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 <-20 38 270
595 210 310
Auto-Ignition Temperature • The auto-ignition temperature or kindling point of a substance is the lowest temperature at which it will spontaneously ignite in a normal atmosphere without an external source of ignition, such as a flame or spark. • Apparatus for use in a hazardous area must not have a surface temperature that exceeds the ignition temperature • EX1b apparatus are EXplosion proof
Toxic Risk • Some gases are poisonous and can be dangerous to life at very low concentrations. • Some toxic gases have strong smells like the distinctive „rotten eggs‟ smell of Hydrogen sulphide H2S(. • Others are completely odourless like Carbon Monoxide (CO).
Toxic Risks • A toxic gas that is a risk in the home is CO. • CO is a product of incomplete combustion in power generating set at home. • Fireplaces
Toxic Risk • The unit of measurement most often used for the concentration of toxic gases is parts per million (ppm). • For example 1ppm would be equivalent to a room filled with a total of 1 million balls and 1 of those balls being red. The red ball would represent 1ppm.
1 million balls
1 red ball
Toxic gas limits & terminology • Time Weighted Average (TWA) – Toxic gas limits related to concentration & time
• Short Term Exposure Limit (STEL) – The maximum allowable concentration over 15 minutes.
• Long Term Exposure Limit (LTEL) – The maximum allowable concentration over an 8 hour period.
• Permissible Exposure Limit (PEL) – is the maximum amount/concentration of a chemical that a worker may be exposed to under OSHA regulation.
Toxic gas limits & terminology contd. • PEL-TWA – The average amount of a chemical that a worker can be exposed to 8 hours a day, 5 days a week.
• Units of measure – Parts per million (ppm) – Milligrams per cubic metre (mg/m3)
• Levels – COSHH (Control of Substances Hazardous to Health Regulations) – OSHA (Occupational Safety and Health Administration) – NIOSH (National Institute for Occupational Safety and Health)
Effects of exposure to Carbon Monoxide PPM CO
Time
Symptoms
35
8 hours
The maximum exposure allowed by OSHA in the workplace over an eight hour period.
200
2-3 hours
Slight headache, tiredness, fatigue, nausea and dizziness.
400
1-2 hours
Serious headache-other symptoms intensify. Life threatening after 3 hours.
800
45 minutes Dizziness, nausea and convulsions.
1600
20 minutes Headache, dizziness and nausea. Death
3200
5-10 minutes
Headache, dizziness and nausea. Death within 1 hour.
6400
1-2 minutes
Headache, dizziness and nausea. Death within 25-30 minutes
Unconscious within 2 hours. Death within 2-3 hours. within 1 hour.
12,800 1-3 min
Death
Effects of exposure to Hydrogen Sulphide PPM H2S
Time
Symptoms
10 - 20
2 hrs +
Eye Irritation, headache, and nausea
50 - 100
1 hr +
Slight eye and respiratory tract irritation
200 - 300
1 hr +
Marked eye and respiratory tract irritation and chemical pneumonia
400 - 700
½ hr +
Unconsciousness and possibly, death
2
The maximum exposure allowed by OSHA in the workplace over an eight+hour period = 10 PPM. 1000 Immediate Unconsciousness and possibly, death
GENERATION OF HYDROGEN SULPHIDE (H2S) Hydrogen Sulphide can occur in high concentration in the produced fluids from a reservoir. It is possible that a reservoir can start producing H2S at any time particularly where water injection is concerned. H2S may be expected to be generated on installations in the following circumstances: In Storage tanks The production of H2S is most likely if the amount of sea water in storage tanks is high and constant i.e. the same sea water remains in the storage tanks over a prolong period. In untreated water injection systems Deoxygenated sea water is likely to encourage the growth of sulphate reducing bacteria (SRB), and if retention time prior to injection is considerable eg during system shutdown H2S might be produce.
