Hydrogen Chloride Summary

Expected Concentrations:

Hydrogen chloride can be measured during all methamphetamine "cooks". Time-weighted average concentrations typically range from 0.02 ppm to 20 ppm. The peak level measured by National Jewish Medical Center during one controlled "cook" with a real-time monitor was 155 ppm. Current standards for hydrogen chloride exposures are as follows:





Ceiling 5.0 ppm

Ceiling 5.0 ppm

Ceiling 2.0 ppm

50.0 ppm

General Health Effects:

Exposures to hydrogen chloride can cause acute and chronic health effects. The primary effects from acute exposure are usually irritation of the upper respiratory track due to the high solubility of hydrogen chloride. These exposures usually result in the exposed individual quickly leaving the area. Exposure may cause cough, burning throat, and choking. Irritation is frequently confined to the nose throat and larynx, and unless escape is hindered, inflammation is the primary result. If escape is prevented, laryngeal spasm or pulmonary edema may result. (1)

One individual exposed during a swimming pool cleaning effort developed severe bronchospasm and asthma. Workers exposed to as little as 10.0 ppm of hydrogen chloride experienced work impairment, above 50 ppm work was hindered and above 100 ppm work was impossible. Ten subjects that were exposed to less than 1.8 ppm of hydrogen chloride were found to have no significant pulmonary effects. (2)

Individuals exposed to hydrogen chloride levels above 4.6 ppm were found to have some dental erosion that may have been caused by the exposure. As an airway irritant, hydrogen chloride has been shown to cause irritant-induced bronchoconstriction and airway hyper-responsiveness in some workers. Hydrogen chloride is also a strong irritant of the eyes, mucous membranes, and skin. (2)

Health Risks to Children: Children with exposures to hydrogen chloride are likely to have similar symptoms as do adults. Children may be more susceptible to pulmonary damage due to a greater lung surface area per body weight and a more rapid breathing rate. The health effects may also be more pronounced due to narrower air passages in the lungs.

Fetal Health Effects: There are no known human fetal health effects from parental exposure to hydrogen chloride, however, rats exposed to hydrogen chloride during pregnancy had a higher fetal mortality than did rats not exposed to hydrogen chloride.


Proctor, N.H. , Hughes, J.P. 1978. Chemical Hazards of the Workplace. J.B. Lippincott Co. Philadelphia, PA  533 pp.

ACGIH. 2003. Documentation of the ACGIH TLV’s Hydrogen Chloride. American Conference of Governmental Hygienists. Cincinnati, OH.

Salocks, C. and Kaley, K.B. Technical Support Document:  Toxicity Clandestine Labs: Methamphetamine. Vol 1. , Number 3. Hydrogen Chloride. Cal/EPA. Office of Environmental Health Hazard Assessment. Sacramento, CA . 2003. 10 pp.

Additional Information:

Technical Support Document: Toxicology Clandestine Drug Labs: Hydrogen Chloride
Office of Environmental Health Hazard Assessment

Chemical Information: Hydrogen Chloride
International Programme on Chemical Safety