Speaking at the High Rise Construction Fire Safety Conference held alongside FIREX in London, Mark Cooper, London Region SHE Manager at Wates Construction, outlined some of the new provisions in the latest editions of two principal guidance documents on fire safety for construction sites.
Fire Safety in Construction (HSG 168) and Fire Prevention on Construction Sites (The Joint Code of Practice on the Protection from Fire of Construction Sites and Buildings Undergoing Renovation) are two of the principal guides on construction site fire safety in the UK.
The third edition of HSG 168 tidies up provisions in previous versions and takes account of new technologies and new hazards. Its introduction contains a new definition of a complex site and clarifies the relationship between fire safety and all duty holders under CDM (Construction Design and Management) regulations, explained Cooper.
Fire Safety in Construction, 3rd Edition, from the Health & Safety Executive (HSE)
The addition of Figure 1 to the document describes the five steps of a fire risk assessment, which are to:
Step 2 above introduces the requirement of identifying people at greater risk, such as those wearing PPE (which may affect their ability to hear any alarm or warning), those with health conditions, and those from different cultures.
New provisions for neighbouring properties have been introduced, including the emergency plan needing to identify hazards or vulnerabilities at neighbouring properties, such as petrol stations or schools.
In the case of timber frame buildings and engineered wood products, the risk assessment must consider fire spread and the risk to people beyond the site boundary.
In reviewing the risk assessment, Step 5 includes a new risk assessment checklist which, Cooper said, is a “good practical tool to be used”.
This includes guidance on reducing ignition sources. For example, where smoking facilities are provided, there has to be a fire point in the immediate vicinity. Another updated provision is for hot works, by which:
On reducing potential fuel sources, there’s a new section on modern batteries and fuel types, which discusses the use of hydrogen gas and Lithium-ion batteries. There’s also a new section on precautions to be taken for Bitumen boilers.
With other fuel sources, “Acetylene” is replaced with “Precautions for Oxy-fuel Cutting” and includes new sections on safety precautions for oxy-fuel gas cylinders and safety precautions for acetylene cylinders.
This now includes fire detection. There’s also more clarification on means of escape, with the addition that no flammable or combustible materials should be temporarily or permanently stored in any means of escape, and an additional requirement to test emergency lighting after new components have been added.
Where fire alarms are provided, they need to be properly managed so they do not cause false alarms. It is not acceptable to cover or deactivate smoke detectors where work generates dust – instead, dust should be minimised or extracted. A fire alarm system must be tested by a competent person after installation and when expanded.
There’s a new section on composite building panels which calls for care to be taken to avoid poor joint detailing and inadequate support, which can lead to exposed combustible material that is vulnerable to fire. In addition, sources of ignition during the removal and installation of composite panels should be eliminated, explained Cooper.
The sections on timber frame buildings and engineered wood products have been updated to correspond with the Structural Timber Association’s 16 Steps to Fire Safety and Design Guide During Construction to Separating Distances for Timber Frame Buildings.
It’s become more common for completed floors of new high-rise buildings to become occupied during construction of other floors, or for floors in existing buildings to be refurbished while the remaining floors are occupied.
Clients must make it clear at the design stage if partial occupation during construction is being considered, so that appropriate fire protection is planned. The fire protection must address how fire in occupied parts might affect construction workers and vice versa.
These provisions have been updated to correspond with the Fire Safety Act 2021, which makes changes to the Fire Safety Order 2005 on the definition of external walls, with items fixed to walls such as scaffolding forming part of the premises.
Under the Fire Safety (England) Regulations 2022, CDM duty holders must co-ordinate and co-operate on fire safety precautions with the responsible person(s) while construction work is taking place on an occupied high rise residential building.
Summarising significant changes in the latest version of Fire Prevention on Construction Sites (the Joint Code of Practice v.10), Cooper said one of the changes provides for consideration of the impacts of fire loading from insulation products and temporary materials, including the removal of existing (combustible) cladding and how and where it is stored and disposed of (for example, it can’t be stored overnight).
A new section requires the implementation of “impairment management arrangements” for fire systems if they are removed or disconnected. If systems are out of action, the area must still be covered and supported by a risk assessment undertaken by a competent person. The arrangements should, as a minimum:
Other updates include guidance relating to:
Turning to hot works, the new guidance prohibits the use of “blanket” hot works permits. All hot work should be carried out by trained personnel, with hot work permits having to cover specific times and locations. Updated provisions on the type and size of portable fire extinguishers are also made.
New guidance on the fire watch of hot works that have the potential for widespread impacts has been made, where the continuous fire watch should be maintained for at least an hour after completion of the hot works. Additional checks must be made at regular intervals for a further hour, but may be needed for longer based on a risk assessment.
Similar to HSG 168, there are new provisions on the storage of combustible cladding/facades and combustible insulation. They should be removed away from the building as they are dismantled, stored in a secure closed skip outside working hours, and removed from site at frequent intervals – ideally daily. They must not be stored on scaffolding, roofs or inside the building, for example.
A completely new section on the fire risks posed by electric vehicles has been added. Storage of electric vehicles is prohibited in buildings under construction. If this can’t be avoided, essential electric vehicles must be stored in a minimum 60-minute fire rated compartment, with addressable fire detection, subject to a written fire assessment and provision of appropriate ventilation and fire suppression systems.
Among new provisions for high rise construction sites, there is an amendment to stipulate that the fire resistance of temporary firestopping materials includes both integrity and insulation to 60 minutes’ fire resistance.
“There are many updates to both documents, including major changes to hot work,” said Cooper. “But these are the headlines only – the devil is in the detail,” he concluded.
Documents in full:
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