The policy establishes the criteria and procedures OSHA will use to decide which substances should be regulated as potential occupational carcinogens. It requires specifying clear criteria because determining carcinogenicity is scientifically complex, and sets out that substances posing potential cancer risks to workers will be identified using those criteria (1990.111(a)).
Decisions are made based on an extensive review of scientific data and expert opinions and will be consistent with the part's policies and procedures; the criteria can be amended as new science develops. OSHA will base determinations on scientific evaluation of the evidence for each substance (1990.111(b)).
This part applies to individual substances, groups of substances, and combinations or mixtures that may be found in U.S. workplaces. For each rulemaking, OSHA will specify which exact substances or mixtures are covered and will review whether the available evidence appropriately applies to that range (1990.111(c)).
OSHA will identify potential occupational carcinogens using human epidemiological studies and/or experimental carcinogenesis bioassays in mammals, and it will use positive results in short-term tests as supporting (concordant) evidence. These lines of evidence form the basis for classification (1990.111(d)).
No — positive short-term tests are treated as concordant (supporting) evidence, not as the sole basis for classification; OSHA relies primarily on human studies and mammalian bioassays, using short-term tests to support those findings (1990.111(d)).
OSHA will classify and regulate potential occupational carcinogens in accordance with the policy and will consider the scientific evidence about each substance during individual rulemakings; the issues reviewed in those rulemakings will be limited as specified in the policy (1990.111(e)).
OSHA classifies potential occupational carcinogens into two categories based on the nature and extent of available scientific evidence, and those two categories may be regulated differently depending on the strength and type of evidence (1990.111(f)).
The policy requires that OSHA establish a procedure for setting priorities for evaluating and regulating potential carcinogens and that those priorities be made public. This ensures transparency about which substances will be addressed and when (1990.111(g)).
Worker exposure to Category I potential carcinogens must be reduced primarily through engineering controls and work practice controls. OSHA emphasizes these controls as the main methods to lower exposure levels (1990.111(h)).
Exposure to Category II potential carcinogens will be reduced as appropriate on a case-by-case basis during individual substance rulemakings, consistent with statutory requirements; if OSHA sets a permissible exposure level (PEL) for a Category II substance, it must be met primarily through engineering and work practice controls (1990.111(i)).
OSHA must base cancer risk assessments on the available data and, because of uncertainties and the serious consequences of understating risk, it must use cautious and prudent assumptions when estimating risk to workers (1990.111(j)).
If the Secretary determines that suitable substitutes exist for certain uses of a Category I potential carcinogen that are less hazardous, OSHA will set a no occupational exposure level for those specific uses, and that level must be achieved solely through engineering and work practice controls to encourage substitution (1990.111(k)).
OSHA decides the specific identity and the range of substances and mixtures to be covered in each individual rulemaking, and will review whether the scientific evidence appropriately applies to the proposed range (1990.111(c)).
Engineering and work practice controls are the primary methods OSHA requires to reduce worker exposure to both Category I and Category II potential carcinogens; Category I exposures should be reduced primarily through those controls and any PELs for Category II must also be met primarily by them (1990.111(h), 1990.111(i)).