Planning and implementation of control practices for the prevention of occupationally acquired cancer and for the protection of the general environment is to be included in all research programs and staff jobs involving known or suspected chemical carcinogens.
Definition
Chemical carcinogens are chemicals, which have been demonstrated to cause a malignant disease or an increased incidence of cancer, by the appearance of tumors at an earlier time than would be otherwise expected, or by promotion of tumors initiated from exposure to other chemicals.
OSHA currently regulates twenty-three chemical carcinogens, twenty-one of which may exist at WCU. However, the OSHA Research Division has listed in THE REGISTRY OF TOXIC EFFECTS OF CHEMICAL SUBSTANCES more than 2000 substances for which there is allegedly some degree of evidence of tumorigenicity or carcinogenicity, some of which will be subject to future regulation.
Some potential carcinogens found in research laboratories will not be included in these lists, because they are not ordinarily found in the industrial workplace and because there may not have been sufficient carcinogenicity testing. The faculty member is responsible for knowing the available information relating to the hazard potential for the chemicals used in his/her laboratory and should exercise judgment, in consultation with the Safety Officer as to the appropriate safety precautions which should be followed.
Facility Requirements
A designated work area must be established, access for which is restricted to personnel who are aware of the hazards of the substances in use and the precautions which are necessary. A foot or elbow operated hand wash facility should be available within the work area. A shower facility, should be also located in the building.
The designated area may be the entire laboratory or a device such as a laboratory hood.
The exhaust ventilation system should maintain an inflow of air from the unregulated
area into the work area. The exhaust air from the work area must be discharged directly
to the outdoors clear of occupied buildings and air intakes. No re-circulation of
exhaust air from the work area is permitted. The exhaust air from glove boxes should
be treated by HEPA and charcoal filtration. The need for and type of treatment for
other primary containment equipment should be determined by the Health and Safety
Office. Exhaust air
treatment systems that remove chemical carcinogens from the exhaust air by collection
mechanism such as filtration or absorption should be operated in a manner that permits
maintenance so as to avoid direct contact with the collection medium. All exhaust
air from primary containment equipment must be discharged directly to the outdoors
so that it is dispersed clear of occupied buildings and air intakes.
Protective Clothing
Protective clothing such as a full-fastened laboratory coat or a disposable jumpsuit is to be worn in any area in which chemical carcinogens are being used. Clean clothing is to be provided weekly and should not be worn outside of the work area. Clothing contaminated by chemical carcinogens is to be decontaminated or disposed of immediately after an obvious exposure. Contaminated clothing must not be sent to the laundry until decontaminated. Gloves must be worn when handling chemical carcinogens. The practice of double gloving when handling chemical carcinogens is recommended. Disposable gloves are to be discarded after each use and immediately after known contact with a chemical carcinogen.
Work Area Identification
Entrances to all work areas, where chemical carcinogens are being used or stored, must be posted with signs bearing the legend: CAUTION - CHEMICAL CARCINOGEN Authorized Personnel Only.
Use of Primary Containment Equipment
Procedures involving volatile chemical carcinogens and those involving solid or liquid chemical carcinogens that may result in the generation of aerosols must be conducted in a chemical fume hood, a biological safety cabinet, a glove box, or other suitable containment equipment. Examples of aerosol producing procedures are: the opening of closed vessels; transfer operations; weighing preparation of feed mixtures; and the application, injection, or incubation of a chemical carcinogen into experimental animals. Class II, type B biological safety cabinets are suitable for the conduct of tissue culture and other biological procedures involving chemical carcinogens. The faculty member should obtain guidance from the Health and Safety Office on the selection and use of Class II biological safety cabinets. Primary containment equipment used for chemical carcinogens must display a label bearing the legend: CAUTION CHEMICAL CARCINOGEN.