EFFECTS OF HYDROGEN SULPHIDE ON PERSONNEL
When hydrogen sulphide is inhaled by any individual it passes directly through the lungs into the blood stream. If the individual breaths in so much H2S that the body can not oxidize all of it, it builds up in the blood and the individual becomes poisoned. The area of the brain which controls breathing becomes paralyzed, the lungs stop working and the person is asphyxiated. (OSHA regulated H2S permissible levels for unprotected worker as shown in previous slide) The way in which H2S affects an unprotected worker depends on the following; * duration of exposure, * Frequency of exposure * Intensity of exposure * Susceptibility of the worker
THE EFFECTS OF H2S ON EQUIPMENTS H2S is highly corrosive to steel and at high stress levels extreme metal embrittlement may occur in a very short time Due to the extremely damaging effects of H2S, the interior of any vessel which has constant sea water must be properly treated through some chemical biocides. Biocides can damage the cells of the SRB and thus control H2S production
The use of GREEN BIOCIDES is highly recommended as a sustainable approach GREEN BIOCIDES are environment friendly chemicals
Asphyxiant (oxygen deficiency) Risk • We all need to breathe the oxygen (O2) in air to live. • Air is made up of several different gases including oxygen. • Normal ambient air contains an oxygen concentration of 20.9% v/v. • When the oxygen level dips below 19.5% v/v, the air is considered oxygen-deficient. • Oxygen concentrations below 16% v/v are considered unsafe for humans.
2
Asphyxiant (oxygen deficiency) Risk • Oxygen depletion can be caused by: – – – –
Displacement Combustion Oxidation Chemical reaction
• Levels of oxygen below 6% are fatal!
Asphyxiant (oxygen deficiency) Risk 100% v/v O2
20.9% v/v normal
16% v/v depletion
0% v/v O2
6% v/v fatal
Asphyxiant (oxygen deficiency) Risk Air Composition
Symbol
Percent by volume (% v/v)
Nitrogen
N2
78.084
Oxygen
O2
20.9
Argon
Ar
0.9
CO2
0.03
Various
Trace
Name
Carbon Dioxide Neon, Methane, Helium, Krypton, Hydrogen, Xenon
• Air is made up of several different gases including oxygen. • Normal ambient air contains an oxygen concentration of 20.9% v/v. • When the oxygen level dips below 19.5% v/v, the air is considered oxygendeficient. • Oxygen concentrations below 16% v/v are considered unsafe for humans.
Asphyxiant gas limits 100% v/v O2
• • • • 23.0% v/v O2 High alarm 20.9% v/v O2 Ambient 19.0% v/v O2 Low alarm 0% v/v O2
Oxygen, Nitrogen Not flammable or toxic < 6% v/v O2 FATAL > 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<1000hrs/annu m)
(<10hrs/annum)
Europe/IEC
Zone 0
Zone 1
Zone 2
North America (NEC 505)
Zone 0
Zone 1
Zone 2
Area Classification Examples • Zone 0 – Vapour Space in Fixed Roof Tank – Rim Seal of Floating Roof Tank – Open Oil Saver Pit
• Zone 1 – Vents – Drain Trays
• Zone 2 – Leakage due to plant failure or operational error
The Need For Gas Detection
The Need For Gas Detection • Gas detection is mainly used to monitor areas where hazardous levels of gas are not normally present. • They are designed to give early warning of the build up of gas before it becomes a hazard. • Various national and international laws exist that demand the use of gas detection to protect people and plant. • Many local codes of practice also exist that ensure health and safety policies are employed. • Insurance companies will not provide cover to businesses that cannot prove that they have taken appropriate safety measures to detect hazardous gases.
The Need For Gas Detection
The Need For Gas Detection Noxious gas Two victims of a toxic gas leak are helped by paramedics at a hospital in Managua, Nicaragua, on Monday. More than 100 factory workers in Nicaragua were hospitalized after they were poisoned by a gas leak at a textile factory in the capital.
The worst disaster in the history of the chemical industry remains 1984's methyl isocyanate leak in the city of Bhopal, which killed 10,000 people, and maimed or blinded more than 100,000 others.
The Need For Gas Detection Ten Hurt By Toxic Fumes
Toxic gas leak sickens 55 plant workers
City's Water Treatment Plant Closed After Accident.
FIFTY-FIVE workers at a polystyrene factory in Samut Prakan province collapsed and were hospitalised yesterday after inhaling toxic gas reportedly leaked from a nearby factory.
