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Over the years H2S has killed numerous workers in oil field and Petros-chemical industry. Many of the victims where completely unaware that the deadly concentration of H2S present as it is colorless and deadens the sense of smell at high concentration. <br>Its our responsibility to be aware of the properties and toxicity of H2S gas. We must be able to recognize its presence and protect our self from its lethal effects.<br>This PPT deals with properties and characteristic of H2S and appropriate emergency response actions to take should a H2S related incident arise.<br>
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The aims and objectives of the training are to ensure that the delegate: • Gains the required knowledge and understanding of the particular hazards and properties of H2S, • Appropriate emergency response actions to take should a H2S related incident arise. AIM & OBJECTIVE
To successfully complete this training delegates must able to explain: • Hydrogen sulphide – how it is formed and where it is found • Other names used to describe H2S • Properties and characteristics of H2S • Parts per million (ppm) as a measurement parameter • Occupational exposure limits to H2S • Factors affecting individual susceptibility to H2S • Types of detector equipment • Types of respiratory equipment • Pre-use checks of personal detection devices and EBA LEARNING OUTCOMES
To successfully complete this training delegates must able to demonstrate: (10) Operating personal H2S detection equipment (including checks) (11) Responding to an alarm (12) Donning & operating (including checks) an escape breathing apparatus (EBA) with a mask within 30 seconds (13) Donning & operating (including checks) an EBA with a hood within 30 seconds (14) Connecting to a pressurised cascade breathing system with an activated EBA which has been donned correctly (15) Disconnecting from a pressurised cascade breathing system with an activated EBA which has been donned correctly. LEARNING OUTCOMES
Practical: Explanations and demonstrations by Training Staff Practice by Delegates Demonstration by Delegates (Assessment by direct Observation) Written Assessment: Delegates will be given a 30 minute written exam on completion of the training. ASSESSMENT METHODS
DURATION OF THE TRAINING PROGRAMME The optimum contact time (including a refreshment break) is seen as 4 hours. ROLES OF STAFF Explain and facilitate understanding of slide presentation. To familiarise personnel with the correct use of different types of Emergency Breathing Apparatus (EBA) and detector. Assessment DURATION & STAFF ROLES
HOW IS HYDROGEN SULFIDE FORMED? • H2S is a formed by the decomposition of organic materials rich in Sulphur by bacteria in the absence of air • During the formation of Oil and gas H2S is simultaneously formed. • H2S is generated as a common by product of industrial and manufacturing process
1.1.1 WHERE IS HYDROGEN SULFIDE FOUND? Geothermal Environment Process platform /Refineries Dredging operation Sewer and sewage treatment facilities Leather Tanning Industry / Sugar / Paper pulp Mills Underground mining.
1.1.1 H2S COMMON NAMES • Sewer Gas • Swamp Gas (Marshy area) • Sour Gas • Stink Damp (mines) • Rotten egg gas • Sulfuretted Hydrogen
1.1.2 THE PHYSICAL PROPERTIES &CHARACTERISTICS OF H2S H2 S blocks O2 from bonding to RBC causing O2 Deprivation H2 S is also transported to the CNS by RBC. H2 S paralyze CNS. CNS cannot give inputs to respiratory system. Person stops breathing.
1.1.2 THE PHYSICAL PROPERTIES &CHARACTERISTICS OF H2S Poor Warning Characteristics Color less Paralysis Olfactory Nerve at Higher Concentration Rotten egg smell at low concentration Never rely on your nose for detecting H2S. Always use Personal Detector while working in H2S classified area.
1.1.2 THE PHYSICAL PROPERTIES & CHARACTERISTICS OF H2S • H2S + H2O H2SO4 • (eye / nose / throat irritation) • Soluble in water, sludge, drilling fluids, when temperature increases, pressure increases or agitated it get back to gaseous form • H2S can become soluble in drilling fluid and can come up without being detected. • The gas can be released from mud • Temperature change • Pressure change • Agitation by Shale shaker, degassers, or mud pits • Ph change
1.1.2 THE PHYSICAL PROPERTIES & CHARACTERISTICS OF H2S Air H2S 1.0 1.189 Heavier than Air Temperature Dispersed by wind Pressure
1.1.2 THE PHYSICAL PROPERTIES & CHARACTERISTICS OF H2S H2S can cause serious damage to metal used in the drilling and production, as well as the seals used to keep the fluids and pressure within the system • H2S + H2O H2SO4 (acidic environment) • H2S + Metal MetalSulphide • H2S + FeO Corrode and Pits metal Sulfide Stressed Cracking O2 When Pyrophoric Iron Sulphide particles are exposed to air, they are oxidized back to iron oxide generating a considerable amount of heat.
