Fire Rating Glossary of Terms
Whilst it is becoming more and more common practice to install Fire rating solutions to new and existing structures, there is still some confusion regarding the products, methodologies and terms used by those familiar to the field. We have compiled - and will continue to - a glossary of terms which are used within the industry to help you understand what different products, codes and terms mean.
| Term | Definition |
|---|
| Ablative |
In Fire Rating, this refers to a material which will flake away and vapourize under heat stress, but in doing so, dissipate and remove the heat with it |
| Active Fire Rating |
Active fire protection systems are classified as those systems which seek to extinguish the fire through:
- Detecting the fire early and evacuating the building
- Alerting emergency services at an early stage
- Controlling the movement of smoke and fire
- Suppress and/or starve the fire of oxygen and fuel
|
| Elastomeric |
A polymer which has the elastic properties of rubber. That is, a polymer which can be expanded and contracted and yet still return to its original shape. |
| Fire Resistance Level |
Refers to the time in minutes which a substance will resist - without failure - exposure to heat and flame without a loss of Structural adequacy, Structural Integrity or Insulation. All Fire Resistance Levels are tested within Australia to AS1530 Part 4.
A Fire Resistance Level is given in 3 components. This may be expressed as 60/60/60 which refers to:
- A structural Adequacy of 60 minutes
- Integrity of 60 minutes
- Insulation of 60 minutes.
It is not uncommon to see an Fire Resistance Level expressed as ~/90/30. This is generally used for non-load bearing elements such as a fire door.
An appropriate FRL is given only after rigorous testing to AS1530 Part 4 over different tests.
|
| FRL |
See Fire Resistance Level |
| Insulation |
This is a measure of the temperature rise as experienced on the non exposed (non fire side) of a fire resistant separating barrier. Failure of the product is deemed to have occurred when the measured temperature on the non-fire side exceeds a maximum increase of 180 Degrees Celcius, or an average temperature rise of 140 Degrees Celcius. |
| Integrity |
Refers to the ability of a fire rating compound to restrict the flow of flames and hot gasses but is not a test of its ability to restrict the flow of smoke. Failure in relation to "Integrity" is defined as one or more of the following:
- Continuous flaming on the side not exposed (non fire side) to the test assembly,
- A 'Through' gap into the furnace exceeding sizes as defined within AS1530 Part 4
- Ignition of the so called “cotton wool pad test”
When referring to the Fire Rating level of a substance, it is generally the figure defined under Integrity testing which is used to decide the level of Fire Rating a product has. |
| Intumescent |
A substance which will expand as a result of heat exposure (generally fire), increasing in volume whilst simultaneously decreasing in density. By swelling, the substance forms a char which seeks to encase the material it applied to, thus protecting it from damage. This char is a poor conductor of heat and has low flamability, thus reducing the spread of flame. |
| Mastic |
This refers to putty-like pastes which are generally used in structures as a joint-sealer or filler. Generally, they are 'waterproof'. |
| Passive Fire Rating |
Those Fire Rating solutions that seek to contain the fire by:
- Delaying the growth of the fire
- Using fire rated partitions and doors to prevent the fire and smoke from moving from one compartment to another
- Delaying the collapse of the building structure with fire rated structural columns, so fire services can safely move throughout the building to extinguish the flames
|
| Structural Adequacy |
Refers to the ability of the tested component to remain structurally sound and load bearing during fire testing. To be awarded a Structural Adequacy rating, the component must remain within an allowable rate of deflection for a predetermined time at a predetermined temperature. Generally Structural Adequacy refers to testing on load bearing steel columns and beams |
| Thin film intumescent |
See also "Intumescent". Thin film intumescents refer to that class of intumescent substances which are applied at a lesser density than other intumescents, yet which still form a protective char which seeks to encase the structure it has been applied to. There are two types of thin film intumescent - water based and solvent based |
| Vermiculite |
A chemically inert, hydrated silicate mineral which expands on heating. It is generally used in building construction for its thermal and sound insulation properties. It can be distinguished as a brown/yellow looking material applied to steel and concrete |