Seven people, including two passers-by, were treated and released from Holland Community Hospital. Dr. Ken Kuper, an emergency room physician at Holland Community Hospital, said mild exposure to chlorine gas is "really quite benign." However, prolonged exposure in a confined space can lead to asphyxiation and death, and direct contact with the mixture can burn the skin.
The Need For Gas Detection A fire was sparked by a pipeline explosion at a Philadelphia Gas Works facility Friday night. (CNN) -- Residents were being asked on Saturday to curb use of natural gas after a dramatic gas pipeline explosion that lit up the Philadelphia night sky late Friday and left some residents without heat.
Typical Areas Requiring Gas Detection
Typical areas that require Gas Detection
Chemical Plants
Boiler Rooms
Power Stations
Hospitals
Water Treatment Plants
Tunnels
TYPICAL PLANT AREAS AND POSIBLE AGT GASES PLANT
TYPICAL AGT GASES
Chemical plant
General hydrocarbons, Hydrogen Sulphide and Ammonia
Water treatment
Methane, Hydrogen Sulphide and Chlorine
Power Station
Natural Gas, Hydrogen, Carbon monoxide, oxygen
Boiler Rooms
Methane, Carbon monoxide
Tunnels
Methane, Hydrogen Sulphide, Carbon Monoxide and oxygen
Laboratories
General hydrocarbons Hydrogen Sulphide and Ammonia
Plants Sumps
Methane Hydrogen Sulphide Carbon dioxide
Process Areas, Pump rows, Compressor station, raw materials storages
General hydrocarbons Hydrogen Sulphide and Ammonia
Principles of Gas Detection And Gas Detectors
Gas Detector • Is a device which can sample the air and detect a variety of contaminant gases, flammable and check for oxygen concentration in a given environment. • Gas detector measures the concentration of a gas(s) and gives an alarm when the gas concentration reaches a preset threshold value. • Gas detectors enable the detection of gases prior to the commencement of an operation, during and after an operation.
Gas Detector • Gas detectors are basically preventive tools- to prevent combustion and inhalation of toxic gases • To prevent combustion, detectors measure the O2 level in relation to the presence of the explosive or combustion gas. (Approximately 16% O2 required for combustion • Measurement looks at the lower explosive limit (LEL); above the LEL the detector bleeps indicating the presence of the set combustible gas(s) • For toxic gas(s), a detector detects the gas it is set to – H2S, CO, Cl2, PH3, etc.
Gas Detectors • There are single gas detectors and multi gas detectors • Similar to gas detectors are gas monitors. • A detector could be fixed or portable • Detectors are very important while working in confined space. It is important to gas test a confined space wearing a B.A. set, prior to commencement of operations.
Fixed Detectors (gas monitors) • A fixed detector is permanently installed in a location to provide continues monitoring of plant and equipment. Often they cover a given range or area. • Fixed gas detectors are used to give early warning signs of leaks from plants containing flammable gases or vapours within the plant. • They are particularly useful where there is possibility of leak into an enclosed space or partially enclosed space where flammable gases could accumulate.
Sample Fixed Gas Monitor
Portable Gas Detector • Portable gas detectors are small handheld devices that could be used for testing atmospheres in confined spaces prior to entry. • Useful for tracing leaks or to give early warning of the presence of flammable gases or vapour when hot work is being carried out in a hazardous area.
Sample Portable Gas Detector
Use of Portable Gas Detectors • Portable Gas detectors could be used actively or passively • Active Use • The operator carries the instrument around while monitoring: The general area The atmosphere within a confined space Checking for leaks from likely sources, e.g. drains or flanges.
Use of Portable Gas Detectors • Passive Use • The instrument is positioned in one place to monitor the atmosphere. Temporarily for a period of hours or days
Note: The operator should switch on the gas detector and note the readings in a gas-free area, before entering a hazardous area.
Other User Guide • For leak seeking or monitoring known leaks or ingress points, the probe should be placed as close to the source as possible with the operator being upwind of the source and as far away as the probe will allow while still being able to monitor the readout. • For testing atmospheres of confined spaces, the sample probe should be positioned inside the space with the operator remaining outside where practicable. The operator should monitor a number of points inside the space, using extended probes where necessary, to take into account vapour pockets and stratification. Note that portable gas detectors are always point detectors. But fixed gas detectors are point or open path detectors.
