Authorised Gas Tester Competence Training Package [PDF]

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AUTHORIZED GAS TEST (AGT) TRAINING



INTRODUCTION TO GAS TESTING



Gas testing involves testing for toxic and flammable gases using portable gas detection equipment, and is an integral part of establishing a safe system of work in the offshore oil and gas industry. Gas tests are performed to ensure that the environment in which we work is safe from the hazards of combustible or toxic gases, and that the worksite contains sufficient oxygen such that it is safe to breathe. AGTs are responsible for performing these duties for a facility in accordance with specified precaution. AGTs are formally authorized (as demanded by today's training) as competent to carry out gas testing in a facilities.



REQUIREMENT FOR BEING AN AGT An AGT must; • Must have successfully completed the authorized gas tester training course with 70% pass of class work • be able to demonstrate the ability to survey potentially hazardous areas using the detection equipment available and have been assessed as competent. •Be able to demonstrate the use of a BA set in a confined space and have been assessed as competent • Be aware of the capabilities and limitations of gas test equipment



WHEN IS GAS TESTING REQUIRED



• As specified on the applicable risk assessment and/or permit e.g. hot work of any type where heat is used or generated including welding, flame cutting, grinding, etc. • Where work may cause an uncontrolled release of hydrocarbons, other flammable or toxic materials. • Where electrical instrumentation work which may cause sparks will be used in a hazardous area. • Where there will be entry into a confined space • For gas alarm investigations.



REGULARATORY BACKUP FOR GAS TESTING



LIFE SAVING RULES • How many Life Saving Rules does the Shell Group have? • Could you mention the Life Saving Rules related to Gas



testing and Confined space entry?



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The 12 Life Saving Rules Rule #1 Work with a valid Work Permit when required A Work Permit describes what you must do to stay safe. You should  Understand the Work Permit and follow it  Confirm that the Work Permit is valid  Confirm with the Supervisor or the person in charge of the work that it is safe to start work.



If you are the Supervisor or the person in charge of the work you should  Confirm if a Work Permit is required for this work.  Confirm that the workplace has been inspected before work starts  Explain how the Work Permit keeps you safe  Confirm the Work Permit is signed  Confirm that it is safe to start work.  Get a new Work Permit when the work or the situation changes  Confirm that the work is completed



Rule #2 Conduct gas tests when required Air is tested to stop explosions and/or make sure you can breathe the air safely. You should  Confirm with the Supervisor or the person in charge of the work that the air is tested  Confirm with the Supervisor or the person in charge of the work it is safe to start work  Stop work if you smell gas



If you are a Gas Tester you should  Understand which tests the Work Permit requires and how often  Use certified equipment for the tests



If you are the Supervisor or the person in charge of the work you should  Confirm that gas testing is carried out as per Work Permit  Request more gas tests if necessary  Confirm that it is safe to start work.



Rule #3 Verify isolation before work begins and use the specified life protecting equipment Isolation separates you from danger, such as electricity, pressure, toxic materials, poisonous gas, chemicals, hot liquids or radiation to keep you safe. Specified life-protecting equipment by the Work Permit, such as breathing apparatus, electrical arc flash protection or chemical resistant suits protect you from danger.



You should  Understand the isolations that protect you from danger  Confirm with the Supervisor or the person in charge of the work that isolations are in place  Confirm with the Supervisor or the person in charge of the work it is safe to start work.



If you are the Supervisor or the person in charge of the work you should  Confirm isolation is in place, for example, lock switches, separate pipes with spades, or lock access doors  Confirm no stored energy or other dangers remain  Confirm that it is safe to start work.



Rule #4 Obtain authorisation before entering a confined space A confined space, such as a vessel, tank or pipe can contain explosive gas, poisonous air or other dangers such as, a lack of oxygen, things that can fall on you or you can fall from. Authorised access keeps you safe. You should  Confirm with the Supervisor or the person in charge of the work that it is safe to start work.



