Juler Group Presents Hydrogen Sulfide (H 2 S) Safety JG Juler Group 2005 Juler Group Incorporated
Objectives To provide summary knowledge of the hazards of working around H 2 S To provide summary knowledge of proper protection in an H 2 S environment
Dangers of H 2 S See video at http://julergroup.com/resource_oilandgas a refinery employee received a fatal exposure to hydrogen sulfide gas while draining the contents of a knockout drum to an oily water sewer, rather than activating a closed system to pump out the drum. The worker failed to observe procedures calling for the use of a closed system, and the valve to the sewer was not locked out. The accident was associated with opening a valve to a sewer cup during the draining of a fuel gas knockout drum in a hydro treating unit of a petroleum refinery. Normal work procedures included periodically opening a valve that carried a water-gas mixture to a separator which removed and vented hydrocarbon gases to a flare
Properties Invisible and Colorless Rotten egg odor (conc. as low as 0.13 ppm) Heavier than air - may accumulate in low-lying or poorly ventilated areas, particularly if the air is cold, there is little air movement, or there is a heavy fog. Toxic - may cause death (conc. 250 ppm) Explosive and Flammable (auto-ignition point of 518º F and a flammable range from 4.3 to 46% in a mixture with air) Corrosive Water and Oil soluble
Effects Irritant H 2 S plus water = acid Burning eyes, sore/scratchy throat, coughing, respiratory irritation Acid in lungs attacks alveoli and they burst Pulmonary Edema (blood & puss in lungs) Death Lungs & Breathing H 2 S binds to the Red Blood Cell (RBC) - blocks Oxygen Oxygen deprivation Blood & Brain H 2 S-RBC attacks respiratory control center in brain Slows it down - then shuts it down Sense of smell is deadened Never trust nose to detect H 2 S smell Death in 3-5 minutes (1000ppm conc)
Regulatory Limits OSHA Ceiling Limit There is no PEL too toxic Ceiling limits may not be exceeded C = 20 ppm C = 20 ppm OSHA Short Term Exposure Limit (STEL) average exposure over a 10 minute period of maximum exposure during a single work shift. STEL = 20 ppm STEL = 20 ppm View OSHA Table Z-2
Symptom Checklist (Memorize) Burning Eyes Sore Throat Respiratory Irritation Coughing Headache Dizziness Nausea Fatigue Confusion Loss of sense of smell STOP & Memorize Note: not all will be experienced by each person
Explosive & Flammable By-products of H 2 S fire Sulfur Dioxide (SO 2 ) OSHA Permissible Exposure Limit (PEL) 5 ppm (per table Z-1) Highly Toxic Suffocating Burns the Lungs Reactivity SO 2 plus Water = Sulfuric Acid
Corrosion H2S corrodes carbon steel readily Weakens carbon steel causing brittleness and breakage Oxidation (i.e. rusting) forms Iron Sulfide Scale (Black Scale) Flashes (i.e. sudden burst of flame) upon drying and exposure to air A serious hazard while working on pipelines, flow lines, tanks, etc.
Monitoring Personal Monitors Small, convenient, easy to use Monthly bump check Yearly calibration Use Wear on hip with sensor head exposed! Alarm triggered at 10ppm know your alarm! Keep your monitor operational Fixed Monitors Found on rigs, well sites, refineries, storage, etc. Alarm triggered at Ceiling Limit Alarm consists of sounds and lights Alarm goes off MOVE TO SAFE AREA IMMEDIATELY
Precautions Wind Direction and Velocity Pay attention to Wind Socks or Flags Alarm sounds retreat cross-wind to safe area RUN Gas Well wind RUN
RESCUE Protect YOURSELF first and foremost Assist others second Training Rescue training required Buddy System required CPR and First Aid training required H 2 S environment training required Certified Personal Protective Equipment (PPE) Communicate, Communicate, Communicate Notify Emergency Medical Services (EMS) Immediately Follow Emergency Action Plan (EAP) Follow Company Policy on Rescue Never Rescue unless you can DO IT RIGHT
Personal Protective Equipment (PPE) Respiratory PPE POSITIVE PRESSURE SUPPLIED AIR (no other allowed) Constant flow of air in mask Positive pressure pushes air out of leak spots in mask Grade D air not pure oxygen Three Types Escape Pack (5-minute Tank) with bag or tight fitting face piece NOT FOR RESCUE, WORK or TESTING! Work Unit (Supplied Air Respirator S.A.R.) = 5-minute Tank + Mask + 300 supply line + compressor/cascade Rescue/Testing Self Contained Breathing Apparatus (S.C.B.A.) = Mask + Harness + 2216psi Tank Note: 30 minute air pack will NOT last 30 minutes
Respirator Types Escape S.A.R. S.C.B.A.
Respiratory Protection (cont) ONLY Positive Pressure Supplied Air in an H2S environment Maintain your equipment! Employer responsibility to provide BUT your responsibility to maintain OSHA requires FIT Testing every year Should ensure apparatus works when it counts Two types of FIT Tests Qualitative checks quality using smoke or odorant Quantitative check uses a pump system and computer to assign a FIT number Medical exam or M.E.Q. performed prior to FIT Test M.E.Q. is questionnaire reviewed by PLHCP FIT Test Failures No facial hair except very neatly trimmed mustache, no beards
Respiratory Protection (cont) FIT Testing (cont) FIT Test Failures Facial Hair note that no facial hair except very neatly trimmed mustache is allowed Glasses Mask sizing and typing Jewelry Grease or dirt Facial structure Training Get trained Employee & Management to have good attitude Get bi-lingual training if necessary Be Safe