Point or Open Path Detector Point Detector – These measure the concentration of the gas at the sampling point of the instrument.
Point or Open Path Detector
Open Path Detector – Also known as beam detectors, topically consist of radiation source and a physically separate, remote detector. The detector measures the average conc. of gas along the path of a beam. The unit of measurement is conc. multiplied by path length, %LEL m or PPM m IR Source
IR Detectors
Gas
Open path detectors systems could be designed with path length of 100m or more Draw back – Impossible to differentiate a reading due to a high conc. along a small path of the beam from a low conc. distributed over a longer length.
Infrared Gas Detection IR Source
IR Detectors
Sample & Reference signal strengths
S
R
S
R
S
R
Fog, Rain,Snow,Dirt
Gas
SENSORS • Gas detectors detect gases through sensors. • There are different types, the choice of sensor should be guided by the following: Gas to be detected; Expected range of concentration; Whether detector is fixed or portable; Whether detector is point or open path; Presence of other gases that could affect readings or damage sensor
Types of Sensors
• Flammable gas detectors
Photo ionization useful for both type of instruments Ultrasonic used in fixed instruments. Semiconductor Fame temperature used for fixed instruments Flame ionization mainly fixed but also useful for portable equipment Thermal conductivity mostly fixed but could be used for portable equipment Infrared used in portable and fixed instruments and Catalytic (Pellistor)- fixed and portable instruments
Types of Sensors • Oxygen Detectors
Electrochemical- Used for portable and fixed instrument Paramagnetic – Used in portable instruments Zirconia-type – Used in fixed instruments
Gas Testing Procedure
Gas Testing Procedure • Gas tests shall be carried out to obtain results which are representative of the entire space and the test equipment shall be: – Specific to the gases that have to be tested and sensitive at the TLV – Of an approved type, e.g. intrinsically safe; – properly calibrated and maintained – within its validation period – Checked that is functioning correctly, at the start of each day. • As a general rule, tests shall be carried out in the following sequence: – oxygen content – flammable gas – toxic gas
Gas Testing Procedure • The permit for the work should specify the tests needed and the test frequency. • For both active and passive use, the Gas tester should switch on the gas detector and note readings in a gas-free area, before entering a hazardous area. • Test results should be recorded on the permit for the work or a gas test certificate • If actively testing an area by walking through it, the operator should hold the sample probe in front to determine if it is safe to continue in that direction. • It is advisable to sample at high and low levels, depending on the gas properties and location of the release.
Gas Testing Procedure • When reading the monitor, make sure you avoid trips and falls; hence it is proper to stand still while checking instrument reading • This will also give a more accurate reading for that location as it will take into account the finite response time of the equipment. • For leak seeking or monitoring known leaks or ingress points, the probe should be placed as close to the source as possible with the operator being upwind of the source and as far away as the probe will allow while still being able to monitor the readout.
Gas Testing Procedure • For testing atmosphere of confined space, the sample probe should be positioned inside the space with the operator remaining outside where practicable. The operator should monitor a number of points inside the space accounted vapour pockets and stratification A competent person tests confined space before entry.
Testing for Asphyxiant Qualities • The Oxygen content may be checked with a portable Oxygen analyser to ensure it is not less than 19.5% prior to entry without breathing apparatus • Atmospheres containing less than 19.5% vol. oxygen are considered to be oxygendeficient. • Atmospheres containing more than 21.5 % vol. oxygen should be treated as oxygen enriched.
Flammability Testing • If the concentration of flammable vapors or gases in the space to be entered is equal to or greater than 10 percent of the lower explosive limit, the space shall be labeled "Not Safe for Workers" and "Not Safe for Hot Work • For entry into a confined space without breathing apparatus, the maximum concentration of flammable gases must never exceed 1% LEL.
• Where flammable vapours are present at concentrations greater than 1% LEL but less than 10% LEL, entry is only permitted with breathing apparatus. • Hot Work is not permitted where flammable vapours greater than 1% LEL are detectable anywhere inside the confined space. • Where flammable vapours present exceed 10% LEL, no entry is allowed whether or not breathing apparatus is worn. %LEL (LFL) is a combined measure of the fire/explosion hazard, and of the toxic hazard of general hydrocarbons, when the HRA and JHA establish that there are no specific toxics present.
