CAW National Council 4000
Occupational Health and Safety

Hazardous Substances:  Hydrogen Sulphide

Hydrogen sulphide can create ill-health effects if it is inhaled, swallowed, or if it comes in contact with eyes, skin, nose or throat.

Short-Term Effects

Inhalation of high concentrations of hydrogen sulphide vapor may cause loss of consciousness and death. Inhalation of lower
concentrations may cause headache, dizziness, fatigue, irritability, insomnia and upset stomach. Exposure to hydrogen sulphide can
cause temporary loss of the sense of smell, and irritation of the eyes, nose, or throat.

Long-Term Effects

Prolonged exposures to low concentrations may cause bronchitis, pneumonitis, runny nose, and sore throat.

Repeated exposure results in increased susceptibility so that eye irritation, cough and systemic effects may result from
concentrations previously tolerated without any effect.


Enclose process
Local exhaust ventilation
General dilution ventilation
Personal protective equipment


ACGIH TLV 10 ppm (14 mg/m3).
U.S. NIOSH recommended 10ppm (14 mg/m3), 10 minute maximum

(See also CAW Fact Sheet on
Sulphuric Acid)

Source:  CAW Health, Safety & Environment Department