 Confirm with the Attendant that you can enter a confined space  Follow the requirements of the Work Permit



If you are an Attendant you should  Approve and control access to a confined space  Have means of communication with people in the confined space



If you are the Supervisor or the person in charge of the work you should Confirm that the requirements of the Work Permit are in place  Confirm that a qualified Attendant is always present when people are in a confined space  Confirm that gas testing is carried out as per Work Permit  Confirm that it is safe to start work.



Rule #5 Obtain authorisation before overriding or disabling safety critical equipment Safety-critical equipment must work correctly to keep you safe. Examples of safety-critical equipment include isolation devices/emergency shut down valves, trip systems, relief valves, fire and gas alarm systems, certain level controls, alarms, crane computers, and In-Vehicle Monitoring Systems.



You should  Obtain authorisation from the Supervisor before overriding or disabling safety -critical equipment



If you are the Supervisor you should  Point out the safety-critical equipment in your work place.  Confirm the authorisation comes from the right level



Rule #6 Protect yourself against a fall when working at height



Rule #7 Do not walk under a suspended load



Rule #8 Do not smoke outside designated smoking areas



Rule #9 No alcohol or drugs while working or driving



Rule #10 While driving, do not use your phone and do not exceed speed limits



Rule #11 Wear your seat belt



Rule #12 Follow prescribed Journey Management Plan



SUMMARIES Why are we here? • Life Saving Rules # 1- 5 have to do with today’s training • The work environments you work in are capable of ending your life and that of others within minutes: Remember Iriama. • The work environments you work in are capable of causing damage to assets worth millions of Dollars. • This training can save your job. How many people have been consequence managed since 1st July 2009 on account of the 12 LSRs? • What is your take?



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GAS TESTING & MONITORING



Introduction to Gas Hazards



What is Gas? • The name gas comes from the word chaos which indicates disorder • Gas is a swarm of molecules moving randomly and chaotically; constantly colliding with each other and anything else around it. • Gases fill any available volume and due to the very high speed at which they move will mix rapidly into any atmosphere in which they are released



What is Gas? Different gases are all around us in everyday life. • The air we breath is made up of several different gases including Oxygen and Nitrogen • Natural Gas (Methane) is used in many homes for heating and cooking • Car exhausts produce gases which contain Carbon Monoxide and Carbon Dioxide



What is Gas? Gases can be lighter, heavier or about the same density as air



Gases can have an odour or be odourless



Gases can have colour or be colourless



PROPERTIES OF GASES Behaviors of Gases; Behavior of gases is governed by • gas properties and • environment It is difficult to predict the behavior of gas releases. Explosive air/gas mixtures can occur at varying heights and locations within a plant. How ever particular attention should be paid to areas around pipe work joints, valves, tank inlet/outlet, vents and drains and all areas adjacent to this.



The behavior of gas releases will depend upon : • the environment and • on whether the gas was released slowly (e.g as an evaporating liquid) or • as a high pressure escape from a leak such as a flange failure. A clear understanding of the nature of a gas release and its probable behavior is essential to ensure that effective representative measurements are obtained. NOTE; Gas releases are therefore generally affected by the following factors/ * Their relative density at the points of release * Gas velocity of release * Gas temperature at point of release * Air current * Evaporation



Gas Hazards 1.



There are three main types of gas hazards Flammable – Risk of fire and or explosion, e.g. Methane, Butane, Propane



2.



Toxic – Risk of poisoning, e.g. Carbon Monoxide, Hydrogen Sulfide, Chlorine



3.



Asphyxiant – Risk of suffocation, e.g. Oxygen deficiency, Nitrogen, Carbon Dioxide



Flammable Risk • Fire Triangle Three factors are always needed to cause combustion:



FIRE Fuel



1. A source of ignition 2. Oxygen/Air 3. Fuel in the form of a gas or vapour



Flammable Risk 100% v/v gas 0% v/v air



• Each gas / air mixture is ignitable over it‟s flammable range



too rich



flammable range



U.E.L. (upper explosive limit) L.E.L. (lower explosive limit)



too lean 0% v/v gas 100% v/v air



Flammable Risk Only Gas, No Air



UEL



Stoichiometric Point



Ideal mixture



LEL Only Air, No Gas



Power of explosion



SOME DEFINITIONS LEL = LOWER EXPLOSIVE LIMIT



Definition: LEL: is the lowest amount/concentration of a gas/vapor in the atmosphere that is capable of igniting when there is an ignition source e.g., LEL for methane is 5% (v/v) UEL = UPPER EXPLOSIVE LIMIT UEL: is the highest concentration of a gas in the atmosphere that is capable of igniting when there is an ignition source e.g., UEL for methane is 15% (v/v)