Toxicity Testing • If a space contains an air concentration of a material, which exceeds permissible exposure limit (PEL) or is IDLH, the space is unsafe for workers entry. • In order to protect workers from possible adverse health effects, OSHA, NIOSH, ACGIH have established PEL for most flammable vapours and gases • However, note that exposure limits are not some magic threshold that define the border between safe and dangerous. A PEL that was acceptable in 1950 may be recognized as dangerously high today. Therefore, always do everything reasonable to limit exposure to chemicals or dusts in the first place.
Permissible Entry Level Parameter
Permissible Entry Level
% O2
19.5% to 23.5%
Lower Explosive Limit
<10%
Carbon Monoxide
+35 PPM
Hydrogen Sulphide
+10 PPM *15 PPM
* STEL – Employee can work in the area up to 15minutes + LTEL – Employee can work in area 8 hrs with*appropriate Aromatic Hydrocarbon +1(longer PPM 5 PPMrespirator)
SOME AGT GASES RELATIVE DENSITY
CH4 CO CO2 H2 S C3H8 C4H10 C2H6 Cl2 H2 O2 N2 He
METHANE CARBON MONOXIDE CARBON DIOXIDE HYDROGEN SULFIDE PROPANE BUTANE ETHANE CHLORINE HYDROGEN OXYGEN NITROGEN HELIUM
0.55 0.97 1.18
1.05
Alarms
• Gas detectors/monitors measure the concentration of gases and give an alarm when the gas concentration reaches a present threshold value. • Sensors send signals to monitor and the monitor automatically sounds alarm at preset concentration. • The alarm should not stop or reset unless deliberate action is taken • The alarm should be audible or visible or preferably both. • Note that it is important for an alarm to warn of fault condition. If a detector fails, it could falsely indicate a safe condition such as allowing a zero reading. Hence it is important that there should be no non – detectable fault conditions in the detector, where possible.
A low battery Alarm • This is usually present on portable instruments • Often the manufacturer‟s instructions should give details of the expected battery life time after charging properly and the operating time left after the low battery alarm is activated. • However, if the low battery indicator does activate, the instrument should be recharged in a safe area, away from the area being monitored, before the detector shuts down.
At What Gas Conc Should the Detector Alarm? • A detector should be set to alarm at a level low enough to ensure the health and safety of people but high enough to prevent false alarm. • False alarm are mostly caused by fluctuations in sensor output, due to: – Environmental changes such as: • Ambient temperature • Pressure and • Humidity and
– Sensitivity to other gases or vapours, sensor drift
• Likely solution would be the use of two detectors- the alarm level must be registered by both detectors before the alarm activates.
Gas detectors must be maintained and operated properly to do the job they are designed to do.
Always follow the guidelines provided by the manufacturer for any gas detection equipment you use!
COSHH The Control of Substances Hazardous to Health Regulations 2002 is a United Kingdom Statutory Instrument that stipulates general requirements on employers to protect employees and other persons from the hazards of substances used at work by risk assessment, control of exposure, health surveillance and incident planning
OSHA & NIOSH The United States Occupational Safety and Health Administration (OSHA) is an agency of the United States Department of Labor. It was created by Congress under the Occupational Safety and Health Act, signed by President Richard M. Nixon, on December 29, 1970. Its mission is to prevent work-related injuries, illnesses, and deaths by issuing and enforcing rules (called standards) for workplace safety and health. The agency is headed by Deputy Assistant Secretary of Labor. The OSH Act, which created OSHA also created the National Institute for Occupational Safety and Health (NIOSH) as a research agency focusing on occupational health and safety. NIOSH, however, is not a part of the U.S. Department of Labor.
USE OF DRAGA X-AM 2000 PRACTICAL TRAINING
COMPONENTS XXS-Sensor H2S
XXSSensor CO
Visual Alarm Horn > 90 db
What is what?