1.1.2 THE PHYSICAL PROPERTIES AND CHARACTERISTICS OF H2S Gasket, rubber, plastic • Stringent Planned Preventative Maintenance • Use of Corrosion resistant Alloy (SS with 31% Ni, 27 % Cr) • Crew Trained for identifying, reporting defects / hazards Think what H2S can do to our lungs??
1.1.2 THE PHYSICAL PROPERTIES & CHARACTERISTICS OF H2S LEL 4.3% UEL 46%. Burns with Blue flame H2S +O2 SO2 Low LEL (less room for error) Explosive at autoignition temperature (2600C or 5000F) Continuous ventilation / monitoring of H2S Hot work PTW
1.1.3 PARTS PER MILLION (PPM) MEASUREMENT PARAMETER Common units of measurements of gas percentage and PPM. Parts or units of gas present in one million units of air. 1% =10,000 PPM. (1 million divided by 100)
1.1.3 OCCUPATIONAL/WORKPLACE EXPOSURE LIMITS (OEL/WEL) Occupational Exposure Limit is an upper limit on the acceptable concentration of a hazardous substance in workplace air for a particular material OEL are set by competent national authorities and enforced by legislation to protect occupational safety and health.
1.1.3 COMMON DEFINITIONS ASSOCIATED WITH H2S OCCUPATIONAL/WORKPLACE EXPOSURE LIMITS (OEL/WEL) Long Term Exposure Limit (LTEL) which is the maximum exposure permitted over an 8-hour period.
1.1.3 OCCUPATIONAL/WORKPLACE EXPOSURE LIMITS (OEL/WEL) Short Term Exposure Limit (STEL) is the maximum exposure permitted over a 15-minute reference period.
1.1.3 OCCUPATIONAL/WORKPLACE EXPOSURE LIMITS (OEL/WEL) 1.1.4 Measurement and the OEL/WEL of H2S Immediate Danger to Life and Health (IDLH) The exposure at which hazard, such as a toxic gas, poses an immediate threat to health or life, would cause irreversible adverse health affects, or would interfere with your ability to escape a confined such environment / space unaided. For H2S IDLH is100 PPM
1.1.5 THE PHYSIOLOGICAL EFFECTS OF EXPOSURE TO H2S Primary Route of Entry is by INHALATION Exposure Duration (HOW LONG?) Exposure Concentration (HOW MUCH?) Frequency (HOW MANY TIMES?) Individual Susceptibility (IMMUNE SYSTEM) Age Drug/Alcohol Compatibility Physical Condition Smoker /Non-Smoker Body mass People with chronic lung disease may suffer those effects at a lower PPM.
1.1.5 THE PHYSIOLOGICAL EFFECTS OF EXPOSURE TO H2S If you experience physical symptoms, leave the area immediately, quickly get upwind and report it. Buddy System ?
