Safe use of Gas Cylinders - ConsultNet.IE

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©Consultnet Limited

Safe Use of
Cylinder Gases

©Consultnet Limited

Presentation Contents

Introduction to Gas Cylinder Safety

Main causes of Accidents

Main Hazards

Rules for Safe Working with Gas Cylinders

Gas Regulators

Flashback Arrestors

Hoses, Piping, Blow Pipes and Torches


unique properties

Handling Gas Cylinders

Transporting Gas Cylinders

Safe Storage

Cylinder Incident Response

Gas Cylinders Hazards in Your Workplace


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Compressed gases used in a variety of industrial and
laboratory situations

Compressed gases present a unique hazard. Depending on
the particular gas, there is a potential for simultaneous
exposure to both mechanical and chemical hazards

Gases can be:

Flammable or combustible






Pyrophoric(burns on contact with air)

or a combination of hazards

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Common Industrial Gases


support combustion e.g. air & oxygen


do not generally react with other materials,
asphyxiants(leak displace air) e.g. nitrogen, argon,


when mixed with oxidant and ignition
source will burn e.g. acetylene, hydrogen, propane


toxic in small concentrations e.g. ammonia,
chlorine, carbon dioxide


react with materials causing reactions
e.g. chlorine, sulfur dioxide


ignite spontaneously in air e.g. silane,

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Main Causes of Accidents

Inadequate training and supervision

Poor installation

Poor maintenance

Faulty equipment and/or design(e.g badly
fitting valves or regulators)

Poor handling

Poor storage

Inadequately ventilated working conditions

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Main Hazards

Impact from the blast of a gas cylinder
explosion or rapid relase of compressed gas

Impact from parts of gas cylinders that fail
or any flying debris

Contact with the released gas or fluid(such
as chlorine)

Fire resulting from the escape of flammable
gas or fluids such as LPG

Impact from falling cylinder

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Safe Working with Gas


Identification and Properties

ead the label

to see what gas you are dealing with

and double
check tha the cylinder/gas is right for th eintended use

No compressed gas cylinder should be accepted for use that
does not legibly identify its contents by name

If the

labeling on a cylinder becomes unclear

or an attached tag
is defaced to the point the contents cannot be identified, the
cylinder should be marked "contents unknown" and

directly to the manufacturer

Never rely on the color of the cylinder

for identification. Color
coding is not reliable because cylinder colors may vary with the
supplier. Additionally, labels on caps have little value because
caps are interchangeable

If there is a mismatch between the color of a cylinder and the
label. Do not use, contact the supplier immediately

now the properties

of the gas (read Material Safety Data Sheets

available from your Supervisor)

The cylinder’s
contents should be identified at all times

as well
as the cylinder status (full, empty or in service)

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Safe Working with Gas


Work Practices

Securely restrain
cylinders to prevent them falling over

Close the cylinder valve
and replace dust caps when cylinder not in use

Before connecting a gas cylinder to equipment or pipework

make sure regulator and
pipework are suitable
for the gas and pressure being used

Never drop
a gas cylinder

ever tamper

with cylinders or subject them to abnormal mechanical shocks which
could damage the valve or safety device

paint, change markings or identification or interfere with threads

disguise damage to a cylinder or valve. Label as faulty and contact the supplier

attempt to repair a cylinder


scrap a cylinder


subject cylinders to abnormally high or low temperatures


mix gases in a cylinder


try refill a cylinder


transport by rolling them on the ground or use them as rollers or supports


pick them up by magnetic lifting


subject to abnormal mechanical shocks whuch could damage the valve or safety

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Safe Working with Gas


Daily Inspection

Cylinders should be inspected daily
and prior to each use for corrosion,
leaks, cracks, etc.

Inspection should include the
cylinder, piping, safety relief
devices, valves, protection caps and

Leaking regulators, cylinder valves
or other equipment should be taken
out of service.

