ON A STILL, QUIET MORNING IN OCTOBER 1980, A BLOW OUT OCCURRED ON AN OFFSHORE DRILLING DR ILLING RIG IN THE ARABIAN GULF. WITHEN MINUTES, NINETEEN MEN WERE DEAD.
...ALL VICTIMS OF
H2S THE INVISIBLE KILLER H 2S (hydrogen sulfide gas or “sour gas”) is found wherever sour crude oil or gas is handled. H 2S is a potentially deadly partner in the oil and and gas industry. Yet, through safe handling and proper training, the risk of personal injury from H 2S can be virtually eliminated. What YOU LEARN about this poisonous and flammable gas MAY SAVE YOUR LIFE, LIFE , or the life of your friend?
WITH PROPER TRAINING, EQUIPMENT AND PROCEDURES, YOU CAN WORK SAFELY IN H 2S AREAS.
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Hydrogen sulfide gas: The invisible killer H 2S or hydrogen sulfide gas is a leading cause of SUDDEN DEATH in the work place. Such deaths are very rare, but they can happen if proper precautions are not taken. H 2S is present during almost every phase of petroleum and gas production and processing at ARAMCO. Whether you work on a drilling rig or at the Ras Tanura refinery, at a GOSP or a gas plant, you probably work near a source of hydrogen sulfide gas.
Normally, H 2S is safely contained within the vessels and lines, which store or carry ARAMCO products. For this reason, there is only a small risk of exposure to deadly amounts of this gas. But human error or equipment failure can cause a gas leak in your work area, and therefore you have a NEED TO KNOW:
What is H 2S? And
How does H 2S harm you? Hazardous properties of the gas Poisonous effects on the human body
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Where is H 2S present? And
How and when can H2S? ? You “detect” H2S High risk areas in ARAMCO Gas detector instrument Explanation of parts per million Continuous H 2S monitors Confined space entry ARAMCO POCKET GUIDE ON HEALTH HAZARDS
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Hydrogen sulfide gas: The invisible killer H 2S or hydrogen sulfide gas is a leading cause of SUDDEN DEATH in the work place. Such deaths are very rare, but they can happen if proper precautions are not taken. H 2S is present during almost every phase of petroleum and gas production and processing at ARAMCO. Whether you work on a drilling rig or at the Ras Tanura refinery, at a GOSP or a gas plant, you probably work near a source of hydrogen sulfide gas.
Normally, H 2S is safely contained within the vessels and lines, which store or carry ARAMCO products. For this reason, there is only a small risk of exposure to deadly amounts of this gas. But human error or equipment failure can cause a gas leak in your work area, and therefore you have a NEED TO KNOW:
What is H 2S? And
How does H 2S harm you? Hazardous properties of the gas Poisonous effects on the human body
Page 4 8
Where is H 2S present? And
How and when can H2S? ? You “detect” H2S High risk areas in ARAMCO Gas detector instrument Explanation of parts per million Continuous H 2S monitors Confined space entry ARAMCO POCKET GUIDE ON HEALTH HAZARDS
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What can you do in a Gas emergency? And
How can you protect Yourself and rescue others? Emergency response plan Respiratory protection Scott - air Pak Rescuing an H 2S victim Reviving an H 2S victim
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What is H2S? H 2S Hydrogen sulfide is a highly toxic colorless transparent gas heaver than air.
HAZARDOUS PROPERTIES OF THE GAS POISONOUS: Hydrogen sulfide is an extremely poisonous, or toxic, gas. A single breath of high concentrated H 2S can paralyze your breathing system and is enough to kill a grown man. The amount you inhale determines the effect on you: EXTREMLY SMALL AMOUNTS of H 2S smell strongly of rotten eggs, but otherwise are harmless. Slightly higher amounts burn your eyes, nose and throat and cause dizziness and nausea along with vomits SMALL AMOUNTS of H 2S gas in air rapidly deaden your sense of smell, loss of consciousness and Death may occur in less than one hour. MODERATE AMOUNTS of H 2S paralyze your Breathing system: a victim will die within minutes unless he is rescued and normal breathing restored. Therefore… THE No. 1 HAZARD OF H 2S IS DEATH BY INHALATION SMELLS FOUL: H 2S smells like rotten eggs. This odor is so distinctive that one might think the smell would warn you of dangerous amounts. However, H 2S deadens your sense of smell, so you must never rely on your nose to check if a vessel or an area is free of hydrogen sulfide.