Use of Analytical Instrumentation
Analytical instruments, when used with chemical carcinogens, are to be placed entirely within a chemical fume hood. When this is impossible, vapors or aerosols produced by these instruments should be captured through local exhaust ventilation at the site of their production. When a sample is removed from the analytical instrument, it should be placed in a tightly stoppered sample tube or otherwise safeguarded from contaminating the laboratory. Analytical equipment that becomes contaminated should not be used until it has been completely decontaminated.
Storage, Inventory and Identification
Stock quantities of chemical carcinogens are to be stored in designated storage areas. The storage areas should be posed with signs bearing the legend: CAUTION - CHEMICAL CARCINOGEN Authorized Personnel Only. An inventory of stock quantities is to be maintained by the faculty member, who should provide copies to the Health and Safety Office. The inventory records should include the quantities of chemical carcinogens acquired and dates of acquisition and disposition. Storage vessels containing stock quantities should be labeled: CAUTION - CHEMICAL CARCINOGEN.
Working Quantities
Quantities of chemical carcinogens present in the work area should be kept to a minimum. Quantities should not normally exceed the amounts required for use in one week. Storage vessels containing working quantities should be labeled: CAUTION - CHEMICAL CARCINOGENS.
Laboratory Transport
Storage vessels containing chemical carcinogens are to be first placed in an unbreakable outer container before being transported to laboratory work areas. Contaminated materials, which are transferred from work areas to disposal areas, must first be placed in a closed plastic bag or other suitable impermeable and sealed primary container. The primary container must be placed in a durable outer container before being transported. The outer container is to be labeled with both the name of the chemical carcinogen and the warning: CAUTION - CHEMICAL CARCINOGEN.
Protection of Vacuum Lines
Each vacuum service, including water aspirators, is to be protected with an absorbent or liquid trap and a HEPA filter to prevent entry of any chemical carcinogen into the system. When using a volatile carcinogen, a separate vacuum pump or other device placed in an appropriate chemical fume hood should be used.
Packaging and Shipping
Chemical carcinogens are to be packaged to withstand shocks pressure changes, and any other condition, which might cause leakage of contents incident to ordinary handling during transportation. Shipments are to be in accordance with DOT regulations.
Decontamination
Contaminated materials must either be decontaminated by procedures that decompose the chemical carcinogen, or be removed for subsequent disposal. Chemical carcinogens, which have spilled out of a primary container so as to constitute a hazard, must be inactivated in situ or should be absorbed by appropriate means for subsequent disposal. A means for assuring adequacy of clean up should be provided, for instance wipe tests or fluorescence tests.
Disposal
Plans for handling and ultimate disposal of contaminated wastes are to be approved by the Health and Safety Office.
Animal Experimentation
Animal care personnel are to wear a completely closed jumpsuit or a complete clothing change and laboratory issue shoes or booties, head cover, and gloves. Clean clothing should be provided daily. Animal care personnel engaged in procedures where exposure to airborne particles contaminated with chemical carcinogens could occur must wear an appropriate facemask or respirator.
The selection and use of an appropriate face mask or respirator is to be approved by the Health and Safety Office. The facemask or respirator is not to be worn outside of the animal room. Used filters should be disposed of and the respirator housing should be decontaminated daily. Personnel should shower after completion of procedures that may result in the creation of airborne contamination in the animal room.
Experimental animals are to be housed in cage systems that confine feed, feces, urine, and bedding within the enclosure. When using a volatile chemical carcinogen, the cage must be used in conjunction with appropriate ventilation systems. Alternative animal housing methods must be approved by the Health and Safety Office.
Medical Consultation
Medical examinations are to be completed for employees who develop signs or symptoms associated with a hazardous chemical or whenever there is reason to believe that the employee has been exposed to a substance above OSHA limits.
