OSHA's new Respiratory Protection Standard requires employers to fully comply with its provisions by October 5, 1998 though a 90 day enforcement extension has been granted since the Standard's issuance. 2. The Standard specifies many new minimum requirements for protecting the health and safety of respirator users. A critical determinant of excellence in respiratory protection will be the thoroughness with which the mandated written program addresses essential worksite applications. 3. Highlights of the Standard include a mandatory medical questionnaire (or equivalent examination) for all (voluntary and nonvoluntary) respirator users (with the exception of voluntary filtering facepiece users), expanded respirator fit testing protocols, information/training provisions, and program evaluation requirements.