In this article we look at why responsibility for breaches in compartmentation need to be driven from the top and backed by comprehensive training to ensure those who commission refurbishments and those who are responsible for carrying out regular inspections understand the importance of fire-rated separating elements.
The purpose of fire-protection measures in a building is to protect people and property, and an important element of this relies on effective fire-stopping in separating elements such as walls and floors. It is these fire-resisting compartments that control the degree and speed of spread. Most buildings are now required to have these ‘compartments’, which can range from fire doors to maintain a safe passage from third-storey living spaces – such as a loft in a residential home – through to multiple compartments in a high-rise building designed to contain fire for a given amount of time, allowing occupants to evacuate to safety.
Despite buildings having these passive fire-protection systems designed in at construction stage, it is still common for compartments to be breached by the addition of mechanical and electrical services that are not correctly fire-stopped. It can also occur whilst the building is being constructed, when gaps around the aperture aren’t adequately fire-stopped, or where it has been installed incorrectly. When this occurs it means that the compartment does not achieve the required degree of containment, allowing the fire to spread quickly to other areas of the building and seriously restrict the time that occupants have to evacuate. Essentially, compartments delay the spread of fire by containing it in one or more rooms or floors, providing more time for occupants to evacuate.
In recent months, and reinforced by the tragic events at Grenfell Tower, there have been calls for building owners of both new and existing structures to check that the fire-stopping of apertures in compartmented walls and floors has been carried out correctly. Unfortunately, many of the buildings have been found to have serious issues with breaches through these compartmental walls and floors. In large multi-residential or commercial buildings, this can result in people relying on the fire being contained within a relatively small area when in reality it will spread rapidly to all areas. The Grenfell tragedy highlighted how quickly fire can spread through a building and although the inquiry still has to publish its findings it is fairly obvious that the fire spread rapidly between ‘compartments’.
As smoke travels quickly – at between 15 and 90 metres per minute – studies have shown that 67% of fire-related deaths are through smoke inhalation and 44% of deaths involve people who were not in the room where the fire originated. Fire separation, if installed correctly, can significantly improve safety for building occupants although breaches through compartment walls, floors and ceilings can cause smoke, gases and fire to spread through to escape routes such as corridors and stairwells. As well as allowing fire spread, it also hinders the fire services’ operations and can put firefighters at increased risk as they enter the building to fight fire.
Building Regulations Approved Document B requires that buildings are subdivided into a number of discrete compartments using construction materials, in order to prevent the passage of fire from one cell to another for a given period of time. Unlike active fire protection, a passive system requires no activation. For example, a fire-rated collar on pipework, which can provide up to 4 hours’ protection, does not need an external stimulus to perform its vital role.
Passive fire-protection systems effectively compartmentalise a building by creating fire-resistant walls and floors, which allow sufficient time for occupants to evacuate – typically with 30, 60, 90 or 120 minute protection. Fire-stopping products used to maintain the integrity of these compartments must be tested to current standards including BS EN1366-3: 2009 and BS476: Part 20: 1987.
An issue arises when a fire compartmentation is breached. As outlined in the Regulatory Reform (Fire Safety) Order, every building should be subject to a fire risk assessment and regular inspection programme of both active and passive fire systems.
As building’s move through their lifecycle, refurbishment work is carried out and mechanical, electrical and IT services may be upgraded, meaning that fire compartments can become compromised through creation of new apertures. This is why it is so important that they are regularly inspected to ensure they have adequate fire-stopping, which retains their integrity and provides the level of protection required. Part B states that “any alteration which at any stage of the work, results in a building being less satisfactory than it was before in relation to compliance with the requirements of Part B…is therefore controlled by Regulation 4 as it is classed as building work.” It is therefore vital that any works do not compromise the integrity of the fire compartmentation, which is why regular inspections should be carried out.
Breaches in compartmentation are often down to a lack of understanding and control over external contractors when carrying out work. That is why construction site managers and property managers need to ensure that any breaches are identified in an appropriate manner. There are serious considerations for site and property managers who do not undertake adequate fire risk assessments.
As a result, fire-safety strategies, in order to be effective, need to be driven from the top of an organisation and backed by comprehensive training to ensure those who commission refurbishments and those who are responsible for carrying out regular inspections, understand fire compartmentation and the implications for breaching this during refurbishment works.
Training may also need to be given to persons carrying out fire risk assessments to ensure there is sufficient knowledge in terms of the location and type of fire compartmentation and fire-stopping system deployed, and its function and the importance of maintaining it to achieve the expected level of fire resistance. A good way to reduce risk is to bring in an external company to take care of fire risk assessments. Failure to do this could lead to seriously increased levels of risk within a building and direct contravention of the Regulatory Reform Order (Fire Safety) 2005. Fire compartmentation should be assessed and reasonable endeavours should be made to at least sample fire-stopping in areas where there is obvious potential for penetration.
The ideal solution is that passive and active fire-protection systems are both in place and subject to regular inspections and maintenance as part of the fire risk assessment. London Fire Brigade (LFB) chiefs have recently warned of “an increased risk of serious building fires unless the construction industry starts to take fire safety more seriously.” The LFB’s experts revealed that all too often they see serious flaws when inspecting buildings. The most common include breached compartmentation, exacerbated with a lack of understanding of what fire-safety measures are in place and how to maintain them.
Compartmentation of buildings was introduced to contain fires and to reduce the risk of it spreading and causing a much larger, more destructive incident. Larger fires are obviously more dangerous to occupants and rescue services as well as those living and working nearby. Compartments also provide more time for people to escape by protecting the integrity of ‘means of escape’ routes such as stairways. In a worrying number of cases, the fire-stopping strategy for service apertures is an afterthought, which is why it needs to be driven from the top. That will ensure guidance is always sought from both the manufacturer and the specialist contractor at the earliest possible opportunity to ensure fire-stopping is carried out effectively. Partnering with an accredited fire-stopping installer that can issue a certified installation will ensure the compartment performs to that set out at design stage, and for the lifetime of the building.
For more information, go to www.quelfire.co.uk
Top image: Fire-stopping around pipes penetrating through plasterboard partitions.