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Authorised Gas Tester Competence Training Package
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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
2/25/2011 6
• 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?
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
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.
Conduct gas tests when required
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.
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 #4
Obtain authorisation before entering a confined space
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
2/25/2011 14
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?
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. 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
There are three main types of gas hazards
Flammable Risk
• Fire Triangle
Three factors are always
needed to cause
combustion:
1. A source of ignition
2. Oxygen/Air
3. Fuel in the form of a gas
or vapourFuel
FIRE
Flammable Risk
• Each gas / air mixture
is ignitable over it‟s
flammable range
L.E.L. (lower
explosive limit)
U.E.L. (upper
explosive limit)
0% v/v gas
100% v/v air
too lean
flammable
range
too rich
100% v/v gas
0% v/v air
Only Gas, No Air
UEL
Ideal mixture
LEL
Only Air, No Gas
Power of explosion
Flammable Risk
Stoichiometric Point
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 LIMITUEL: 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)
Is the point in the ideal mixture range where we have the best mixture of fuel/gas and oxygen for a complete combustion
Stoichiometric point
% 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 Flash Point OC Ignition Temp. OC
Methane <-20 595
Kerosene 38 210
Bitumen 270 310
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
(.
• Others are completely
odourless like Carbon
Monoxide (CO).
Hydrogen sulphide H2S
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 MonoxidePPM 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. Unconscious within 2 hours. Death within 2-3 hours.
1600 20 minutes Headache, dizziness and nausea. Death within 1 hour.
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
12,800 1-3 min Death
2
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
1000 + Immediate Unconsciousness and possibly, death
The maximum exposure allowed by OSHA in the workplace over an eight hour period = 10 PPM.
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
2
• 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.
Asphyxiant (oxygen deficiency)
Risk
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)
Risk100% v/v O2
0% v/v O2
20.9% v/v
normal
16% v/v
depletion
6% v/v fatal
Asphyxiant (oxygen deficiency) Risk
• 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.
Name Symbol
Percent by
volume (%
v/v)
Nitrogen N2 78.084
Oxygen O2 20.9
Argon Ar 0.9
Carbon
DioxideCO2 0.03
Neon,
Methane,
Helium,
Krypton,
Hydrogen,
Xenon
Various Trace
Air Composition
Asphyxiant gas limits
• Oxygen, Nitrogen
• Not flammable or toxic
• < 6% v/v O2 FATAL
• > ambient changes flammable limits
• O2 depletion caused by:
– Displacement
– Combustion
– Oxidation
– Chemical reaction0% v/v O2
19.0% v/v O2 Low alarm
20.9% v/v O2 Ambient
100% v/v O2
23.0% v/v O2 High alarm
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
• Helps determine sensor placement
• The density of a gas / vapour is compared with airwhen air = 1.0
• Vapour density < 1.0 will rise
• Vapour density > 1.0 will fall
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.
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
Continuous
hazard
(>1000hrs/annum)
Intermittent
hazard (>10<1000hrs/annu
m)
Possible
hazard (<10hrs/annum)
Europe/IEC Zone 0 Zone 1 Zone 2
North America
(NEC 505)Zone 0 Zone 1 Zone 2
•Two main systems are used:
–Europe / IEC
–North America (NEC 505 / 500)
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 DetectionNoxious 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 disasterin 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
Toxic gas leak sickens
55 plant workers
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.
Ten Hurt By Toxic
Fumes
City's Water Treatment Plant
Closed After Accident.
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 Power Stations Water Treatment Plants
Boiler Rooms Hospitals 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 DetectorOpen 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
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.
Gas
IR
Source
IR
Detectors
Infrared Gas Detection
S R
S R
S R
Fog, Rain,Snow,Dirt
Sample & Reference
signal strengthsIR
Source
IR
Detectors
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 shallbe:
– Specific to the gases that have to be tested andsensitive 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 ofeach 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
• Atmospheres containing less
than 19.5% vol. oxygen are
considered to be oxygen-
deficient.
• Atmospheres containing
more than 21.5 % vol. oxygen
should be treated as oxygen
enriched.
• 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
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
Aromatic Hydrocarbon +1 PPM * 5 PPM
* STEL – Employee can work in the area up to 15minutes
+ LTEL – Employee can work in area 8 hrs (longer with appropriate respirator)
SOME AGT GASES
RELATIVE DENSITY
CH4 METHANE 0.55
CO CARBON MONOXIDE 0.97
CO2 CARBON DIOXIDE
H2S HYDROGEN SULFIDE 1.18
C3H8 PROPANE
C4H10 BUTANE
C2H6 ETHANE 1.05
Cl2 CHLORINE
H2 HYDROGEN
O2 OXYGEN
N2 NITROGEN
He HELIUM
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!
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
COSHH
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.
OSHA & NIOSH
USE OF DRAGA X-AM 2000 PRACTICAL
TRAINING
COMPONENTS
+-buttonl Navigation
OK-button
lSwitch on
lquit
Segment Display
Catalytic Ex
Sensor
Horn
> 90 db
Front Cover
Power pack operating time >12 h
XXS-
Sensor CO
XXS-Sensor
H2S
XXS-Sensor
O2
Visual
Alarm
Visual
Alarm
Crocodile
-Clip
What is what?
