OSHA reduced exposure limits for 375 air contaminants on 1/19/89 at 54 FR 2332. The new exposure limit for nitroglycerin (NG) of 0.1 mg/m(3) measured as a 15-minute Short Term Exposure Limit (STEL) was stayed for the manufacture of NG and NG-based explosives and propellants for military and space use. The Transitional (prior) limit of a ceiling of 2 mg/m(3) has remained in effect. OSHA is partially extending the stay so that compliance with the new exposure limit by use of any reasonable means including respiratory protection is to be phased in between November 1, 1990 and March 1, 1992, and the requirement for compliance using engineering controls is to be phased in between December 31, 1992 and December 31, 1998. Effective 11/1/90. CONTACT: James Foster (202) 523-8151.