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Detect Carbon Monoxide

There are several goverment organizations and professional organizations that have posted recommended exposure limits to Carbon Monoxide (mostly for the work place). There is no single listing of all of these limits, and so we’ve tried to summarize many of them on this page.

First, here are descriptions of some of the organizations that publish these limits. Click on the logos to visit their official websites.

Occupational Health and Safety Administration (OSHA) – A Federal agency under the Department of Labor that develops and enforces federal standards for health and safety in the work place.

Diesel Exhaust
Diesel Exhaust Hazard Alert

OSHA
National Institute for Occupational Safety and Health (NIOSH) – A Federal agency under the Department of Health and Human Services that trains occupational health and safety professionals, conducts research on health and safety concerns, and tests and certifies respirators for workplace use. NIOSH
American Conference of Governmental Industrial Hygenists (ACGIH) – An organization of professional industrial hygiene personnel in government or educational institutions. The ACGIH develops and publishes recommended occupational exposure limits each year called Threshold Limit Values (TLV’s) for hundreds of chemicals and physical agents. ACGIH
American Society of Heating, Refrigerating, and Air Conditioning Engineers (ASHRAE) – An international trade association that provides information and sets standards for the uniform testing and rating of heating, ventilation, air conditioning, and refrigeration equipment. ASHRAE
Environmental Protection Agency (EPA) – A part of the US federal government that enforces environmental laws and provides information and guidance to policy makers. EPA

Each organization has its own vocabulary to describe the type of limit or level. Here is a summary of some commonly seen terms:

The table below summarizes some of the most up-to-date exposure limits, including their date of publication.

Limit /
Level
Type Organization Industry
/ Area
Sources Date
9 PPM
TWA
(8 Hours)
EPA General
http://www.epa.gov/air/criteria.html Web page authored:
8/2007
9 PPM
TWA
(8 Hours)
World Heallth
Organization
General (Outdoor)
http://www.who.int/ipcs/publications/ehc/en/ehc_213_part_1.pdf,
page 19.
1999
9 PPM
Ceiling
ASHRAE
General
(Living Areas)
ASHRAE
Unknown
25 PPM
TWA
(8 Hours)
ACGIH General
2004 ACGIH Handbook
of TLVs and BEIs
2004
35 PPM
TWA
(1 Hour)
NIOSH General
http://www.osha.gov/dts/chemicalsampling/data/CH_225600.html
Web page authored:
6/2004
35 PPM
TWA
(1 Hour)
EPA General
http://www.epa.gov/air/criteria.html
Web page authored:
8/2007
50 PPM
OSHA PEL as TWA
(8 Hours)
OSHA General
http://www.osha.gov/dts/chemicalsampling/data/CH_225600.html
Web page authored:
6/2004
50 PPM OSHA PEL as TWA
(8 Hours)
OSHA Construction http://www.osha.gov/dts/chemicalsampling/data/CH_225600.html Web page authored:
6/2004
50 PPM OSHA PEL as TWA
(8 Hours)
OSHA Maritime http://www.osha.gov/dts/chemicalsampling/data/CH_225600.html Web page authored:
6/2004
125 PPM
Excursion Limit (EL)
ACGIH
General
Based on definition
of EL in 2004 ACGIH Handbook, and the fact that there is no defined
STEL for CO in this handbook.
2004
200 PPM
Ceiling NIOSH
General
http://www.osha.gov/dts/chemicalsampling/data/CH_225600.html
Web page authored:
6/2004

For more information on Carbon Monoxide, and the health effects associated with different concentrations, click here.