Saved
Screw
SWITCHING-ON DRÄGER X-AM 1100/1700/2000
•Press and hold the “OK”-key for 3 seconds•Display counts down 3-2-1•Blinking LEDs, the acoustic alarm sounds andthe vibrating alarm pulsates
•The self-test begins automatically and showsthe 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
SWITCHING ON
Look at video
SWITCHING OFF DRÄGER X-AM 1100/1700/2000
• Press and hold the “+” and “OK" keysat the same time for more than 3 sec.
• The LEDs will flash and a long beep will sound.
• The instrument is switched off
SWITCHING OFF
Look at video
• 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
DISPLAY ILLUMINATION
DISPLAY ILLUMINATION
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
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.
Look at video
MENU MAXIMUM VALUE
MENU MAXIMUM VALUE
• 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.
• 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
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.
NOTE
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
MENU FUNCTIONS
Look at video
MENU FUNCTIONS
• 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
STEL
Look at video
• Alarm level can be changed with the help
of the CC-Vision software
A1 GAS CONCENTRATION ALARM
A1 GAS CONCENTRATION ALARM
• 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
• 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
A2 GAS CONCENTRATION ALARM
Follow the prescribed safety procedures.
A2 GAS CONCENTRATION ALARM
Look at video
TWA and STEL values will be cancelled when the instrument is switched off. Follow the prescribed safety procedures.
STEL ALARM
Click the picture to watch video
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
Look at video
TWA and STEL values will be cancelled when the instrument is switched off. Follow the prescribed safety procedures.
TWA
ALAR
M• 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
TWA ALARM
Look at video
A1 LOW BATTERY ALARM
Click the picture to watch video
This is activated when the battery has less than 10 minutes of operation – please change the batteries or charge the instrument.
A1 LOW BATTERY ALARM
• Audible-, visual- and vibrating alarms
repeat periodically
• Icon flashes
• The alarm can be acknowledged
with “OK”-key
Look at video
A2 LOW BATTERY ALARM
A2 LOW BATTERY ALARM
• Audible-, visual- and vibrating alarms
repeating periodically
• Icon flashes
• The instrument will automatically shut down
in about 10 seconds
• Instrument switches off
• The alarm can NOT be acknowledged
Look at video
ERROR ALARM
ERROR ALARM
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
• 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
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
• Audible-, visual- and vibrating alarms
repeat periodically
• is shown
• The alarm can NOT be acknowledged
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.
UNDER RANGE
Video ansehenLook at video
• 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
ERROR DISPLAY
ERROR DISPLAY
Look at video
• 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
NOTICE
NOTICE
Look at video
DATA READ OUT
DATA READ OUT
Look at video
• In the display, “PC” appears when the
instrument is connected via IR interface
to a personal computer
• 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
FUNCTION TEST
AUTOMATIC BUMP TEST
AUTOMATIC BUMP TEST
• Slide the instrument into the bump test cradle
• The Bump Test Station automatically recog-
nizes 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
• 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
MANUAL BUMP TEST
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..
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
CHARGING THE BATTERY PACK
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.
• 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
POWER SUPPLY
BATTERY CASE
OVERVIEW OF THE ICONS
Error Icon
Notice Icon
Fresh Air Calibration Icon
PEAK / Maximum Value Icon
TWA Value Icon
Bump Test Icon
1-Button-Calibration Icon
Span Calibration Icon
Password-Protected Menu
Battery Icon
STEL Value Icon
Special symbols provide a quick message about the instrument status
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
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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.
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.
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[II] Atmosphere Supplying Respirators
Full Mask (B) SCBA(A) SAR
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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
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• 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
When must a respirator be used?
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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.
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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
• Closed Circuit• Breathing apparatus
type to which the exhaled air is re-circulated. 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
• 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
The Face Mask
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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. Full content
2. Work duration
3. 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.
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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.
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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;
-• 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
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
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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 non-routine 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 assistingthe entrant in exiting the confined space, and calling foremergency assistance when required.
CONFINED SPACE ENTRY
Definitions/ Key persons involved in CSE activities
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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;
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Examples of Confined Spaces:
• Tanks
• Manholes
• Boilers
• Furnaces
• Sewers
• Silos
• Hoppers
• Vaults
• Pipes
• Trenches
• Tunnels
• Ducts
• Bins
• Pits
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CONFINED SPACE ENTRY
CSE Hazards. What are the dangers expected from CSE?
1. Oxygen Deficiency. Normal 2. Oxygen Enrichment.( O2 > 21.5%)3. Fire explosion4. Presence of Toxic gases or fumes5. Residues left in the space (process materials)6. Physical Hazards7. 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 issues11. Biological hazards
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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.
CONFINED SPACE ENTRY
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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
planningC. If entry is unavoidable, follow a system of work e.g.
PTWD. 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 entry3. Checking size of entry 4. Ventilation5. Testing of air (Gas testing/ Monitoring)
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CONFINED SPACE ENTRY
CSE CONTROLS
6. Provision of special tools and lighting.7. Provision of BA8. Emergency planning (Prepared rescue plan, Rescue harness, Communication, checking how alarm is raised, first Aid, rescuers etc)9. A valid PTW for the work10. Shut down11. Control of Ignition Sources12. Control of radiation Sources13. Control of Internal Combustion Engines and
Cylinders14. 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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A means must be providedfor both safe normal entryor exit , and emergencyextrication.
Tripods with hoist, lifeline, and full body harness are often used for emergency extrication.
Ladders may be used for ordinary entry and exit.
CONFINED SPACE ENTRY
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RESCUE PLAN