CAUTION: ODOR IS NOT A REL RELIABLE WARNING
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INVISIBLE: H 2S Hydrogen Sulfide gas is colorless. The danger is that LEAKS MAY NOT BE SEEN. H 2S has killed many people who entered areas they thought “looked safe”. HEAVIER THAN AIR: Some gases are lighter than air and rise when released, but H 2S tend to sink into low-lying areas such as pipe trenches, valve boxes, sumps and sewers , excavations and around rig platforms. In confined spaces, H 2S settles to the bottom, forming a deadly gas Layer. In windy or foggy weather H 2S moves as invisible cloud, usually in the direction the wind is blowing to accumulate in low places in dangerous concentration. Windsocks at work sites show you the wind direction.
Whereas a moderate FLAMMABLE AND EXPLOSIVE : amount of H 2S in air rapidly poisons, high concentrations of gas in air are extremely flammable and explosive. When hydrogen sulfide burns, it produces another very dangerous gas, sulfur dioxide (SO2). A sour gas leak may travel some distance to a source of ignition and flash back. Therefore open flames must be extinguished, heat-producing equipment including car engines must be switched off, and frictional or electrical sparking must be avoided when there is a flare outage or suspected gas leak. CORROSIVE: H 2S combines with moisture in air to form corrosive acid, which embrittles metal and eats away pipes, valves and other equipment. Gas leaks can occur when corroded lines fail: one more good reason for carrying out through inspections and regular maintenance.
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IMPORTANT FACT TO LEARN AND REMEMBER ABOUT H 2S: HYDROGEN SULFIDE IS DANGROUS BECAUSE IT IS
DANGER
EXTREMELY POISONOUS
DANGER
In high concentrations, a single breath can paralyze your respiratory center and kill you.
DEADENING TO YOUR SENSE OF SMELL
The “rotten-egg” smell is not a reliable warning
INVISIBLE Leaks cannot always be seen.
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HEAVIER THAN AIR H 2S tends to sink and accumulate in low-lying areas.
FLAMMABLE AND EXPLOSIVE
Very high mixtures of sour gas in air are a fire hazard.
CORROSIVE
H 2S is acidic: it irritates the eyes, mucous membranes, and corrodes lines and vessels.
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How does H 2S harm you? POISONOUS OR TOXIC EFFECTS ON THE HUMAN BODY When hydrogen sulfide is inhaled it goes from the lungs into the bloodstream immediately. There, small amount of H 2S are quickly broken down into harmless compounds. But moderate amounts will rapidly overpower the body’s Defense system. Moderate amounts of H 2S soon paralyze the breathing control center in the brain: lungs cease to function, death from asphyxiation follows in minutes. H 2S is poisonous in such low concentrations that we measure the amount of gas in air in parts per million, usually written “ppm”.
The concentration of H 2S in the air 1 ppm 10 ppm
Determines
The effect on your body
Rotten egg smell is noticeable Safe work limit for an 8-hour shift
WEAR A SCOTT AIR PAK AT LEVELS ABOVE 10 PPM 20 ppm 150 ppm
Irritates eyes and throat. Deadens sense of smell.
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350 ppm 600 ppm
40,000 ppm 4%
Fatal in less than one hour without Scott Air Pak Rapid loss of consciousness, breathing stops, death within minutes THIS CONCENTRATION COULD OCCUR IN ARAMCO DURING A GAS EMERGENCY EXPLODES AND BURNS.
Remember, H 2S is dangerous in very small quantities. It really takes very little to kill you.
