4.4 Special Procedures for "Inimical" Chemicals (defined in Section 5.3.1)
OSHA has noted that many laboratory workers use known or suspected carcinogens, reproductive toxins, and substances with a high degree of acute toxicity. While industrial workers might use only one or a limited few such chemicals, laboratory workers are likely to use many. In addition laboratory workers are more likely to use chemicals of unknown toxicity.
Exposures to such chemicals, referred to hereafter as "inimical chemicals," may have an additive or synergistic impact on risk. To limit the possible exposures, the College has special procedures and precautions for work with inimical chemicals. (See Appendix A for an illustrative list of such inimical chemicals used at the College, and subject to this section.)
Special work areas shall be designated for work with inimical chemicals. The rooms containing these areas, including storage areas for these chemicals, shall have restricted access. All entrances to a laboratory where inimical chemicals are used or stored shall be posted with permanent signs indicating the use of specific classes of chemicals (e.g., carcinogens, mutagens, etc.) and stating "Authorized Personnel Only." If necessary, the rooms will be locked. Only personnel with special instruction on the hazards and safe handling of inimical chemicals shall be permitted access to the areas. All such areas shall be registered with the Department of Public Safety.
Rooms containing areas where inimical chemicals are used and stored will be kept at a slight negative pressure when compared to adjacent rooms and hallways to ensure air flow from uncontaminated to contaminated areas.
All work involving inimical chemicals shall be done in specially equipped closed systems to reduce the risks of laboratory worker exposure to the vapors. The closed systems may include fume hoods, glove boxes, or similar devices. These systems must be equipped with HEPA filters and an adsorbent to decontaminate air exhausted from them before release to the environment. If glove bags are used these should be confined to a fume hood, and verified decontamination procedures used, to insure protection of the worker.
Rinse water and other waste streams contaminated with inimical chemicals shall be collected for disposal. Specific disposal procedures, consistent with the Resource Conservation and Recovery Act, will be outlined by the College's Safety Coordinator.
Laboratory workers using inimical chemicals shall take extra care to maintain good personal hygiene. In addition to the hygiene practices in Section 4.1.2, workers will thoroughly wash their hands, forearm, face and neck immediately after working with the inimical chemical. Persons working in designated areas should not wear any personal items such as jewelry which might be lost if decontamination is not possible.
To protect vacuum lines and pumps, HEPA filters or high efficiency scrubber systems should be used upstream of any other protective devices such as low-temperature traps. Exhausts should be vented into a fume hood. Motor-driven vacuum pumps are recommended because they are easy to decontaminate. Decontamination should be carried out in an exhaust hood. Pump oil should be changed monthly, and the waste oil treated as hazardous waste.
Whenever possible disposable apparel should be used and incinerated after use. Gloves and long sleeves should be used at all times to prevent skin contact with the inimical chemical.
Inimical chemicals should be stored only in a ventilated, limited access area in appropriately labeled, unbreakable, chemically resistant secondary containers.
Contingency plans, equipment, and materials to minimize exposures of people and property in case of spills or accidents shall be readily available.
Work with inimical chemicals should be done with the smallest amounts possible. Purchases of the chemicals should be restricted to the minimum amounts necessary to prevent uninterrupted work.