Firestop and fire protection

Fire protection involves many different measures, with the most visible being fire extinguishers, alarms and sprinkler systems. These are known as 'active' fire protection measures - their job is to detect the threat of fire, and hopefully put it out before the situation becomes more serious. In an ideal world, this would be enough but system failures or other complications can render active measures ineffective.

Alongside the active fire protection systems, passive fire protection systems are used to contain and limit the spread of fire. These are in the form of fire resistant sealants and intumescent products installed in and around services. Active and passive firestop systems work together - neither can be relied on alone to contain or limit the spread of fire.

What is passive fire protection?

Passive fire protection systems are designed to contain flames in certain parts of a building. This prevents the spread of flames from room to room and floor to floor. Just as importantly, passive protection stops smoke and other toxins from spreading throughout the building, which can be just as damaging as fire. Despite the name passive, these systems are always there and always ready, being built into the very structure and fixtures of a building.

The basic way that passive fire protection systems work is by eliminating gaps and installing firestops at any locations where fire might be able to spread or cause significant damage. This could be a design decision (e.g. not using flammable materials such as wood in certain areas), or the installation of a specific piece of equipment that seals a gap.

In an interview with Buildings, Chris Jelenewicz, engineering program manager at Society of Fire Protection Engineers (SFPE) outlined four key areas to consider with a passive system:

1.    Structural fire protection: Protects key structural components such as steel and joint systems. It is typically achieved by fireproofing with a substance that is flame retardant, such as concrete.

2.    Compartmentalisation: Barriers that prevent the spread of flames. These partitions can include everything from fire-rated walls through to dedicated smoke and flame barriers.

3.    Opening protection: Apertures such as doors, windows or air ducts that can compromise a fire barrier need to be strong enough to withstand flames. For example, special glazing on any pieces of glass.

4.    Firestopping: Perhaps the greatest risk in terms of a fire spreading is small flaws, or penetrations in a fire barrier. These may have been left by a contractor such as an electrician or plumber, and if not protected with a passive firestop product, these gaps can undermine the entire system.

Do I need passive fire protection?

In a word, yes. Passive fire protection is a legal requirement. Aside from making sure that every building has them, owners are responsible for maintaining systems and carrying out routine inspections to ensure quality.

Passive fire protection acts as a safety net, keeping people inside a structure safe in the event of a fire. It's always preferable to identify the threat quickly and put it out with an active fire solution, but you'll sleep far easier knowing that there is another line of defence if first responses fail.

Assuming you are unable to put out the fire, you'll want to know that it isn't going to spread throughout the entire building. In turn, this means that escape routes will be protected for evacuation, far reducing the potential impacts of the fire. In addition, containing a fire makes it far less likely that there will be any structural damage. 

Firestop measures for an effective passive fire protection system

The secret to designing an effective passive fire protection system is in the details. Even if you've used the very best materials and eliminated all obvious gaps between compartments, a small penetration can still represent a major flaw. For example, a pipe that passes through a fire barrier requires a hole to be bored, and if this isn't equipped with an appropriate firestop mechanism, flames will still be able to spread. It is very important to identify where these gaps are likely to occur early in the design phase. 

Another important consideration is the specific installation requirements of some passive firestop mechanisms in order to ensure they will function correctly. If sufficient planning for installation is not done, it can make it very difficult to correctly firestop some types of services. Good collaboration is required between the builder and the services trades during construction, to help the installation of passive fire protection run smoothly.

Considering the huge risk of fire spreading from room to room or floor to floor of a building, firestop mechanisms need to be thoroughly tested and designed to the highest standards. Here at Hilti, all of our firestopping solutions are tested to AS, NZ and EN standards, ensuring that they are up to par with the very latest international best practices. The solutions are easy to install, and simple to inspect when needed. There are all sorts of different firestopping measures available, catering to the unique needs of each specialist on a project. For example, the considerations of an architect will be wildly different to an on-site contractor, but here at Hilti we supply a wide range of passive fire protection solutions for every trade on the construction site.