Where is H2S present? HIGH RISK AREAS H 2S is formed when organic matter rots or decomposes, just as petroleum and other hydrocarbons were formed millions of year ago. This explains both the rotten smell of H 2S and why sour gas is associated with most crude oil and natural gas. H 2S is also a common contaminant in mining, leather tanning, fish processing and chemical manufacturing. Hazardous sour gas atmospheres are common in sewers, tunnels, mines and wells.
At ARAMCO, H 2S hydrogen sulfide gas is present at most operating areas, from the well site producing sour crude, through the processing and treatment plants, to the oil tankers at the terminals.
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MOST ARABIAN CRUDES ARE SOUR
Almost every producing field in Saudi Arabia yields “sour” crude, that is, crude oil containing H 2S hydrogen sulfide. Some of the operations at risk therefore include:
Drilling and workover…
GOSPs and gas plants ARAMCO POCKET GUIDE ON HEALTH HAZARDS
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… and spheroids. TYPICAL ARAMCO worksites where YOU are at risk from poisonous gas:
Swinging a blind or breaking a flange
…working on or near a leaking valve or a faulty seal…. ARAMCO POCKET GUIDE ON HEALTH HAZARDS
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… or maintenance work in gas compression area.
CONFINED SPACE ENTRY is often made into H 2S risk Area. This might include pumps, vessels, valve boxes, pipe, trenches, or sewers. ARAMCO POCKET GUIDE ON HEALTH HAZARDS
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Poison gas emergencies may be the result of flare outage. …
…or a well blowout during drilling operations. IT’S YOUR LIFE, BE AWARE OF THE H2S HAZARDS AT YOUR WORKSITE
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How can you “detect” H 2S? PORTABLE, HAND-OPERATED “DETECTORS” ARE FOR ROUTINE USE ONLY, NOT FOR WHEN A MASSIVE LEAK OCCURS PURPOSE OF THE 3-IN-1 GAS MONITOR, MODEL LTX310:
The LTX-310 3-In-1 gas monitor is a solid-state, multi-purpose gas detector. It monitor for H2S, flammable gases, and oxygen level. You can replace the H2S sensor with different sensors to detect others toxic gases. Before you issue a work permit, use the LTX310 to test for combustible gases, toxic gases, and oxygen levels. Use the LTX-310 and SP-402 sampling pump with the extendible probe to test in confined spaces and in areas that are difficult to get to. Use the LTX-310 in the leather belt case and shoulder strap to test the area around you continuously.
GAS DETECTOR TUBES: There is one type of hand- operated detector used at ARAMCO, it is made by DRAGER, it measures parts per million of H 2S in air, and it consists of a hand pump and glass detector tubes. The detector tubes contain chemical granules, which change color when air containing hydrogen sulfide is pulled through the tube by the hand pump. The DRAGER detector can be ordered from ARAMCO stock:
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DRAGER makes detector tubes for several different gases. Be sure to use the tube for H 2S, which measures 5-60 ppm. S/N 21-323-181 detector tubes for H 2S. S/N 21-323-000 bellows hand pump USE ONLY DRAGER TUBES WITHEN DRAGER HANDPUMP
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SP-402 Sampling Pump This is the battery-powered sampling pump you usually use with the LTX-310. A nickel-cadmium rechargeable battery pack or a lithium battery pack powers the detector. Visual and audible alarms warn you of low flow and low battery condition.
The hand aspirator is a constant-flow hand pump you can use it instead of the SP-402 battery-powered pump to draw in gas samples. The testing procedure for each type of detector is as follow: BEFORE EACH TEST, check the SP-402 for leaks: 1. Start the SP-402 and block the air inlet with your finger. 2. Observe for audible alarm warn you of low flow. If the alarm displayed, it does not leak. 3. Compress the hand pump and insert an unbroken tube. 4. Release the hand pump and observe for 1 minute. If the pump remains compressed, it does not leak. ARAMCO POCKET GUIDE ON HEALTH HAZARDS
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TO TEST FOR H 2S FIRST BREAK OFF BOTH ENDS Of the glass detection tube. (1) Insert the arrow end of the Drager tube into the bellows pump. (2) Hold the detector at the lowest position to sample; squeeze 10 times, allowing the hand pump to re-inflate fully between each Squeeze. The length of color change in the tube corresponds to a reading in parts per million, or “ppm”, marked in the tube.