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Safe Working with Gas


Maintenance of cylinders and their valves or relief devices shall be
performed only by trained personnel.

An emergency response plan shall be developed and implemented
wherever compressed gas cylinders are used, handled or stored.

Never smoke around compressed gas cylinders.

Valve protection caps must remain in place at all times except when
cylinders are secured and connected to dispensing equipment

Only wrenches or tools provided by the cylinder supplier should be
used to open or close a valve. At no time should pliers be used to
open a cylinder valve.

Never apply PTFE tape, jointing compounds or any other sealing
material to the valve in an attempt to achieve a tight seal, if a gas
tight seal cannot be achieved metal to metal, replace the regulator or
change the cylinder

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After the regulator is attached, the cylinder
valve should be opened just enough to
indicate pressure on the regulator gauge (no
more than one full turn) and all the
connections checked with a soap solution for

Never use oil or grease on the regulator of a
cylinder valve.

Before a regulator is removed from a cylinder, the cylinder valve shall

be closed and the regulator relieved of gas pressure.
The valve

cap shall be replaced, the cylinder clearly marked as "empty,"

and returned to a storage area for pickup by the supplier

Regulators, gauges, hoses and other apparatus shall not be used on

gas cylinders having different chemical properties

Valve outlet thread size is different for different products but the

same products from different gas suppliers will have the same


Gas Cylinder Use

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Gas Cylinder Regulators

A regulator is a device that receives gas at a high
pressure and reduces it to a much lower working

recision instruments and MUST be handled with care
to avoid damage to their sensitive springs, diaphragms,
valve seals etc.

quipment should display the relevant
European/British Standard number and the pressures
up to which it can operate

eave the pressure adjustment knob/screw fully out
when the regulator is not in use (this ensures a
minimum of tension on the springs and diaphragms)

Cylinders should be placed with the valve accessible at
all times. The main cylinder valve should be closed as
soon as it is no longer necessary that it be open, it
should never be left open when the equipment is
unattended or not operating

This is necessary not only for safety when the cylinder is
under pressure, but also to prevent the corrosion and
contamination resulting from diffusion of air and
moisture into the cylinder after it has been emptied.

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Flashback Arrestors

Flashback is the result of mixture of fuel gas and oxygen
burning within the hose, flame travels and burns its way
towards the gas source at great speed, can result in force of
explosion in either cylinder

Flashback arrestors must be fitted on both oxygen and fuel
gas regulators

If flashback arrestor is dropped/damaged replace

Flashback arrestors should oinly be used with the gas they
are labelled for and the presuure thay are designed for

Coomon reasons for flashback: incorrect purging of
hose/torch prior to use, incorrect gas pressure, incorrect
nozzle, damaged torch valves, gas passages blocked within
the torch, kinked or trapped hose

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Correct hose bore size, pressure rating, length and color coding are essential
for safety BS EN 559


oxygen, Red

acetylene and other fuel gases(except LPG)


inert and non combustible gases


Liquified Petroleum Gas

Never use hoses that are longer than necessary

Never use equipment while hoses are wrapped around the cylinders or trolley

Length of hose should be suitable for the task

Keep hoses in good condition

Examine the hose for cracks, deterioration, damage and test the hose for
leaks before use

Do not repair hoses unless you have the skill and means to test hem in
accordance with BS En 1256

Purge hose thoroughly before lighting torch

o not put wrapping tape around hosing as this contains combustible

o not use copper piping with acetylene hoses as it is potentially explosive

rotect hosing from heat, oil, grease or mechanical damage

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Distribution lines and their outlets should be
clearly labeled as to the type of gas contained

Piping systems should be inspected for leaks on a
regular basis

Special attention should be given to fittings as well
as possible cracks that may have developed

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Blow Pipes and Torches

Leaks are a serious hazard as they are closest to the operator

Always check condition before use, ensure tip is free of obstruction

Signs of heat damage around the blow pipe or torch may indicate the equipemnt
has sufferd interal damage and is leaking and should be replaced immeidately

