301) 314-8336. All purchasing, receiving and shipment of radioactive materials is done through the RSO of DES in room 2124 of the Chemical and Nuclear Engineering Building. For information on proper disposal procedures, see the "UM Hazardous and Regulated Waste Management Manual", the "UM Waste Disposal Guidelines" wall chart, the UM Radiation Safety Manual or call DES at (301) 405-3960. For more information concerning radiation safety requirements, call the RSO at (301) 314-8336.
Compressed Gases
	The purpose of this section is to assist the laboratory worker with identification, storage, maintenance and handling of compressed gases. Compressed gases can be hazardous because each cylinder contains large amounts of energy and may have high flammability and toxicity potential.
Labeling & Information	Compressed gas containers may be labeled in five ways: flammable gases are designated by a flame on a red label; non-flammable gas labels depict a gas canister on a green background poison gas labels depict a skull and crossbones oxygen-containing gases are designated by the letter "o" chlorine gas is distinctly labeled. Know the contents of the cylinder and be familiar with the properties of the gas. The contents of the cylinder or compressed gas should be clearly marked and identified with proper labels or tags on the shoulder of the cylinder. Those cylinders or compressed gases that do not comply with identification requirements should be returned to the manufacturer. If two labels are associated with one cylinder, affix the labels 180 degrees apart on the shoulder of each cylinder. Label all empty cylinders "EMPTY" or "MT" and date the tag. Treat an empty cylinder in the same manner that you would if it were full. All regulators, gauges, valves, manifolds, must be designed for the particular pressures and gases involved. They should bear the inspection seal of either Underwriters' Laboratories (UL®) or Factory Mutual Engineering Division of Associated Factory Mutual Fire Insurance Companies (FM®).
Storage & Handling	All cylinders should be stored in cool, dry, well-ventilated surroundings and away from all flammable substances including oil, greases, and gasoline. Do Not subject any part of a cylinder to a temperature higher than 125o F. Cylinders should not be located where objects may strike or fall on them. Cylinders should not be stored in damp areas, or near salt, corrosive chemicals, fumes, heat or direct sunlight. Store cylinders by gas type, separating oxidizing gases from flammable gases. Store flammable and oxidizing gases either 20 ft apart or separated by a 30 minute fire wall, five feet high. Keep a minimum number of cylinders on hand. All cylinders and compressed gases (full or empty) should be properly fastened and supported by straps, belts, buckles or chains to prevent them from falling and causing bodily harm or becoming a projectile. A maximum of two cylinders per restraint is preferred. Close valves and relieve pressure on cylinder regulators when cylinders are not in use. Valve handles must be in place when cylinders are in use. Do Not smoke in areas where there are flammable gases. Do Not extinguish a flame caused by a gas until the gas source has been shut off. A cylinder should only be moved while strapped to a wheel cart to ensure stability. When storing or moving cylinders, always attach safety caps. Do Not heat the cylinder or place a cylinder where it may become part of an electrical circuit. Compressed gases must be handled as high-energy sources and dangerous projectiles. All cylinders should be checked for damage prior to use. Do Not repair damaged cylinders yourself. Damaged or defective cylinders, valves, etc., must be taken out of use immediately and returned to the manufacturer for repair. Each regulator valve should be inspected annually. Never force valve or regulator connections. Threads and the configuration of valve outlets are different for each family of gases to prevent mixing of incompatible gases. When opening a cylinder, direct the cylinder opening away from personnel and open slowly. Do Not use lubrication on valve regulators. Do not refill a cylinder with a material other than that originally contained in the cylinder. Do not alter cylinder labeling. Do not alter the cylinder pressure by use of an external heat source. If an inert, flammable or toxic gas cylinder develops a small leak at the valve, carefully remove the cylinder to a hood or open space outdoors away from any possible source of ignition and all populations. Call DES for assistance.
Cryogenic Materials
	Cryogenic materials have special properties that make them particularly hazardous to use in the solid, liquid or gaseous states. They are characterized by severe low temperature (-60C to -270C). Cryogenic temperatures are achieved by liquefaction of gases, most commonly helium, hydrogen, nitrogen, argon, oxygen or methane.