What is a “part per million?” It is difficult to comprehend how small concentrations expressed in parts per million really are. Compare a one-gallon can to a million gallon holding tank. The gallon then represents one part per million (ppm). In fact, if you stacked up 10,000 of these one-gallon cans, all together they can hold only one percent of the holding tank! That is, there are 10,000 ppm in one percent.
If you write parts per million in terms of percentage, then 0.015% (150 ppm) H 2S deadens your sense of smell 0.06% (600ppm) is RAPEDLY FATAL, and 4% (40,000 ppm) H 2S in air explodes and burns. ARAMCO POCKET GUIDE ON HEALTH HAZARDS
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ARAMCO LOSS PREVENTION recommends the following ACTION to be taken when certain levels of H 2S are detected with glass detector tubes or LTX-310 devise: BELOW 10
Safe to work, but REMEMBER TO TEST AGAIN because conditions can change.
10 PPM
This is the maximum safe working limit for hydrogen sulfide.
ABOVE 10
WEAR A SCOTT AIR PAK and report the concentration to your supervisor.
ONLY TRAINED CERTIFIED OPERATORS SHOULD PERFORM GAS DETECTION TESTS Training in the use of LTX-310 devise and DRAGER gas detection instrument is available from ARAMCO LOSS PREVENTION (call 8752464 or 8748425 in Dhahran, 6738902 In Ras Tanura and 572-8280 in Abqaiq, Udhailiyah 5776560). ARAMCO G.I 2.100 outlines work permit requirements and details how and when to test for hydrogen sulfide. Loss Prevention’s Work Permit Training Course instructs in the Proper use of gas detectors. NOTE: UDHAILIYAH LOSS PREVENTION is conducting refresher courses in Work permit and gas testing in addition you can develop your self by visiting gas testing & work permit CBT (course basic training) sights in loss prevention safety courses at <> online learning.
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OTHER MEANS OF DETECTION FIXED CONTINUOUS H 2S MONITORS are installed in ARAMCO operational areas, which have a high risk of H 2S release. These monitors consist of a detector, or sensing head, beacon blue light and a horn installed out in the plant, and an indicating meter and alarm inside the plant control room. When H 2S levels exceed the safe limit, a signal passes from the detector to the meter and an alarm is sounded in the control room and plant area. Continuous monitor MUST be regularly checked and maintained, or they may fail to sound an alarm when a gas release occurs. Routine maintenance also decreases the chance of a false alarm from the monitor.
(1) Monitors must be checked by a qualified instrument technician.(faulty monitors should be reported to be fixed immediately) (2) A known concentration must be used to calibrate the monitor. (3) A regular schedule must be observed to calibrate the monitors. Keep a record of Calibration dates inside the control (4) When a monitor is being tested, EVERY PERSON in the area should be informed that a Test, and not an actual gas emergency, is in progress. ARAMCO POCKET GUIDE ON HEALTH HAZARDS
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PORTABLE: continuous H 2S monitors can be worn or carried. These detectors measure H 2S concentration electrically, and have an audio alarm that sounds when Levels above 10 ppm are detected.
LTX-310 devise or detector tubes are to be used: (1) When you suspect a gas leak: WEAR A SCOTT AIR PAK FOR PROTECTION WHEN AN H 2S LEAK IS SUSPECTED The detector tubes or LTX-310 devise help you pinpoint the source of gas leak so it may be repaired.