Stoichiometric point



Is the point in the ideal mixture range where we have the best mixture of fuel/gas and oxygen for a complete combustion



% LEL AND % UEL OF SOME AGT SUBSTANCES Substance



Formula



LEL (VOL %)



UEL (VOL %)



Acetone



CH3CHO



2.15



13.0



Acetylene



C2H2



2.4



88.0



Butane



C4H8



1.5



8.5



Ethane



C2H6



3.O



15.5



Ethylene



C2H4



2.7



34.0



Hexane



C6H12



1.2



7.4



Hydrogen



H2



4.0



75.6



Methane



CH4



5.0



15.0



Propane



C3H8



2.0



9.5



Flash Point • Flash Point (F.P. oC) – The flash point of a flammable liquid is the lowest temperature at which the surface of the liquid emits sufficient vapour to be ignited by a small flame. – Don‟t confuse with Auto-Ignition Temperature as the two can be very different:



Gas / Vapour Methane Kerosene Bitumen



Flash Point OC Ignition Temp. OC ambient changes flammable limits • O2 depletion caused by: – – – –



Displacement Combustion Oxidation Chemical reaction



Oxygen Enrichment • It is often forgotten that Oxygen enrichment can also cause a risk. • At increased O2 levels the flammability of materials and gases increases. • At levels of 24% items such as clothing can spontaneously combust. • Oxyacetylene welding equipment combines oxygen and acetylene gas to produce an extremely high temperature. • Leaks from the O2 cylinders is the main hazard. • Sensors have to be specially certified for use in O2 enriched atmospheres.



Relative Density Relative density: is a measure of the density of a gas relative to the density of air. It is an indication of the buoyancy of a gas i.e., whether it is heavier or lighter than air.



• Helps determine sensor placement • The density of a gas / vapour is compared with air when air = 1.0 • Vapour density < 1.0 will rise • Vapour density > 1.0 will fall



Relative Density of Gases GAS



CHEMICAL FORMULA



DENSITY(AIR=1)



Hydrogen



0.07



Methane



0.54



Ammonia



0.6



Hydrogen cyanide



0.93



Carbon Monoxide



0.97



Ethylene



0.97



Air



1.0



Nitric Oxide



1.04



Ethane



1.05



Formaldehyde



1.07



Methylamine



1.08



Hydrazine



1.1



Methanol



1.1



Oxygen



1.1



Hydrogen Sulphide



1.18



Ethylene Oxide



1.5



Carbon Dioxide



1.5



Propane



1.55



Butane



2.1



Ether (diethyl)



2.5



Hazardous Area Classification



Area Classification • There are certain parts within the restricted Areas where the presence of flammable mixtures are more likely than others • These areas have been divided into 3 Zones or Divisions • The classification is based on the likelihood of occurrence and duration of a flammable atmosphere



Area Classification •Two main systems are used:



–Europe / IEC –North America (NEC 505 / 500)



Continuous hazard



Intermittent hazard



Possible hazard



(>1000hrs/annum)



(>10 instrument is charging • Red LED lights stay on -> instrument is fully charged • 4 hours are needed for a complete charge



Do not charge underground or in areas, where explosions can occur! There is a danger of explosion! The chargers are not designed in accordance with the regulations for fire and explosion protection..



BATTERY CASE POWER SUPPLY •



Loosen the screw with the help of a Allen key



•



Remove the battery case



•



Insert the 2 alkaline- or NiMh batteries



•



Pay attention to the polarity of the batteries



•



Install the battery case and tighten the screw



Do not charge the battery in explosion hazard areas. Alkaline-Batteries are part of the Ex-approval. Only the following types should be used: Energizer No. E91 Energizer No. EN91 Varta Type 4106 The use of alkaline batteries other than those described above invalidates the intrinsic safety approval for the instrument and could result in unsafe operation.



