Contains corrections to the preamble to the final rule on Hazardous Waste Operations and Emergency Response and to the final standard, 29 CFR 1910.120 as amended effective 3/6/90, published in the Federal Register on 3/6/89 (54 FR 9294). Corrects typographical errors, incorrect citations, and makes clearer certain areas in both the standard and the preamble. Corrections include a definition of "hazardous substance"; clarification of OSHA''s intent that medical surveillance be provided to employees who develop signs or symptoms due to possible over exposure from hazardous substances whether the employee is engaged in hazardous waste operations or emergency response; clarifies the exception paragraph of paragraph (a)(2)(iii) and the introductory language of paragraph (p); and correction of the term "workplace" to "danger area" in provisions covering emergency response evacuation. Effective date: April 13, 1990. Contact: James Foster, 523- 8148.