Chlorine

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Overview
NIOSH Chemical Resources
Related NIOSH Resources
Selected Publications
Related Resources
International Resources

Overview

CAS No. 7782-50-5

Chlorine (Cl₂) is a greenish-yellow gas with a pungent, irritating odor. Exposure to low levels of chlorine can result in nose, throat, and eye irritation. At higher levels, breathing chlorine gas may result in changes in breathing rate and coughing, and damage to the lungs. Additional symptoms of exposure to chlorine can be severe. Workers may be harmed from exposure to chlorine. The level of exposure depends upon the dose, duration, and work being done.

Chlorine is used in many industries. It’s used in the pulp and paper industries, pool chemical products, cleaning products, mining products, bleach and plastics manufacturing. Some examples of workers at risk of being exposed to chlorine include the following:

Workers in water treatment and sewage facilities
Agricultural workers who clean livestock facilities, such as dairy farms
Workers who clean pools
Janitorial workers who use cleaning products
Factory workers in bleach and plastic manufacturing

NIOSH recommends that employers use Hierarchy of Controls to prevent injuries. If you work in an industry that uses chlorine, please read chemical labels and the accompanying Safety Data Sheet for hazard information. Visit NIOSH’s page on Managing Chemical Safety in the Workplace to learn more about controlling chemical workplace exposures.

The following resources provide information about occupational exposure to chlorine. A useful search terms for chlorine include “molecular chlorine.”

NIOSH Chemical Resources

NIOSH Pocket Guide to Chemical Hazards

The NIOSH Pocket Guide to Chemical Hazards (NPG) helps workers, employers, and occupational health professionals recognize and control workplace chemical hazards.

Manual of Analytical Methods

The NIOSH Manual of Analytical Methods (NMAM) is a collection of methods for sampling and analysis of contaminants in workplace air, and in the blood and urine of workers who are occupationally exposed.

Health Hazard Evaluations

The Health Hazard Evaluation Program (HHE) conducts onsite investigations of possible worker exposure to chemicals. Search the HHE database for more information on chemical topics.

Related NIOSH Resources

Documentation for Immediately Dangerous to Life or Health (IDLH) Value Profile: Chlorine—Documents the criteria and information sources that have been used by NIOSH to determine immediately dangerous to life or health concentrations.
NIOSHTIC-2 search results on Chlorine—NIOSHTIC-2 is a searchable database of worker safety and health publications, documents, grant reports, and journal articles supported in whole or in part by NIOSH.
NIOSH Worker Health Study Summaries—NIOSH conducts research to prevent illnesses and injuries in the workplace. The NIOSH Worker Notification Program notifies workers and other stakeholders about the findings of these research studies.

Selected Publications

NIOSH Criteria Documents: Criteria for a Recommended Standard: Occupational Exposure to Chlorine—DHHS (NIOSH) No. 76-170 Contains a recommended standard for mitigation of exposure to Chlorine to prevent adverse effects over a working lifetime.
Immediately Dangerous to Life or Health Value Profile: Chlorine Pentafluoride—DHHS (NIOSH) No 2016-170

Related Resources

International Resources

Page last reviewed: June 26, 2018, 02:25 PM

Content source: National Institute for Occupational Safety and Health