OVERVIEW OF THE ICONS



 Special symbols provide a quick message about the instrum Error Icon Notice Icon PEAK / Maximum Value Icon TWA Value Icon STEL Value Icon



Bump Test Icon Fresh Air Calibration Icon 1-Button-Calibration Icon Span Calibration Icon Password-Protected Menu Battery Icon



THANK YOU FOR YOUR ATTENTION!



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Regulations; both local and international • Occupational Safety & Health Administration(OSHA) – standard 29 CFR 1910.134 • Confined Space regulations 1997. • The Management of Health and Safety at Work Regulations 1999. • The Control of substances Hazardous to Health Regulations 2002. • The Provision & Use of Equipment Regulations 1998 • Mineral Oil Safety Regulations (MOSR) 1997 • Factories Act No. 16 of 1987 – Requires that personnel be adequately protected from respiratory hazards 2/25/2011



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A breathing or respiratory hazard exist when a toxic contaminant is present in the air at a high enough level to cause harm when it is inhaled. The damage may occur immediately or it may take years for effects to show up An immediate breathing hazard also exists when the air does not contain enough oxygen to support life.  Three (3) groups of respiratory hazards:  Hazardous substances: Particulates, Vapours, Sprays Mists, Fogs, Smoke, Gases, Dusts  Confined Spaces  Toxic or Oxygen deficient environment



It is necessary to use respiratory protection (respirators) when working in environments with such respiratory hazards. 2/25/2011



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Full Mask



(A) SAR



(B) SCBA



[II] Atmosphere Supplying Respirators 2/25/2011



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The Occupational Safety & Health Administration has set standards for worker respiratory protection All respirator filter cartridges must have the certification from recognized institutions



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Medical Evaluation: OSHA Regulations require that a medical evaluation be conducted to determine the respirator user’s capability to perform their anticipated work tasks while wearing respiratory protection. Fit testing: OSHA Regulations require that Fit Testing be conducted to ensure that the respirator properly fits the individual using the respirator. Medical evaluation and fit testing are required annually for respirator users 2/25/2011



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When must a respirator be used? • If a label states a respirator must be worn when using the chemical or material • If the work environment contains dusts, vapour, mists, fumes etc that pose a health hazard • If the work environment lacks breathable air 2/25/2011



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• Do not use for protection against air contaminants other than those listed on the cartridge. • Do not use a respirator when conditions prevent a good face-piece seal. • Respirators do not provide protection to exposed areas of the body • APR (Respirators) do not provide protection when working in a toxic environment. 2/25/2011



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Breathing Apparatus Set (Set Description & Ancillary Equipment)



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Open Circuit or Closed Circuit • Open Circuit • Breathing apparatus type in which the exhaled air is released into the ambient. There are two basic types:  The ‘Demand Type’( Negative Pressure) and  The ‘Pressure Demand Type’



•



The demand type only supply air on demand • The pressure demand or positive pressure type supplies a steady stream of air to stop toxic fumes or smoke from leaking into the mask



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• Closed Circuit • Breathing apparatus type to which the exhaled air is recirculated. There are two types: • The ‘compressed or Liquid Oxygen type’, and • The ‘Oxygen – generating type’.



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Parts of a B.A. Set The Face Mask • Parts of the Face Mask  Visor  Outer –Mask  Inner – Mask  Face Mask Straps  Neck Strap  Speech Diaphragm  Demand Valve  Second Stage Reducer  Auto-First Breath Mechanism  Pre-Doffing Anti- Pressure Leak Button 2/25/2011



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BASIC CHECKS



(Pre – Operation Checks)



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Introduction • Prior to use of set it is very important to carry out required checks • Failure to carry out such checks could lead to undesired exposure in the irrespirable atmosphere • The check consist of the following: - Physical checks - High Pressure checks - Low pressure checks



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Conclusion • All the above necessary checks should be done and confirmed okay. • The set can then be coupled preparatory for donning and • After donning same checks should be carried out to prepare the set for next donning operation



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Basic B.A. Arithmetic



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Introduction •



The duration of use for any B.A. set depends on two key functions:







The air content of the cylinder and







The breathing rate of the wearer



•



For safe use of equipment it is important to ascertain the following:



1. 2. 3.



