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121.
The National Institutes of Health (NIH) is amending its regulations governing center grants to reflect their applicability to several new grant programs, including research on autism, Alzheimer's disease, fragile X disease, and minority health disparities and other types of health disparities.  相似文献   
122.
The Occupational Safety and Health Administration (OSHA) is amending the existing standard which limits occupational exposure to hexavalent chromium (Cr(VI)). OSHA has determined based upon the best evidence currently available that at the current permissible exposure limit (PEL) for Cr(VI), workers face a significant risk to material impairment of their health. The evidence in the record for this rulemaking indicates that workers exposed to Cr(VI) are at an increased risk of developing lung cancer. The record also indicates that occupational exposure to Cr(VI) may result in asthma, and damage to the nasal epithelia and skin. The final rule establishes an 8-hour time-weighted average (TWA) exposure limit of 5 micrograms of Cr(VI) per cubic meter of air (5 [mu]g/cu m). This is a considerable reduction from the previous PEL of 1 milligram per 10 cubic meters of air (1 mg/10 cu m, or 100 [mu]g/cu m) reported as CrO3, which is equivalent to a limit of 52 [mu]g/cu m as Cr(VI). The final rule also contains ancillary provisions for worker protection such as requirements for exposure determination, preferred exposure control methods, including a compliance alternative for a small sector for which the new PEL is infeasible, respiratory protection, protective clothing and equipment, hygiene areas and practices, medical surveillance, recordkeeping, and start-up dates that include four years for the implementation of engineering controls to meet the PEL. The final standard separately regulates general industry, construction, and shipyards in order to tailor requirements to the unique circumstances found in each of these sectors. The PEL established by this rule reduces the significant risk posed to workers by occupational exposure to Cr(VI) to the maximum extent that is technologically and economically feasible.  相似文献   
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