Skip directly to search Skip directly to A to Z list Skip directly to page options Skip directly to site content


This online archive of the CDC Prevention Guidelines Database is being maintained for historical purposes, and has had no new entries since October 1998. To find more recent guidelines, please visit the following:

NIOSH Recommendations for Occupational Safety and Health Standards 1988

MMWR 37(S-7);1-29

Publication date: 08/26/1988

Table of Contents



Definitions of Abbreviations and Terms




Acting under the authority of the Occupational Safety and Health Act of 1970 (Public Law 91-596), the National Institute for Occupational Safety and Health (NIOSH) develops and periodically revises recommendations for limits of exposure to potentially hazardous substances or conditions in the workplace. NIOSH also recommends preventive measures designed to reduce or eliminate the adverse health effects of these hazards. In formulating these recommendations, NIOSH evaluates all known and available scientific information relevant to the potential hazard. The recommendations are then published and transmitted to the Occupational Safety and Health Administration (OSHA) or the Mine Safety and Health Administration (MSHA) of the U.S. Department of Labor for use in promulgating legal standards.

NIOSH recommendations are published in a variety of documents. Criteria documents specify a NIOSH recommended exposure limit (REL) and appropriate preventive measures designed to reduce or eliminate adverse health effects.

Special hazard reviews, occupational hazard assessments, alerts, and technical guidelines are other types of NIOSH documents that complement the Institute's recommendations for standards. These documents provide safety and health assessments of specific problems associated with a given agent or hazard, and they recommend appropriate control and monitoring methods. Although these documents do not supplant the more comprehensive criteria documents, they are prepared to assist OSHA or MSHA in the formulation of regulations.

NIOSH periodically presents testimony before various Congressional committees and at regulatory hearings convened by OSHA or MSHA. The testimony always includes the current NIOSH policy concerning the hazard in question.

NIOSH Current Intelligence Bulletins (CIBs) review and evaluate new and emerging information on occupational hazards. These bulletins may draw attention to a formerly unrecognized hazard, report new data on a known hazard, or disseminate information on hazard control.

The recommendations listed in this summary are based on existing NIOSH policy as previously published in any of the forms listed above. The intent of this table is to provide a rapid reference to the most recent NIOSH REL or other recommendation for each potential hazard. The current OSHA permissible exposure limit (PEL) or standard is also presented. Unless otherwise noted in the table, the NIOSH recommendations were originally published in criteria documents.

Note to Readers:

Copies of NIOSH publications are generally available from the U.S. Government Printing Office and the National Technical Information Service. Single copies of these publications may be obtained (while the supply lasts) from Publications Dissemination Division of Standards Development and Technology Transfer National Institute for Occupational Safety and Health 4676 Columbia Parkway Cincinnati, Ohio 45226 (513) 533-8287 Please enclose a self-addressed mailing label with your request.

Definitions of Abbreviations and Terms

Action level the exposure concentration at which employers must initiate certain provisions of the NIOSH recommended standard such as periodic measurements of worker exposure, training of workers, and medical monitoring

Ca    agent recommended by NIOSH to be treated as a potential human


CD criteria document

CFR Code of Federal Regulations

CIB Current Intelligence Bulletin

CNS central nervous system

dBA decibels measured on the A scale, which approximates the response of the human ear
ECG electrocardiogram

J/cm((2)) joules per square centimeter

um    micrometer

ug/m((3)) micrograms per cubic meter

mg/m((3)) milligrams per cubic meter

mppcf millions of particles per cubic foot

MSHA Mine Safety and Health Administration

mW/cm((2)) milliwatts per square centimeter

NIOSH National Institute for Occupational Safety and Health

nm    nanometer

OSHA Occupational Safety and Health Administration

PCBs polychlorinated biphenyls

PCDDs polychlorinated dibenzo-p-dioxins

PCDFs polychlorinated dibenzofurans

PEL permissible exposure limit (OSHA)

ppb parts per billion

ppm parts per million

REL recommended exposure limit (NIOSH)

(Skin) potential contribution to overall exposure by the cutaneous

route, including mucous membranes and eyes

TCDD 2,3,7,8-tetrachlorodibenzo-p-dioxin

TWA time-weighted average

WL working level

WLM working level month

NOTE TO SYSTEM USER: The remainder of this document is tabular and, therefore, not entered into telecommunication channels.


To request a copy of this document or for questions concerning this document, please contact the person or office listed below. If requesting a document, please specify the complete name of the document as well as the address to which you would like it mailed. Note that if a name is listed with the address below, you may wish to contact this person via CDC WONDER/PC e-mail.
For single issue purchase 800-843-6356
write to:CDC, MMWR MS(C-08)
Atlanta,, GA 30333

This page last reviewed: Wednesday, January 27, 2016
This information is provided as technical reference material. Please contact us at to request a simple text version of this document.