Storage & Handling	The severely cold temperatures associated with cryogenic liquids (-60C to -270C) can damage living tissue on contact and embrittle structural materials. Liquefied under pressure, cryogenic liquids must be kept in specially designed, high-pressure vessels that contain fittings to relieve overpressure. When located in moist areas, ice formation can plug pressure release devices and pose an explosion hazard. For this reason, store vessels in a dry place and periodically check for ice formation. Cryogenic liquids present fire and explosion hazards. A flammable mixture, cooled in the presence of air with liquid nitrogen or liquid oxygen, can cause oxygen to condense and thereby present an explosion hazard. Keep away from ignition sources. Flammable liquids will support combustion in both the liquid and gaseous states. If allowed to depressurize, cryogenic liquids will rapidly and violently expand. Store and work with cryogenic liquids in a well-ventilated area to prevent the accumulation of flammable, toxic or inert gases as evaporation and condensation occurs near the cryogenic tank. Safety glasses and face shields should be used. For handling of cryogenic liquids, use potholders or appropriate thermal gloves. (Check with the glove manufacturer to assure the gloves will protect against the extreme temperatures of cryogenic material used.) Cushion glassware in a protective covering to prevent injury caused by flying glass in the event of implosion/explosion. Transport fragile cryogenic containers with caution -- use a hand truck if appropriate. Vent cryogenic storage containers outdoors or into a chemical fume hood system. Cryogenic gases Always pose a high pressure hazard since they are stored near boiling point. Liquid to gas evaporation causes high pressures to build up.
	Asbestos-Containing Materials
	Since the early 1900's, asbestos has been used extensively in the construction materials of buildings. Due to its low cost, fire and chemical resistance, insulation, and strengthening qualities, this "magic" mineral has been added to over 3,500 products found in the construction industry. The prolonged inhalation of asbestos fibers from these products has been linked to several lung diseases, including asbestosis, lung cancer and mesothelioma. Although the federal government banned the use of certain "friable" types of asbestos-containing materials (ACM) in 1978, many UM buildings were constructed and renovated prior to this time. Friable means that the material may be reduced to powder by hand pressure. Non-friable ACM will not be subjected to a total ban until 1997. For these reasons, nearly all UM buildings contain asbestos in some form. The key to living safely with ACM is proper management. DES has developed an asbestos management plan for all University buildings. This plan includes an operations and maintenance program, training in recognition, training for staff members who actually work with ACM, and a recordkeeping system for reporting and recording locations and conditions of these materials. Some types of building materials that commonly contain asbestos include sprayed-on fireproofing; acoustical plaster; pipe, tank and boiler insulation; lab bench tops; fume hood panels; ceiling and floor tile, and sheet floor covering. Provided asbestos materials are not disturbed in a manner which creates airborne dust, they cannot harm your health. If disturbance becomes necessary, such as during renovation projects or computer cable installation, only properly trained and protected personnel should perform these tasks. Should you encounter damaged suspect ACM in your work place, or if you may need to disturb or remove suspect materials, please contact DES for assistance at (301) 405-3960. Contact Personnel Services at (301) 405-5651 to sign up for a regularly scheduled asbestos awareness training class.

Labeling, Material Safety Data Sheets,
And Information and Training

	Labels should be the primary, initial source of warning for employees when handling hazardous chemical substances. Federal and State regulations mandate that all labels on original/stock containers of hazardous chemicals include the name of the hazardous chemical, appropriate hazard warnings, and the name and address of the manufacturer or other responsible party. Substances regulated by a specific OSHA standard must be labeled by the manufacturer according to the requirements of that standard. Example: OSHA 1910.1018(p) -- The Inorganic Arsenic Standard states that containers of inorganic arsenic must have a label which bears the following information: Danger Contains Inorganic Arsenic Cancer Hazard Harmful If Inhaled or Swallowed Use Only With Adequate Ventilation
Hazard Information	Hazard warnings found on the labels of hazardous chemical containers may be composed of pictures, symbols and words, or any combination thereof which convey the hazard(s) of the chemical. Picture hazard warnings help to identify the following properties and classes of hazardous compounds. explosives poisons oxidizers compressed gases flammables radiation corrosives biohazards Symbol hazard warnings provide basic information in determining what precautionary measures to use when handling hazardous chemical substances and/or dealing with a fire. The National Fire Protection Association (NFPA) uses a symbol system designed as a diamond-shaped label containing four differently colored squares: Blue Square ==> Health Hazard Red Square ==> Flammability Yellow Square ==> Reactivity White Square ==> "Special Hazards" A number (0 - 4) is added to each square indicating the order of hazard severity: 0 = No Special Hazards 4 = Severe Hazard Word hazard warnings contain a word or words intended to capture the worker's immediate attention (e.g., flammable, poison, fatal if swallowed). These word labels should be in English, but other languages may be used where needed. Signal words are warnings used to designate the degree of hazard. Danger ==> Highest degree of hazard (Red) Warning ==> Intermediate degree of hazard (Orange) Caution ==> Lowest degree of hazard (Yellow)
Label Use	Laboratory supervisors should ensure that all incoming containers of hazardous materials bear a label specifying: the name of the hazardous chemical. the appropriate hazard warning. the name and address of the manufacturer or other responsible party. Laboratory workers should not remove or deface labels on containers of hazardous chemicals. When chemicals are