H2S is a toxic and flammable gas that smells like rotten eggs. It is colorless and in high amounts blocks the sense of smell. Exposure can cause irritation of eyes, nose, throat and lungs, and lead to death from respiratory failure. It is heavier than air so can accumulate in low areas. Personal protective equipment including respiratory protection is required for workers exposed to H2S. Proper safety procedures and emergency response are important when working with or rescuing victims of H2S exposure.

2. H2S is a very toxic gas. It has no color but it smells like rotten eggs. In
larger amounts, H2S quickly blocks the sense of smell.That is why odor
should never be used to rate H2S levels.
The gas irritate the eyes, nose, throat and lungs.Too much H2S can halt
the breathing center in the brain, which can cause death. It may be
possible to revive the victim, but only if first aid is given right away.
H2S dissolves in water and oil, and it may be released when these liquids
are heated, depressurized, or agitated.
Because H2S is heavier than air, in may settle in low spots.
This can pose risks when entering areas where the gas
May be present.
Hydrogen Sulfide

3. H2S burns and explodes easily. When it burns, H2S gives
of sulphur dioxide, another dangerous gas that is toxic,
strong smelling and irritating.
H2S often results from the bacterial break down of
organic matter in the absence of oxygen, such as in
swamps and sewers. It also occurs in volcanic gases,
natural gas and some well waters.

4. With high levels of H2S, poisoning can be swift and deadly –
with little warning. A worker who is not wearing protective
equipment may pass out quickly.The body may tremble and
death may follow in seconds or minutes as a result of breathing
failure.
At lower level of gas, the following symptoms may appear a
few minutes after exposure, or be delayed for several hours:
Eye irritation Headache Confusion
Breathing irritation Nausea Vomiting
Disorientation
H2SWarning Signs

5. Concentration In
Parts Per Million
(ppm)
Observations And Health Effects
Less than 1
3 to 5
20 to 150
150 to 200
200 to 250
Most people smell “rotten eggs”.
Odor is strong.
Nose and throat feel dry and irritated. Eyes sting, itch,
or watery. Prolonged exposure may cause coughing,
hoarseness, shortness of breath and runny nose.
Sense of smell is blocked (olfactory fatigue).
Major irritation of the nose, throat and lungs occurs,
Along with headache, nausea, vomiting and dizziness.
Prolonged exposure can cause fluid buildup in the lungs
(pulmonary edema), which can be fatal.

6. Concentration In
Parts Per Million (ppm) Observations And Health Effects
300 to 500
Above 500
Symptoms are the same as above but, more severe.
Death can occur within 1 to 4 hours of exposure.
Immediate loss of consciousness. Death is rapid,
sometimes immediate.

7. As a rule, if you smell H2S and don’t know how much of the
gas is in the air, leave the area right away. Return only when
the amount of the gas has been measured and found to be at
safe level. Never use odor to assess H2S levels.
Electronic Detectors – These range from small personal
samplers to large, stationary monitors. A display screen
shows the gas level. When H2S levels exceed a set limit,
These detectors sound an alarm, flash
A light or vibrate.
Detecting Hydrogen Sulfide

8. FLAMMABLE GAS. Burns with a pale blue flame. Form
explosive mixtures with air over a wide range.Very low
ignition energy. Ignites spontaneously at 260 deg C (500 deg
F). Leaking gas will be initially colder and heavier than air, and
may hug the ground and travel a considerable distance to a
source of ignition and flash back to a leak. During a fire,
irritating/toxic sulfur oxides (mainly sulfur dioxide) may be
generated. Can accumulate in confined spaces, especially in
low-lying, poorly ventilated areas, producing a
fire/toxicity/explosion hazard. Compressed gas. Heat from fire
can cause a rapid build-up of pressure inside cylinders, which
may cause explosive rupture and a sudden release of large
amounts of flammable gas or may cause cylinder to rocket.
Fire Hazard Summary

9. Extinguishing Media:
Carbon dioxide, dry chemical powder, water spray or fog.
Fire Fighting Instructions:
Extreme caution is required in a fire situation. Evacuate area
and fight fire from a safe distance or a protected location.
Approach fire from upwind to avoid extremely hazardous gas
and toxic decomposition products.
For fires involving flammable gases, the best procedure is to
stop the flow of gas before attempting to extinguish the fire. It
is extremely dangerous to extinguish the fire while allowing
continued flow of the gas.The gas could form an explosive
mixture with air and reignite, which may cause far more
damage than if the original fire had been allowed to burn.

10. extinguishing the fire with carbon dioxide or dry chemical
powder may be necessary to permit immediate access to
valves to shut off the flow of gas. However, this must be done
carefully. If it is not possible to stop the flow of gas and if
there is no risk to the surrounding area, allow the fire to
continue burning while protecting exposed materials with
water spray, to prevent ignition of other combustible
materials. Gas clouds may be controlled by water spray or
fog.

11. Protection of Fire Fighters:
Hydrogen sulfide is an extremely
toxic, flammable gas.The combustion
products of hydrogen sulfide (e.g.,
sulfur dioxide) are skin contact and
inhalation hazards. Do not enter
without wearing specialized
equipment suitable for the situation.
Firefighter's normal protective
clothing (Bunker Gear) will not
provide adequate protection.
Chemical protective clothing (e.g.
chemical splash suit) and positive
pressure self-contained breathing
apparatus.

12. Three types of PPE are used by workers at risk of exposure to H2S:
Escape Units
Air-line Units
SCBAs
*Remember, your respirator should always be positive-pressure to protect H2S from
entering your body!*
Personal Protection Equipment (PPE)

13. Before attempting to rescue anyone else:
Protect yourself
Put on breathing apparatus
Use the buddy system
If you are trained in first aid:
Check the victim for breathing
If victim isn’t breathing, administer rescue breathing
Then check for a pulse
If the victim has no pulse, begin CPR
Send victim for medical attention
Emergency Procedures

14. AMBATOVY SAYS YES TO SAFETY…
BE SAFE EV’RYONE…