1.1.6 HOW H2S IS DETECTED AND THE USE OF ONSITE & PERSONAL DETECTION EQUIPMENTNever Rely on your nose for detecting H2S
1.1.6 HOW H2S IS DETECTED AND THE USE OF ONSITE & PERSONAL DETECTION EQUIPMENT DIFFERENT TYPES OF DETECTORS ARE USED IN INDUSTRY Portable Detectors Fixed Detectors Personal Detectors
1.1.6 HOW H2S IS DETECTED AND THE USE OF ONSITE & PERSONAL DETECTION EQUIPMENT • Chosen location: based on the Risk assessment Potential area • where people are likely to be present • where H2S is likely to be released. • where H2S can collect • Continuous monitoring • Connected to Central Control Panel located in ECC. • Alert the crew, specify the location. • Low Alarm • High Alarm Fixed Detectors
1.1.6 HOW H2S IS DETECTED AND THE USE OF ONSITE & PERSONAL DETECTION EQUIPMENT Portable Detectors • Multi readings: • H2S, Oxygen, CO & LEL • Used for Gas testing Purpose • Used by Authorized personnel
1.1.6 HOW H2S IS DETECTED AND THE USE OF ONSITE & PERSONAL DETECTION EQUIPMENT Personal Detectors • Mandatory for entering in the H2S classified zone. • Used to ALERT the individual worker. • Ensure • Correct unit versus hazard • Battery Test • Function self-test • Bump test • Wearing position
1.1.7 ACTIONS TO BE TAKEN IN THE EVENT OF AN ALARM On hearing the alarm: Take immediate action as time is of the essence when dealing with exposure to H2S • Essential personnel to perform their duties as per the station bill. • Non essential personnel shall make the way to muster station. • Report the causality or person left behind if you have seen any. Hold your Breath No Inhalation No Exhalation Upwind Escape route Don EBA. Proceed to muster station STOP WORK
1.1.8 THE TYPES OF RESPIRATORY EQUIPMENT AND THE IMPORTANCE OF CORRECT FIT OF THE FACE MASK Common problems with respirator use and getting a correct fit. • Facial hair • Corrective Spectacles • Contact lenses • Psychological Disturbances (Claustrophobia) • Sealing Problems (scars, hollow temples, very prominent cheekbone, deep scar creases, lack of teeth or denture.)
1.1.8 THE TYPES OF RESPIRATORY EQUIPMENT Escape Unit Escape / Working Unit Rescue /Working Unit • Designed to be quickly and easily donned in an emergency • Not be used to effect a rescue or to accomplish any task • Only for escape from hazardous zone. Air Purifying Respirator (APR) Chemical Cartridge Respirators Protection against contaminants in the air for 10-15 minutes Never use this unit to approach a hazardous zone.
1.1.8 THE TYPES OF RESPIRATORY EQUIPMENT Escape Breathing Apparatus (EBA) Duration: 15 minutes Only for Emergency Escape EBA with Hood EBA with Mask Connect EBA with air cascade system and close EBS cylinder valve.
1.1.8 THE TYPES OF RESPIRATORY EQUIPMENT Supplied Air Breathing Apparatus (SABA) Buddy System Barricade Supervised
1.1.8 THE TYPES OF RESPIRATORY EQUIPMENT Rescue Unit / Working Unit Self Contained Breathing Apparatus (SCBA) Used for Rescue / prolonged activities Duration: 30 Minutes / 45 Minutes / 60 Minutes
1.1.9 THE ROLE OF RESPONSE TEAMS IN AN H2S EMERGENCY AND USE OF SCBA. RESCUE WILL BE COMPLETED BY THE EMERGENCY RESPONSE TEAM OR OR NEVER ATTEMPT A RESCUE IN AN AREA THAT MAY CONTAIN HYDROGEN SULFIDE WITHOUT USING APPROPRIATE RESPIRATORY PROTECTION AND WITHOUT BEING TRAINED TO PERFORM SUCH A RESCUE.
SUMMARY Rotten egg smell at low concentration Highly toxic Flammable Auto ignition 500 0F Colourless Air H2S Dispersed by wind Pressure Temperature Soluble in water / drilling fluids Heavier than Air Corrosive
H2S EXPOSURE PROTECTION TIPS H2S classified zones Gas test Identify Source of Danger SSOW Drills Ventilation Safety Equipment Location
FOLLOWING EXPLANATION AND DEMONSTRATE BY TRAINING STAFF, DELEGATES TO PRACTICE AND DEMONSTRATE 1.1.10 H2S personal detection equipment – pre-use checks & operation 1.1.11 Responding to an alarm 1.1.12 EBA fitted with a mask – pre-use checks & operation 1.1.13 EBA fitted with a hood – pre-use checks & operation 1.1.14 Method of connection to a pressurised cascade air supply with an activated EBA which has been donned correctly 1.1.15 Method of disconnection from a pressurised cascade air supply with an activated EBA which has been donned correctly.