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(2) When you must enter a CONFINED SPACE to Work a confined space is any enclosed place or area having limited means of entry and exit. This includes tanks, columns, towers, pipelines, Sewers, sumps, valves boxes, and excavations. H 2S Hydrogen sulfide is only one of several life-threatening hazards, which may be present in a confined space. You may not enter a confined space at ARAMCO until the requirements of the confined space Work Permit and Form 924-4 have been satisfied. This permit requires that a certified person check for:
FLAMMABLE HAZARDS OXYGEN DEFICIENCY TOXIC HAZARDS A certified employee is one who has successfully completed ARAMCO LOSS PREVENTION’S Work Permit and Gas Test Training Courses.
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FLAMMBLE HAZARDS OF CONFINED SPACE One flammable hazard is the combustible residue called Pyrophoric Iron Sulfide. Traces of this unstable compound are often left behind when a vessel containing sour crude is drained. Hydrocarbon vapors are also flammable hazards in confined spaces.
The instrument used to test for flammable gas or vapor is called LTX-310. It measures in percentage of the lower explosive limit (LEL) of a flammable gas or vapor.
PURPOSE OF THE 3-IN-1 GAS MONITOR, MODEL LTX-310: The LTX-310 3-In-1 gas monitor is a solid-state, multi-purpose gas detector. It monitor for H2S, flammable gases, and oxygen level. You can replace the H2S sensor with different sensors to detect others toxic gases. Before you issue a work permit, use the LTX310 to test for combustible gases, toxic gases, and oxygen levels. Use the LTX-310 and SP-402 sampling pump with the extendible probe to test in confined spaces and in areas that are difficult to get to. Use the LTX-310 in the leather belt case and shoulder strap to test the area around you continuously. ARAMCO POCKET GUIDE ON HEALTH HAZARDS
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OXYGEN DEFICIENCY: If the air in a confined space contains less than 20 % (percent) oxygen, there is an “oxygen deficiency”. Attempting to work in such an atmosphere may result in loss of consciousness and death. For this reason, confined space must also be proceeding. An oxygen detector like this one is used by a certified operator.
There are TOXIC HAZARDS IN CONFINED SPACES: several toxic (poisonous) gases, including H 2S, and also toxic sludge and scales, left in vessels that contained sour crude or its products.
ARAMCO’s work permit for CONFINED SPACE ENTRY (green permit form No.924-4) list safety precautions to be followed before work is allowed. If there is a chance of H 2S exposure in the area, LTX-310 or glass tubes detector must be used as described. For H 2S detection in a confined space: 1. Wear a Scot Air Pak and a safety belt with a lifeline attached. 2. Test each compartment in the confined space, using the LTX-310 or a new tube for each test. 3. Perform gas tests more than once during the operation. Stirred up sludge may release H 2S. ARAMCO POCKET GUIDE ON HEALTH HAZARDS
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WHAT CAN YOU DO IN A GAS EMERGENCY? EMERGENCY RESPONSE, RESPIRATORS, RESCUE AND REVIVAL Each operation at ARAMCO, whether drilling rig, gas plant, refinery or tank farm, should have an EMERGENCY RESPONSE PLAN FOR H 2S release. The plan will differ depending on the operation, but basically each operation employee MUST KNOW how to: (1) SOUND AN ALARM to warn other people in the area. (2) DO A BREATHING APPARATUS to protect himself and the others immediately. (3) RESCUE AND REVIVE ANY VICTEMS OF H 2S. (4) EVACUATE TO AN UPWIND OR CROSSWIND LOCATION after checking the wind direction. (5) INVESTIGATE THE LEAK AND SHUT OFF THE SOURCE OF GAS RELEASE.