Full content Work duration Safety margin



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Recall Physiology of Respiration • When air is taken in the primary gas needed by man in the process is oxygen and carbon dioxide is expelled. • The demand for oxygen is dependent on the activity which the person is engaged in at the time of demand



• Anxiety, fear can lead to increase in air demand. • On the average a man walking briskly takes in about 37.3 litres of air per minute. • For practical purpose this Value is rounded up to 40 litres per minute. 2/25/2011



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B.A. Capacity • Every B.A. Set is charged to a given cylinder capacity usually at 14.7psi. • The cylinder capacity in bars could be 200bar, 250bar, and 300bar. • Every cylinder has a water capacity in litres (9L, 7L etc.) • The cylinder capacity in relation to the consumption capacity of the person determines the work duration of the cylinder. 2/25/2011



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Basic Calculations • Full Duration: Cylinder capacity x average water capacity Average human air consumption.



So for 200bar cylinder = 200 x 9 = 45 minutes 40



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Basic Calculations • Work Duration: The available time for the wearer to perform a given task = full duration – safety margin.



For 200bar cylinder, the work duration ‘w’ = (45 – 10)minutes = 35minutes.



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Basic Calculations • 170bar = 28mins.



• 180bar = 30mins. • 190bar = 33mins. • 200bar = 35mins. • 250bar = ? • 300bar = ?



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CONFINED SPACE ENTRY



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Group Standards and Requirements • The Hazard and Effects Management Process (HEMP) shall be applied for confined space entry (CSE) activities. The HEMP shall include the following steps: -Identification of the hazards; -Assessment of the risks using the Risk Assessment Matrix (RAM); -- Detailed analysis of the hazards, e.g. by job hazard analysis (JHA), in case of activities assessed as high or medium risk on the RAM; -- Description of the necessary controls and recovery measures. -If a generic HEMP exercise and the guidance in this document have been incorporated into CSE procedures, the job specific HEMP shall focus on identifying the controls and recovery measures for the particular CSE and location; -• The HEMP shall demonstrate that alternatives to entering the space have been considered and that all reasonably practicable steps have been taken to eliminate asphyxiant, flammable, toxic and other hazards; -• The CSE criteria for oxygen, toxic and flammable levels and for breathing apparatus in Section 7.0 of this document are mandatory;



-• A rescue plan shall be prepared and implemented for every CSE; 2/25/2011 -• Every CSE shall be authorised and controlled by a permit to work.



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CONFINED SPACE ENTRY The Factories Act No. 16 of 1987 , the MOSR of 1997 require the employer to comply with any specific regulations that apply to work in dangerous or potentially dangerous areas. The Shell companies, and OSHA have elaborate guidelines and recommended practices for controlling Health, Safety and environment hazards during Confined space Entry (CSE). Other Relevant Regulations UK. Based. Confined Space regulations 1997. The Management of Health and Safety at Work Reg. 1999. The Control of substances Hazardous to Health Reg. 2002. The Provision & Use of Equipment Reg. 1998 2/25/2011



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TESTING CONFINED SPACES Testing of a confined space must be carried out before it is certified as been save to enter. The test should check for the presence of gas or toxic fumes and the adequacy of the supply and content of oxygen. NOTE; an acceptable result must be obtained before work in any confined space proceeds. One common way of practically making a confined space safe for entry is by PURGING OR INERTING. Purging could mean introducing external air or use of an inert gas so as to deplete confined space of toxic or hazardous gases.