OSHA Regulated Carcinogens:
Asbestos See Policy #26 (WCU Safety Manual)
4 Nitrobiphenyl
Alpha Naphthyllamine
Methyl chlorometehyl ether
3,3' Dichlorobenzidine (and its salts)
Bis Chloromethyl ether
Beta Naphthylamine
Benzidine
4 Aminodiphenyl
Benzene
Ethyleneimine
Beta Propiolactone
2 Acetylaminofluorene
4 Dimethylaminoazobenzene
N Nitrosodimethylamine
Vinyl chloride
Inorganic arsenic
1,2 dibromo 3 chloropropane
Acrylonitrile
Ethylene Oxide
4,4 Methylene dianiline
Formaldehyde
1,3-Butadrene
Methylene Chloride
Flammables
General
It is the policy of the University to use the recommendations contained in the National Fire Protection Association (NFPA) Codes as minimum guidelines to acceptable practices on Campus. A number of the NFPA Codes have been incorporated into the Occupational Safety and Health Act (OSHA) Standards, the North Carolina State Fire Prevention Code, or are mandated as a condition of insurance coverage by the North Carolina Department of Insurance. Questions regarding the applicability of specific NFPA Codes should be directed to the University Safety Officer.
The purpose of this policy statement is to list the basic standards for the storage and use of flammable and combustible liquids applicable to Campus operations. The standards listed here are by no means comprehensive but represent those cited most frequently during inspections of Campus facilities.
Definitions
Laboratory/Shop Unit:
A laboratory or shop unit is defined as a room, or suite of rooms, separated from adjacent areas by fire resistant walls and doors.
Flash Point
The minimum temperature at which a liquid gives off vapor in sufficient concentration to form an ignitable mixture in air.
Flammable Liquids:
A flammable liquid is any liquid having a flash point below 100oF (37.8oC). Flammable liquids are also known as Class I liquids and subdivided according to flash point and boiling point as indicated in the Table below.
Combustible Liquids:
A combustible liquid is any liquid having a flash point at or above 100oF, and is known as a Class II or III liquid as indicated in the following Table:
Classes:
Flammables Combustibles
lA IB IC II III
Flash point <73o <73o 73o 100o 100o 140o >140o
Boiling Point <100o >100o
Maximum Container Size for Point of Use Storage
The potential fire hazard depends on the flash point and the quantity of liquid being used. The following table gives the maximum size container allowed for each class of liquid:
Container
Type IA IB IC II III
Glass or Plastic 1 gal 1 gal. 1 gal. 1 gal. 1 gal.
Metal 1 gal. 5 gal. 5 gal. 5 gal. 5 gal.
Safety Cans 2 gal. 5 gal. 5 gal. 5 gal. 5 gal.
Maximum Quantities
The potential fire hazard also depends on the total quantity of flammable and combustible liquids present within a containment unit and the type of containers in which the liquids are stored. The maximum quantity allowed per unit is as follows:
l) Shelf or open storage/use:
a) Glass, plastic, or cans 10 gallons
b) Safety cans 25 gallons
2) Approved storage cabinets:
a) Class I & II 60 gallons
b) Class III(maximum 2 per unit 120 gallons
3) Inside Storage Room (meeting NFPA Code recommendations)
a) with sprinkler 4 10 gal/ft2
b) without sprinkler 2 4 gal/ft2
University Guidelines
It should be emphasized that the quantity of flammables on hand must be kept to a minimum and that only in unusual circumstances will the maximum quantities be permitted. The following guidelines have been adopted by the University:
- If a one gallon quantity of one specific liquid represents more than a thirty day supply of a Class IA or IB flammable, one-pint (IA) or one-quart (IB) shall be used.
- Multiple cans and/or bottles of any one specific flammable will not be permitted in open storage or storage cabinet if it represents more than a thirty day supply of that flammable.
- Deviations from these guidelines may be granted in exceptional cases following approval by the University Safety Officer.
Gasoline must be stored and transported on campus in safety cans. The use of safety cans in laboratories is encouraged where practicable.
Class I liquids shall not be transferred between metal containers unless the containers are electrically interconnected by direct bonding or by indirect bonding through a common ground. The maximum impedance of the bond shall not exceed 6 ohms.