No sign of sideways movement of the cutting leaver as this could cause gas
leaks within the body of the torch that are difficult to detect

Always fit the correct size nozzle for the job( hole size and pressure set at
regulator determine gas flow and gas velocity exiting the nozzle, manufacturer
gives a pressure rating for the nozzle being use, if the gas exit velocity is slower
than the combustion velocity backfire and flashback may occur

Replace blow pipe or torch if

Broken bent or loose gas control valve

Bent mixer, misshapen cutter head

Bent cutter tube

Broken of bent cutting oxygen lever

Leak test all connections and valves prior to use

If replacing O ring seals always use the correct materials

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Unique properties

Acetylene gas under excess pressure becomes

Cylinders should never be subject to intense heat
or physical impact as the rise in temperature and
pressure may cause the acetylene to thermally

Prior to moving a cylinder that has been subject to
heat or severe impact contact trained emergency
personnel who can check for temperature rise and
apply correct procedures

The cylinder may appear normal but if it is moved
it may detonate with fatal consequences

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Handling Gas Cylinders

Wear PPE: gloves, protective footwear, eye protection

Correct way to move cylinders is to:
keep upright, secure and with
valves uppermost

Use mechanical aids such as a trolley where reasonably practicable(
do a risk assessment)

Use suitable cradles, slings, clamps or other effective means when
lifting with a hoist or crane

or short distances on even ground the practice of ‘milk

(manually moving cylindres)

can be used
by trained personnel

and never
for longer distances,
uneven ground
wet or icy
, poor lighting, or at speed

a trolley should be used

All personnel involved should have completed manual handling

Never roll cylinders along the ground

Never transport cylinder with valve and pressure regulator attached
or with the valve open

ever attempt to catch a falling cylinder just get out of the way

Never lift a cylinder by its cap, valve or guard/shroud

emember that a cylinder is never empty

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Carriage of Dangerous Goods Regulations apply

f possible carry in open vehicles or trailers

f they must be carried in closed vans/cars ensure good
ventilation at all times

f the load compartment is not separated from the driver
do not carry toxic gas cylinders (those with a toxic gas
label and having yellow as a colour on the cylinder)

ecure cylinders properly so they cannot move

or fall

transit or do not project beyond the edges of the vehicle
normally in the upright position unless instructions for
transport state otherwise

Ensure gas cylinders are clearly labelled to show contents
and associated hazards

Fit suitable protective valve caps and covers to cylinders

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Carriage of Dangerous Goods Regulations apply

Disconnect hoses and regulators from cylinders

arry propane cylinders upright and do not
carry flammable gas cylinders in the same
compartment as toxic gas cylinders

o not smoke while carrying cylinders inside

nload the cylinders as soon as possible and
move to a well ventilated storage area

f you suspect it is leaking

park the vehicle,
investigate the fault and contact the supplier

f you are involved in an accident advise

emergency services involved what gas cylinders
are being carried

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Safe Storage

Each Storage area should be subject to unique risk assessment

t is best to store gas cylinders in the open and on concrete in a fenced
compound with some weather protection


storage areas oxygen cylinders must be stored at least 3 metres
away/separated by a fire wall from fuel gases
such as

propane, methane etc.

ull cylinders should be stored separately from empties and empty
oxygen cylinders should be segregated from empty fuel gas cylinders

ther products should not be stored in the gas storage areas
especially not oil or corrosive liquids
, sources of ignition or flammable

Ease of access into and around storage area, such as provision of aisle
>0.6m to prevent domino effect

LPG cylinders have special requirements including storage 3m away
from other gases

Pyrophoric and toxic gases should be stored seperately in locked,
suitable ventilated storage areas with restricted access

Protect gas cylinders from external heat sources which may adversely
affect their mechanical integrity