One common problem with INERTING is that it could yield to further oxygen deficiency. Where possible all tests in confined spaces should be conducted from outside. Where this is impractical the following basic rule should be adhered to when entering a confined space for any activity; * * * *



wear approved Breathing Apparatus Know what type of gas or vapors to be expected Ensure all isolations to the confined space have been implemented Use gas tester with a probe



CONFINED SPACE ENTRY Definitions/ Key persons involved in CSE activities Confined Space: Fully or partially enclosed space with a risk of serious injury from hazardous substances or conditions within the confined space. (CSE) may be complete body entry, or inserting a head into man way openings, hatches, pipe ends etc. Permit To Work (PTW) principal authorisation/clearance document signed by a Competent Person(s) for all nonroutine or potentially hazardous activities to be carried out in restricted Areas under stated and accepted precautions with designated Action Parties for the enforcement of compliance. Attendant(Standby) : outside the confined space, and is responsible for assisting the entrant in exiting the confined space, and calling for emergency assistance when required. 2/25/2011



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CONFINED SPACE ENTRY Definitions/ Key persons involved in CSE activities Entrant: The person who enters a confined space. The safety representative: is the qualified person who evaluates the hazards, prescribes required equipment and precautions and issues the Confined Space Entry Permit. Operations supervisor: (Permit Issuer), who is responsible for making sure that the confined space is safe for entry, and that the supervisor in charge of the work and the attendant are fully familiar with the hazards, controls and recovery measures; Supervisor: (Permit Holder), in charge of the work who is responsible for making sure that the workers comply with the controls specified on the permit, and for providing means of rescuing persons from the space in case of an emergency; 2/25/2011



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Examples of Confined Spaces: • Tanks • Manholes • Boilers • Furnaces • Sewers • Silos • Hoppers 2/25/2011



• Vaults • Pipes



• Trenches • Tunnels



• Ducts • Bins • Pits 151



CONFINED SPACE ENTRY CSE Hazards. What are the dangers expected from CSE?



1. Oxygen Deficiency. Normal 2. Oxygen Enrichment.( O2 > 21.5%) 3. Fire explosion 4. Presence of Toxic gases or fumes 5. Residues left in the space (process materials) 6. Physical Hazards 7. Unsafe conditions(Nature of work, moving machinery parts, close contact, egress during emergency, Hot conditions, etc) 8. Ingress of material(faulty isolation, collapse, fluids/solids, etc) 9. Accumulation of dust in the space. 10.Psychological issues 11. Biological hazards 2/25/2011



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CONFINED SPACE ENTRY The Law (MOSR, Factories Act, the Management of Health and Safety at Work Regulations 1999 stipulates to carry out sufficient Risk Assessment for all work activities for determining what measures are necessary for safety. This in most cases will include assessment of: • • • • •



The task to be carried out The environment Working materials and tools Suitability(competences)of those carrying out the task Arrangement for emergency rescue.



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CONFINED SPACE ENTRY CSE CONTROLS A. Appointment of competent persons and adequate training and instruction of employees as required. B. Avoid entry into confined spaces through work planning C. If entry is unavoidable, follow a system of work e.g. PTW D. Put in place adequate emergency arrangements before work starts. Elaborately this may mean: 1. Isolation: Mechanical/electrical.(LOTO, physical isolation, etc) 2. Clearance of process materials before entry 3. Checking size of entry 4. Ventilation 5. Testing of air (Gas testing/ Monitoring) 2/25/2011



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CONFINED SPACE ENTRY CSE CONTROLS



6. Provision of special tools and lighting. 7. Provision of BA 8. Emergency planning (Prepared rescue plan, Rescue harness, Communication, checking how alarm is raised, first Aid, rescuers etc) 9. A valid PTW for the work 10. Shut down 11. Control of Ignition Sources 12. Control of radiation Sources 13. Control of Internal Combustion Engines and Cylinders 14. Personal Protective Equipments



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CONFINED SPACE ENTRY CSE Recovery & Emergency Management. •



Access and Escape



•



Attendant



•



Rescue Team



•



Rescue plan



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CONFINED SPACE ENTRY



A means must be provided for both safe normal entry or exit , and emergency extrication. Tripods with hoist, lifeline, and full body harness are often used for emergency extrication.



Ladders may be used for ordinary entry and exit.



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RESCUE PLAN



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