XXS-Sensor O2
OK-button
Visual Alarm
lSwitch on lquit
Catalytic Ex Sensor Front Cover
Crocodile -Clip
Saved Screw
Segment Display
+-button l Navigation
Power pack operating time >12 h
SWITCHING-ON DRÄGER X-AM 1100/1700/2000 SWITCHING ON • Press and hold the “OK”-key for 3 seconds • Display counts down 3-2-1 • Blinking LEDs, the acoustic alarm sounds and the vibrating alarm pulsates • The self-test begins automatically and shows the following: -The installed software version -The expected lifetime (X-am 1100/1700) -The alarm levels -The TWA and STEL alarm settings -The next calibration date
Look at video
SWITCHING OFF DRÄGER X-AM 1100/1700/2000 SWITCHING OFF • • •
Press and hold the “+” and “OK" keys at the same time for more than 3 sec. The LEDs will flash and a long beep will sound. The instrument is switched off
Look at video
DISPLAY ILLUMINATION DISPLAY ILLUMINATION • Press any key and the display illumination is switched on for about 30 sec. • In an alarm situation, the display illumination is automatically switched on
Look at video
MENU FRESH AIR CALIBRATION FRESH AIR CALIBRATION • This procedure is a fresh air calibration, which is placed in the quick menu with help of the CC-Vision Software. • Press “+”-key three times • The following icon is shown • Press the “OK ”-key and choose the fresh air calibration menu • Real values are shown • Press the “OK ”- key • OK appears in the display • Fresh air calibration is finished Look at video
If the oxygen sensor value does not show 20.9% or is not stable, or the combustible or toxic sensors do not show “0” under fresh air conditions, then the instrument must be fresh air calibrated. Perform “Fresh Air Cal” only in a clean air environment.
MENU MAXIMUM VALUE MENU MAXIMUM VALUE •
Press the “OK ”-key once
•
The Maximum Value and the minimum value for the O2 sensor are show. These values have been occured since the last time the instrument was switched on.
•
Press the “OK”- key again. TWA and STEL values appears in the display
•
or press the “+”-key once
•
Instrument returns to measurement mode Look at video
• The Max Value function displays the lowest oxygen reading and the highest Ex, CO, and H2S readings from the time the readings were last reset. Max Values will be stored in memory until they instrument is switched on again.
NOTE
TWA (Time Weighted Average) is the time-weighted average gas concentration (normally over an 8 hour period) that an unprotected worker can be exposed to over an 8 hour workday and 40 hour work week without adverse effects. The STEL (Short Term Exposure Limit) is the maximum allowed gas concentration that an unprotected worker can be exposed within a 15 minutes period.
MENU FUNCTIONS
TWA •
When the TWA analysis is activated:
•
Press the “OK ”-key two times
•
icon appears in the display
•
The maximum workplace concentration is shown
•
Press the “OK”-key again and the STEL values are shown.
•
or press the “+”-key once
•
Instrument returns to measurement Look at video
MENU FUNCTIONS STEL •
When STEL analysis is activated:
•
Press the “OK ”-key three times
•
icon appears in the display
•
The STEL values are shown
•
Press the “OK ”-key or the “+”-key once
•
Instrument returns to measurement
Look at video
A1 GAS CONCENTRATION ALARM A1 GAS CONCENTRATION ALARM •
Alarm level can be changed with the help of the CC-Vision software
•
Audible-, visual- and vibrating alarms repeat periodically
•
The display character “A1” will alternate with the concentration in the display
•
An Ex, CO or H2S alarm, the audible and vibrating alarms can be acknowledged by pushing the “OK
”-key.
Look at video
A2 GAS CONCENTRATION ALARM A2 GAS CONCENTRATION ALARM • Alarm level can be changed with the help of the CC-Vision software • Double audible-, visual- and vibrating alarms repeat periodically •
The display character “A2” will alternate with the concentration in the display
• The audible, visual and vibrating alarms can NOT be acknowledged (silenced) in “A2” or in an O2 “A1” alarm Look at video
Follow the prescribed safety procedures.
STEL ALARM Click the picture to watch video
STEL ALARM • Alarm level can be changed with the help of the CC-Vision software • Audible-, visual- and vibrating alarms repeat periodically • The display character “A2” will alternate with the concentration in the display • Icon flashes • The alarm can NOT be acknowledged
Click the picture to watch video
Look at video
TWA and STEL values will be cancelled when the instrument is switched off. Follow the prescribed safety procedures.