Storage Cabinets
Storage cabinets constructed to NFPA standards should be used when required to meet quantity limits. Storage cabinets are not permitted in hallways.
Inside Storage Rooms
A central storage room is preferable to storage cabinets in each laboratory. This central storage alternative should be considered especially by departments and schools which have centralized supply rooms.
Refrigerators
Flammable liquids must not be stored in domestic type refrigerators. Domestic type refrigerators should not be purchased for laboratory use, even if flammable storage is not contemplated, since future research needs may require the use of flammables. Safety refrigerators, which have the electrical contacts (door switch, light, thermostat, etc.) removed or exteriorized, are recommended for laboratory use. "Explosion Proof" refrigerators are not recommended except in unusual circumstances, such as in an inside storage room (for flammables) or in potentially hazardous atmospheres. Domestic type refrigerators currently in laboratories should be labeled "DANGER/UNSAFE FOR STORAGE OF FLAMMABLES".
Warning Signs
Bunsen burners and other open flames must not be used in the area where flammable liquids are being used. The area must be posted "NO SMOKING" and containers are to be labeled "DANGER FLAMMABLE KEEP AWAY FROM HEAT, SPARKS, AND OPEN FLAMES, KEEP CLOSED WHEN NOT IN USE."
Variances/Specialized Needs
Variations from these guidelines may be granted when chemical purity other considerations warrant. For further information, contact the University Safety Officer (7443).
Radiation Safety
General
To obtain authorization to possess radioactive materials or radiation producing machines faculty members must send an application form to the North Carolina Radiation Protection Division, Department of Environment Health and Natural Resources, P. O. Box 27687, Raleigh, North Carolina 27611, phone number (919) 733-4283. The Radiation Protection Division should be contacted directly to obtain the necessary forms and application procedure.
Individual License
A specific license will be issued for each application. The faculty member making the application will be the person responsible for the safety and disposal of the material and will be designated Radiation Protection Officer for the material or equipment.
Inspections
Inspections for compliance with the terms of the license will be periodically conducted by the Radiation Protection Division.
Safety & Risk Management
The Safety Office, (7443) will provide administrative support in obtaining regulated material or equipment and in maintaining compliance with Radiation Protection Standards. A copy of each license application and approved license should be forwarded to the Safety & Risk Management Office.
Lasers
Laser equipment is not required to be licensed by the Radiation Protection Division. However, room isolation shielding and warning signs are required to prevent accidental exposure to the eye and skin. Faculty members working with the laser equipment should contact the Safety Officer and formulate an individual Safety plan to control exposures to laser energy.
The hazards created by lasers are categorized into four main groups:
Class I: Exempt laser devices cannot create eye damage if viewed accidentally. This class has less than 0.001 milliwatt power.
Class II: Low power lasers have fewer than 1 milliwatt outputs and, under certain conditions, can require eye protection.
Class III: Medium power lasers have fewer than 0.5 watts of power and can exceed the eye injury level. Protection may be required.
Class IV: High power lasers have greater than 0.5 watts of power and eye protection is required.
Compressed Gases
Standards
The use of compressed gases on campus will be in accordance with recommendations published by the Compressed Gas Association.
The following rules summarize a few of the basic guidelines for the use and storage of compressed gases:
Support Required
Compressed gas cylinders must be supported at all times, whether full or empty. Acceptable methods of support include:
Wall mounted or bench mounted gas cylinder brackets.
Chains or belts anchored to walls or benches.
Free standing dollies or carts designed for gas cylinders and equipped with safety chains or belts.
Valve Protection Cover
A cylinder must have the valve protection cover in place except when in use.
The pressure regulator must be removed and valve protection cover replaced before moving cylinders even if the cylinders are secured to a dolly or hand truck, e.g., acetylene and oxygen cylinders used for cutting, brazing, etc., may not be transported with regulators attached to the cylinders.
