Civil Engineering Reference
In-Depth Information
A demolition survey to identify any potential fi re
and explosion risks together with other risks must be
undertaken. This should assist in:
➤
Locating underground services
➤
Identifying whether such services are in use or are
disused
➤
Determining how supplies can be disconnected or
otherwise made safe (usually undertaken by a repre-
sentative of the local supply company)
➤
Identifying the fl ammable and/or explosive concen-
trations that may be contained within any tanks'
structure
➤
Determining methods of residue removal or how the
materials will be made inert.
Any demolition work must be conducted by a compe-
tent company ensuring that all persons involved with the
work have received adequate training, are familiar with
the method statement and operate to a permit to work
system.
The general requirements for provision of fi re
fi ghting equipment must also be considered together
with the provision of gas monitoring systems that can
detect the presence of fl ammable vapours.
Figure 8.30
Tar boiler used to heat bitumen
identifi es that the movement of hot tar presents a greater
risk the following should be provided:
➤
An insulated non-combustible base must be pro-
vided for the tar boiler to be placed upon
8.4.17
Arson and site security
➤
The boiler should be sited in such a way that spilled
material can be easily controlled
➤
Hazardous material (fl ammable substances) must be
removed from within close proximity
The majority of issues relating to arson have been dis-
cussed previously within the chapter; however, the
instances of arson on construction sites are signifi cant,
particularly from unauthorised access, especially by
children.
As secure fencing is required under construction
legislation, arrangements for monitoring the fencing/
hoarding around the site should be included as part of
any control measure.
Secure storage of fl ammable liquids, LPG and any
substantial volume of combustible materials must be
considered, particularly when the site is closed.
On some sites, particularly those vulnerable to
arson, gathering details relating to the area's history is
an essential part of site security.
Precautions that need to be taken may include:
➤
The equipment must be supervised by a competent
supervisor in particular relating to the bitumen level,
temperature and lid securing devices
➤
Gas cylinders should be secured in a vertical posi-
tion, fi tted with a regulator and fl ashback arrestor
and be sited at least 3 metres from the burner
➤
Arrangements to ensure the lit boiler is not left
unattended
➤
Residual materials should be removed prior to sign-
ing off of the hot work permit.
8.4.16 Demolition
All demolition operations fall under the Construction
(Design and Management) Regulations (CDM) and there-
fore require a systematic approach to the operations.
Specifi c details relating to demolition will appear in the
construction phase health and safety plan, the fi re plan,
demolition risk assessments and method statements.
To combat the high risk of fi re and explosion when
undertaking demolition works, e.g. disruption and ignition
of buried gas services or dismantling of tank structures
that may have contained fl ammable residues, a formal
system of work should be adopted.
➤
Signifi cant physical anti-climb fencing/boarding
➤
Security lighting
➤
CCTV monitoring
➤
Regular out of hours security controls or a perman-
ent presence
➤
Liaison with local authorities including the fi re and
police service.
Securing items such as expensive plant and tools away
from view, together with the management of combust-
ible waste (secure skips), also reduces the risk of arson
