Schools’ Health and Safety Handbook
Section9.3: Code of Practice for Secondary Design and Technology
Risk Assessment HT 06: Oxy-Acetylene Welding and Welding Installations
September 2007
Risk Assessment HT 06: Oxy-Acetylene Welding and
Welding Installations
ESTABLISHMENT
DEPARTMENT
WORK ACTIVITY
HAZARDS
SCHOOLS TEACHING SECONDARY DESIGN AND
TECHNOLOGY
DESIGN AND TECHNOLOGY
OXY-ACETYLENE WELDING AND WELDING
INSTALLATIONS
All users should be aware of the following hazards:
 If damaged or involved in a fire, compressed
oxygen cylinders can explode violently.
 Enrichment of the air caused by oxygen leaks
makes fires burn quicker and more violently.
 The cylinders of acetylene gas can explode
violently if involved in a fire and this would require
evacuation of the surrounding area.
 Acetylene gas leaks can form an explosive mixture
inside buildings if the area is not adequately
ventilated.
 Welding equipment can present the risk of electric
shock.
 Sparks from welding can cause burns to the skin,
eyes and clothes.
 Hot metal components, which have been heated
by welding, can cause burns.
 The chipping or cleaning of welds can lead to eye
injuries.
 Ultraviolet and infrared radiation can cause “arceye”, a painful, but usually temporary eye
condition.
 Welding can present a fire hazard.
 Explosive vapour-air mixtures can form inside
containers that have previously contained
inflammable liquids.
 Hazardous fumes may be produced during the
welding process.
WHO MIGHT BE
HARMED
(EMPLOYEES)
Design and Technology Teachers
Design and Technology Teaching assistants
Design and Technology Technical assistants
WHO MIGHT BE
HARMED
(NONEMPLOYEES)
Pupils and students.
Visitors
Cleaning Contractors,
Maintenance Contractors
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Schools’ Health and Safety Handbook
Section9.3: Code of Practice for Secondary Design and Technology
Risk Assessment HT 06: Oxy-Acetylene Welding and Welding Installations
September 2007
IS ANYONE AT
SPECIAL RISK
GENERAL RISK
CONTOL
MEASURES
Persons working alone
Inexperienced teachers
Persons who have not been trained and certificated
within the past five years.
Persons who use the equipment infrequently
Unauthorised users, for example, site manager,
caretakers
Training and Supervision
 Persons supervising work in welding areas should
be trained to the standard specified in Health and
Safety Training Standards in Design and
Technology (DATA) or should have equivalent
professional qualifications to industry standards.
Welding Areas
 Welding areas must be separated from other work
areas by fixed or portable screens that protect
persons who are not wearing eye protection
goggles.
 Welding areas must be kept free from combustible
materials and flammable liquids.
 A fire extinguisher and fire blanket must be readily
available.
 Welding must not take place directly onto a dense
concrete or non-refractory cement base, as these
materials may disintegrate explosively when
heated.
Ventilation
 There must be a good level of general ventilation
provided when welding is taking place.
 Concentration of welding fumes must be avoided.
 A risk assessment must be carried out for the
welding process and suitable control measures
and local exhaust ventilation must be provided as
required.
Personal Protective Equipment
 People using welding equipment, and people
observing them, must be protected against glare
and sparks by suitable goggles or shields.
 Goggles or shields must also be used when
chipping or cleaning welds.
 When welding suitable protective clothing,
including gloves aprons and substantial footwear
must be worn to minimise risks of spark burns and
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Schools’ Health and Safety Handbook
Section9.3: Code of Practice for Secondary Design and Technology
Risk Assessment HT 06: Oxy-Acetylene Welding and Welding Installations
September 2007

clothing damage.
Protective clothing must be kept free of oil and
grease.
Prohibited Work
 Welding, cutting or any other heat processes must
not be performed on tanks.
 After use, welded materials should be put in a safe
place to cool down in order to minimise the risks
fires or burns.
Maintenance
 Welding equipment must be included in a planned
annual maintenance programme, and this should
include any appropriate electrical safety tests.
 Oxy-acetylene equipment, where date stamped,
should be service-exchanged or replaced every
five years.
 Proprietary leak detecting fluids should be used to
test for leaks from connections
OXY-ACETYLENE
WELDING
Gas Supply
 Gas pipes must be installed by a competent
person, in accordance with the Pressure Systems
Regulations.
Cylinders
 Oxygen and acetylene cylinders should only be
kept in the workshop when they are in use.
 Oxygen and acetylene cylinders must be secured
in an upright position at all times. Usually, they will
be kept on a trolley.
Ventilation
 They must be kept in well ventilated areas away
from all combustible materials.
Warning Signage
 Warning signs reading “Beware Compressed Gas”
and Beware Flammable Material” conforming to
BS 5499-5 and the Safety Signs and Signals
Regulations 1996 should be displayed at
entrances to the workshops.
Storage, Setting-up and Care of Gas Cylinders
 Spare cylinders, whether they are full or empty,
should be kept in a safe, secure and well
ventilated place, having direct access to the
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Schools’ Health and Safety Handbook
Section9.3: Code of Practice for Secondary Design and Technology
Risk Assessment HT 06: Oxy-Acetylene Welding and Welding Installations
September 2007
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outside the building.
The cylinders must not be kept below ground level,
or next to drains, basements or other low-lying
places.
Only those oxygen and acetylene cylinders
currently in use should be kept in the workshop.
Cylinders must always be treated with great care.
They must not be subjected to mechanical
damage, falls or abnormal heat levels.
Cylinders must be kept on trolleys and be secured
upright, so they cannot be knocked over. It is
important that the correct trolley is used to
minimise the risk of them being knocked over.
Acetylene cylinders contained liquid and must be
kept with their valves uppermost at all times.
When carrying out welding the appropriate
regulators, hoses, non-return valves, flame
arresters and torches must be used. Advice on
these items should be obtained from the welding
equipment supplier.
Oil and Grease
 Note: Oil or Grease must not be allowed to come
into contact with oxygen regulator valves or fittings
as this can spontaneously combust.
Lighting-Up, Shutting Down and Working
Procedures
 The risk of a welding flame “flash-back” into hoses
or cylinders must be minimised by training the user
in the correct lighting-up and working procedures,
and by fitting effective non-return valves and flame
arresters.
 Cylinder valves must be turned off after use.
Changing Cylinders
 Cylinders must only be changed in a well
ventilated place, well away from sources of
ignition.
Leak Detection
 Proprietary leak detecting fluids should be used to
test for leaks from connections.
FURTHER ACTION
REQUIRED TO
CONTROL RISK
ACTION BY
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Schools’ Health and Safety Handbook
Section9.3: Code of Practice for Secondary Design and Technology
Risk Assessment HT 06: Oxy-Acetylene Welding and Welding Installations
September 2007
PERSON
ACTION BY DATE
DATE REVISION
OF ASSESSMENT
DUE
ASSESSED BY
DATE
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