Flammable Gases
Smoking is not permitted in the area where flammable gases are used or stored.
Flammable gas cylinders (acetylene, propane, hydrogen, etc.) must be stored separately from oxidizers (oxygen, chlorine, etc.).
Upright
Gas cylinders must be used in an upright position and clamped securely at all times. Due to the extreme hazards created by using certain cylinders in a horizontal position (e.g., acetylene liquid gases), approval must be obtained from the Health and Safety Office for use of cylinders in any position other than vertical, with the valve up.
Movement of Cylinders
Appropriate dollies or hand trucks must be used to move cylinders weighing more than 50 pounds. Movement by spinning, sliding, rolling, etc., is prohibited. For movement within shops and laboratories, cylinders weighing less than 50 pounds may be carried if desired.
Toxic and Poisonous Gases
Toxic and poisonous gases must be used only in fume hoods or other enclosures vented directly outdoors. Appropriate warning signs and information must be provided and clearly marked at room entrances.
Piping systems for flammable gases, toxic gases, and oxygen must be approved by the Health and Safety Office.
Pressure regulators and gauges must be compatible with the cylinder valves, i.e., the use of adapters is prohibited.
Oxygen
All oxygen valves, gauges, regulators, pipes and fittings must be scrupulously free of oil, grease, graphite, or any other oxidizable substance. Such pipes, gauges, fittings, etc., must at no time be exposed to come to an elevated temperature due to proximity to welding operations, burners, or other heat sources. Although oxygen is quite safe under normal temperatures and pressures, elevated temperatures and/or pressures, or contamination, may result in the rapid and violent oxidation of normally non reactive materials. For example, a regulator used on oil pumped nitrogen could produce a serious explosion if subsequently used for oxygen, due to the oil residue.
Organic Peroxides
Safe Handling of Peroxidizable Compounds
Peroxide formation in solvents and reagents has caused many accidents. Every worker must learn to recognize and safely handle peroxidizable compounds. Peroxides form by the reaction of a peroxidizable compound with molecular oxygen through a process call autoxidation or peroxidation. Peroxidizable compounds are insidious. Under normal storage conditions they can form and accumulate peroxides, which may explode violently when subject to thermal or mechanical shock.
Peroxides in solution at concentrations up to about 1 percent do not normally present thermal or shock hazards. Such solutions may be safely disposed of or treated to remove peroxides. However, should crystals form in a peroxidizable liquid or discoloration occur in a peroxidizable solid, peroxidation may have occurred, and the product should be considered extremely dangerous and disposed of without opening the container.
Storage
Quantities of peroxidizable compounds should be purchased according to short term needs. For instance, buy six (6) one pound cans of ether instead of the six pound can. Purchasing of package sizes corresponding to use requirements will also minimize exposure to air from multiple openings of the container. A tight cap on a nearly full bottle probably provides almost total protection against peroxide formation.
Peroxide accumulation can be held to very low levels by storage in reasonably full containers (25% maximum headspace) with TIGHT caps that are replaced promptly after use. Still more protection can be provided by inserting the headspace over peroxidizable cups by nitrogen flushing before reclosing the container.
Vinyl monomers containing certain inhibitors are exceptions to inserting. The use of oxidation inhibitors is especially important in the safe handling of peroxidizable materials. Hydroquinone, alkyl phenols, aromatic amines, or similar materials are recommended by the manufacturers as being effective in preventing peroxide formation during storage of peroxidizable compounds. These inhibitor selected should be compatible with use or purity requirements of the compounds. A program of periodic testing and replenishing inhibitor levels should be followed during storage of peroxidizable materials.
Each laboratory, as part of their Chemical Hygiene Plan, should maintain an inventory of peroxidizable compounds. This listing should be reviewed every semester and either test or discard those out of date.
In addition, each container of peroxide forming chemicals should have the following dates written on the label.