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To avoid panic when a gas emergency occurs, regular EMERGENCY DRILLS are essential. Workers MUST be trained in the use of the breathing apparatus BEFORE an Emergency occurs. YOU MUST BE AWARE of the meaning of warning lights and alarms at your worksite. YOU MUST KNOW the location of Scott Air Paks in your work area. YOU MUST KNOW where the windsock is so you can tell at a glance which way an H 2S cloud is likely to move. Employees must attend the safety orientation conducting in the operation-training center. DRILL MUST BE PRACTICED IN ASERIOUS AND PROFESSIONAL MANNER RESPIRATORS USED IN ARAMCO
FOR ESCAPE ONLY: The Scott 15-minutes Emergency Escape Breathing Apparatus is to be used in a gas emergency ONLY for evacuating the hazardous area. Also the 5-minutes escape bottle shown at the top of the next page provides ONLY enough air to allow evacuation. DO NOT use either for rescue or emergency maintenance. ARAMCO POCKET GUIDE ON HEALTH HAZARDS
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Drilling rigs have airline respirator systems, which include a 5 minutes escape bottle. In the event of a gas emergency, disconnect the airline hose and evacuate using the escape bottle. If you must rescue a fellow worker, use the escape bottle to reach the nearest Scott Air Pak upwind of the gas release. Don the Scott Air Pak before attempting rescue. ARAMCO POCKET GUIDE ON HEALTH HAZARDS
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IN GAS EMERGENCY, YOUR MOST IMPOTANT PIECE OF PROTECTIVE EQUIPMENT IS A SCOTT AIR PAK SCOTT AIR PAK: TRAINING AND REGULAR DRILLS ARE ABSOLUTELY ESSENTIAL FOR THE CORRECT USE OF THE BREATHING APPARATUS. You must learn how to don the cylinder and harness, check the air supply….
… and adjust the mask for an airtight face fit.
Quality maintenance of each Scott Air Pak is essential to prevent unwanted deterioration. ARAMCO POCKET GUIDE ON HEALTH HAZARDS
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Check for cracks in the face seal, broken head straps, cracked or clogged hoses. Cylinders must also be checked to ensure they are full of air and ready for use. It is very important that all these checks be recorded and dated. FOR TRAINING WITH SCOTT AIR PAKS, CALL ARAMCO FIRE PROTECTION DEPT. 87-53602 OR ABQAIQ TRAINING CENTER 572-8280. Remember, ONLY a Scott Air Pak should be used to rescue a victim of hydrogen sulfide, or to perform emergency maintenance to repair a gas leak. KNOW THE LOCATION OF ALL SCOTT AIR PAKS AT YOUR WORKSITE. THIS KNOWLEDGE MAY SAVE YOUR LIFE!
How can you protect yourself and rescue others? WHEN YOU SEE A MAN IS DOWN, and you suspect an H2S leak:
FIRST: SOUND AN ALARM CALL FOR HELP ARAMCO POCKET GUIDE ON HEALTH HAZARDS
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SECOND: Check the wind direction, and then head for the nearest Scott Air Pak which is either upwind or crosswind o f the victim.
ALWAYS DON A SCOTT AIR PAK BEFORE GOING TO THE RESCUE.
If you forget this basic rule, you may yourself fall victim to H 2S Hydrogen sulfide in your attempt to rescue someone else. ARAMCO POCKET GUIDE ON HEALTH HAZARDS
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When you have a good face seal and have checked your air supply, then pull the victim either upwind or crosswind into a safe area.
SPEED IS ESSENTIAL: ONCE YOU DON YOUR SCOTT AIR PAK, PULL THE VICTIM OUT OF THE CONTAMINATED AREA AND BEGIN MOUTH-TO- MOUTH RESUSCITATION ARAMCO POCKET GUIDE ON HEALTH HAZARDS
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Reviving an H 2 S victim: Almost all victims of H 2S will have stopped breathing and require resuscitation. Begin mouth-to-mouth resuscitation as soon as you are out of the contaminated area. A DELAY OF JUST FIVE (5) MINUTES IS FATAL
Tilt the victim’s head and lift the neck to open the airway.
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Pinch the victim’s nostrils closed, take a deep breath and blow into his mouth, giving four quick breaths followed by one breath every five seconds. Watch to see his chest rise as air fills his lungs.
Turn your head and listen for the victim to exhale. Repeat giving breaths every five seconds until the victim recovers. ARAMCO POCKET GUIDE ON HEALTH HAZARDS
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