Cylinders should be secured and properly restrained,
secure with
straps or chains connected to a wall bracket or other fixed surface, or
by use of a cylinder stand

Cylinders should be clearly labelled to show contents and associated

©Consultnet Limited


tore all cylinders upright and secure
on a level surface
prevent them from falling

cetylene and propane must never be stacked horizontally
either in storage or in use

torage arrangements should ensure turnaround of stock in
adequate time

torage areas with gas cylinders must have more than one exit

ylinders should be located away from any heat/source of
ignition and if possible away from the fire exit
walkways, building egresses, unprotected platform edges, or in
locations where heavy moving objects may strike or fall on them

Storage arrangements should be clearly described in the
emergency plan

Storage area must have good housekeeping and adequate
warning signs with fire fighting equipment as necessary

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Incident Response

Report any damaged/leaking cylinder to supplier

f a cylinder


but the leak
has not ignited

and it
is safe to do


having considered the gases specific

liminate all sources of ignition

nsure the valve is closed but do not over
tighten it

ut the cylinder in a safe place that is well

keep it upright

ark the cylinder as faulty and not to be used

arn everyone in the area of the gas leak

nform the supplier

nsure the work area is thoroughly ventilated before
continuing with any work

If a hydrogen cylinder is involved be aware that
hydrogen burns with an invisible flame so seek expert

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Incident Response

Report any damaged/leaking cylinder to supplier

If a
cylinder is leaking and it has ignited

it could

the emergency services
and evacuate the
area to a minimum distance of 100 metres

Where a
cylinder has been damaged

f it has been dropped or physically damaged check it
for leakage and deal with as for a leaking cylinder

or handling acetylene cylinders
should not be moved
unless it is clearly established that there is no
thermal disassociation

learly mark any cylinder that has been exposed to
excessive heat or physical impact and contact the

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Incident Response

If a
flashback has occurred

Close both blowpipe valves oxygen first

Close both cylinder valves

Check the temperature of the acetylene cylinder for
thermal decomposition

Check the blowpipe has not overheated

Check the nozzle is not damaged

Open both blowpipe valves oxygen first to vent the

Unwind the pressure adjustment screw on each
pressure regulator

Before starting up again, check the integrity of the
whole system

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Incident Response

Gas Cylinders on Fire

Depends on the gas, whether the gas is alight at the cylinder
valve or if the cylinder has been subject to severe pressure as
a result of the heat from the fire. Nature of hazard will
determine procedure to be applied

If cylinder has been involved in fire do not approach, evacuate
the area to 100m minimium to 300m

Call fire brigade

Use large quantities of water to cool the cylinders if safe to do so
(do not aim high pressure water direct at the cylinders) from a
safe location and await the arrival of trained emergency
personnel (
Emergency plan training should address

Remove any cylinders not involved in fire to safe place, ensure
valves are closed if safe to do so

Inform gas supplier,

If cylinder contents are unknown, treat as acetylene

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In Your Workplace

Look Out for Gas Cylinders:

In horizontol position/on the ground

In contact with electrical cords

Not protected from falling

chain not secure


In an area where could be subject to impact such
as near operating forklift

Stored near combustibles

Oxygen and acetylene stored together

Without valve caps

Deal with these Hazards IMMEDIATELY

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Compressed gases present a unique hazard. Depending on
the particular gas, there is a potential for simultaneous
exposure to both mechanical and chemical hazards

Inadequate training and supervision, poor installation, poor
maintenance, faulty equipment and/or design(e.g badly
fitting valves or regulators), poor handling, poor storage,
inadequately ventilated working conditions

When working with compressed gases you need to know the
properties of the gas, safe use procedures and what to do
when things go wrong

For detailed use of individual gases you should now review
the relevant Material Safety data Sheet (MSDS) for each gas
used on your site

Always Treat Gas Cylinders with Respect

For additional information which could be used as presentation handouts visit
HSE information on
Gas Safety

a whole series of leaflets on the topic