- Date Received
- Date Opened
- Date to be Discarded
In some cases, where peroxides are chemically removed, then a notation on the label would indicate the new date.
Peroxide forming chemicals should be stored together in full, airtight opaque containers at temperatures below 30oC and in the dark. Use only refrigerators designated for flammable liquids.
Removal of Peroxides
Peroxide impurities in water insoluble solvents (ether, hydrocarbons) are easily purified by shaking with the following solution:
- 60 gr of ferrous sulfate
- 6 ml of concentrated sulfuric acid
• 110 ml of distilled water
Water is introduced by this method so post drying will be required if a dry solvent is wanted.
Disposal
Immediately set aside and DO NOT USE any peroxide forming chemicals that have formed crystals, precipitates, solids or an oily viscous layer, or any rusted, damaged, undated or suspicious containers of peroxide forming chemicals.
Never attempt to force open a rusted or stock cap or a cap encrusted with scale on a container of peroxide forming chemicals. Never attempt to clean by scraping or rubbing glassware or other containers if an oily deposit or crusty residue is present.
Empty containers of ethers and other peroxide formers are to be flushed with water before discarding.
Distillation and Evaporation Precautions
Testing peroxidizable solvents for peroxides prior to distillation or evaporation should be routine. One common cardinal sin is the carrying out of a distillation too close to dryness allow at least a 10% heel for safety sake. Never distill to a dry residue.
Safety Plan (See Section 1, #7)
The safety plan should include a review of possible hazards from the use of peroxidizable chemicals in the experiment. The safety plan should include the following factors:
- The starting chemicals
- The experimental procedure
- The end products
If the plan indicates that peroxide may be present, then described procedures for handling, testing and removal should be followed.
- SPECIFIC PEROXIDIZABLE COMPOUNDS -
Some of the specific compounds that form peroxides during storage are included in list A, B, & C. Those that form peroxides that may explode even without being concentrated are in List A. List B. includes chemicals that are dangerous when concentrated by distillation of evaporation. List C is vinyl monomers that can form peroxides that may initiated explosive polymerization of the monomers.
TABLE II
COMMON COMPOUNDS THAT FORM PEROXIDES DURING STORAGE
|
List A - Red Label (Three Months) Peroxide Hazard on Storage |
List B - Yellow Label (Twelve Months) Peroxide Hazard on Concentration |
List C - Yellow Label (Twelve Months) Hazard Due to Peroxide Initlation of Polymerization |
|
Isopropyl Divinyl acetylene vinylidene chloride Potassium metal Sodium amide |
Ethyl ether Tetrahydrofuran Dioxin Acetyl Methyl I-butyl keton Ethylene glycol dimethyl ether (glyme) Vinyl ethers Dicyclopentadiene Diacetylene Methyl acetylene Cumene Tetrahydronaphthalene Cyclohexene Methylcyclopentane t-Butyl alcohol |
Styrene Butadiene Tetrafluroroethylene Chlorotrifluoroethylene Vinyl acetylene Vinyl acetate Vinyl pyridine Chlorobutadiene (Chloroprene) 9,10 Dihydroathracene Indene Dibenzocyclopentadiene
|
*When stored as a liquid, the peroxide-forming potential increases and certain of these monomers (especially butadiene, chloroprene, and tetrafluoroethylene) should then be considered as list A compounds.
Peroxide accumulation is a balance between the rate of peroxide formation and the rate of peroxide degradation for the particular substance under the environment of the sample. For example, certain highly reactive compounds, such as organometallic, accumulated peroxide at low temperatures because the peroxide degradation rate is slowed relative to the formation rate. In contrast, less reactive compounds, such as hydrocarbons or ethers, are usually best kept at low temperatures.
The more volatile the peroxidizable compound, the easier it is to concentrate the peroxides. One should also remember that pure compounds are more subject to peroxide accumulation because impurities may inhibit peroxide formation or catalyze their slow decomposition.