H2S RemindersHydrogen Sulfide Can Kill You

Effects of Hydrogen Sulfide

Effects of Hydrogen Sulfide

• H2S is classed as a chemical asphyxiant, similar to carbon monoxide and cyanide gases. 

• It inhibits cellular respiration and uptake of oxygen, causing biochemical suffocation.

• Death may be immediate.

Harmful Effects of Hydrogen SulfideTypical Exposure SYMPTOMS

Low 0-10 ppm• Irritation of the eyes, nose and throat

Moderate 10-50 ppm

• Headache • Dizziness • Nausea and vomiting • Coughing and breathing difficulty

High 50-200 ppm

• Severe respiratory tract irritation • Eye irritation / acute conjunctivitis • Shock • Convulsions • Coma • Death in severe cases

Prolonged Effects of Hydrogen Sulfide

• Prolonged exposures at lower levels can lead to:

o Bronchitiso Pneumoniao Migraine headacheso Pulmonary edemao Loss of motor coordination

Wherever possible, exposure should be minimised by employing adequate engineering

controls and safe working practices. 

Deployment of Gas Monitors

• Deployment Plano Position of GM (drawing)o Timetable (time it takes to measure)o Accessories (fans, tripods, etc)o Personnel (trained specialists in...)

• Entry into areas that may have possible H2S exposure will be prohibited until precise gas readings are taken

• Official and formal "SAFE WORKING CONDITIONS" must be declared before work can begin.

The use of direct reading gas detection instrumentation should be required before entering well sites and confined

spaces that could contain an accumulation of H2S gas.

• Should a co-worker ever be overcome by H2S gas: 

o Do not attempt a rescue until you are properly protected yourself. Use proper PPE including SCBA and mechanized ventilation. 

o The rescuer can very easily get caught out by venturing into a confined space without adequate protection. 

o Remember that at levels above 200 ppm, collapse, coma and death due to respiratory failure can occur within seconds after only a few inhalations so you can be overcome yourself very quickly. 

o Such incidents are sadly all too common and only serve to make the rescue effort twice as difficult.

Procedures when H2S is detected

• When H2S is detected:o Emergency Procedureso Restrict area (Tape)o Sound Alarmo Check wind directiono Deploy & Activate:

SCBA Ventilation Rescue Harness Mechanical Lift Standby Person