TWA ALARM TWA ALAR • Alarm level can be changed with the help of theM CC-Vision software • Audible-, visual- and vibrating alarms repeat periodically
• The display character “A2” will alternate with the concentration in the display • Icon
flashes
• The alarm can NOT be acknowledged Look at video
TWA and STEL values will be cancelled when the instrument is switched off. Follow the prescribed safety procedures.
A1 LOW BATTERY ALARM Click the picture to watch video
A1 LOW BATTERY ALARM •
Audible-, visual- and vibrating alarms repeat periodically
•
Icon
•
The alarm can be acknowledged with “OK”-key
flashes
Look at video
This is activated when the battery has less than 10 minutes of operation – please change the batteries or charge the instrument.
A2 LOW BATTERY ALARM A2 LOW BATTERY ALARM •
Audible-, visual- and vibrating alarms repeating periodically
•
Icon
•
The instrument will automatically shut down in about 10 seconds
•
Instrument switches off
•
The alarm can NOT be acknowledged
flashes
Look at video
ERROR ALARM ERROR ALARM • Audible-, visual- and vibrating alarms repeat periodically • The icon
appears in the display
• These alarms may be silenced with the “OK” - key, but the gas display will still indicate a fault
Look at video
An error is an indication that something needs to be looked at in the instrument immediately. The instrument should be removed from service and the error corrected before further use
OVER RANGE OVER RANGE • Audible-, visual- and vibrating alarms repeat periodically •
is shown
• The alarm can NOT be acknowledged
Look at video
If the measuring range is exceeded, the following display is shown instead of measured value display. Follow the prescribed safety procedures.
UNDER RANGE UNDER RANGE • Audible-, visual- and vibrating alarms repeat periodically •
is shown
• The alarm can NOT be acknowledged
Video Look at ansehen video
The measured concentration has drifted into the negative range. This can e.g. happen, when the fresh air calibration was done in an area where a concentration of gas was present. Please fresh air calibrate the instrument in a clean environmental.
ERROR DISPLAY ERROR DISPLAY •
Press the “OK ”-key to acknowledge
• •
Press the “OK ”-key again An Error code is shown (Use the instructions to determine what the error code means.)
•
Press the “OK ”-key again. More error code could be shown.
•
Or press “+M”-key to return to measurement Look at video
NOTICE NOTICE • •
Press the “OK ”-key A Notice Code is shown (Use the instructions to determine what the notice code means.)
•
Press the “OK ”-key again. More notice codes could be shown
•
Or press “+M”-key to return to measurement
Look at video
DATA READ OUT DATA READ OUT •
In the display, “PC” appears when the instrument is connected via IR interface to a personal computer
Look at video
FUNCTION TEST • A „Bump Test“ is a function test. Before using the instrument, it is important to check following:
• Gas channels are not blocked (e.g. with dirty membranes ) • The sensors are calibrated correctly • The correct alarms are shown • The alarm levels have been adjusted correctly
AUTOMATIC BUMP TEST AUTOMATIC BUMP TEST • • • • • • • • • •
Slide the instrument into the bump test cradle The Bump Test Station automatically recognizes the instrument Gas is supplied to the sensors The values increase Audible and visible A1/A2 alarms are shown Is the Bump test is correct, “OK” appears in the display The bump test is completed If the bump test is not correct, A channel error “_ _” is shown for the specific sensor The instrument should be calibrated or contact your local service.
MANUAL BUMP TEST MANUAL BUMP TEST • • • • • • • • •
Slide the instrument into the calibration cradle Press “+M”-key three times Manually supply the gas The values increase Audible and visual A1/A2 alarm are shown Press the “OK ”-key The bump test is completed Or a channel error “_ _” is shown for the specific sensor The instrument needs to be calibrated or contact your local service
CHARGING THE BATTERY PACK CHARGING THE BATTERY PACK • Slide the instrument into the charging module • Connect the charging module with a single- or multi-charger • The instrument is charging • Red LED blinks -> 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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