Passive Fire Protection, Part 2

I introduced the concept of Passive Fire Protection in a previous Blog article that can be found by following this link.

In this short article, there are some brief descriptions of some of the terms that are commonly used when discussing or describing Passive Fire Protection.
Fire-resisting structures

Many premises are divided into different areas by fire doors and fire-resisting walls and floors. These are partly designed to keep a fire within one area, giving people more time to escape. Within your building, you should identify which doors, walls and floors in your building are fire-resisting. There may require access to information available from when the building was built, allowing for the affects of alterations, or even from a previous fire certificate. High-risk areas should be separated from the rest of the premises by 30-minute fire-resisting construction. Normally if there are fire doors in a wall, then the wall itself will also need to be fire-resisting. If a wall or floor is required to be fire-resisting then you should not make any holes in it, e.g. for extra doors or pipe ducts, without consulting a competent person and making good the wall penetrations.
Fire-resisting door

This relates to more than just the door, it refers to the complete construction of door, frame, all door hardware (including the intumescent products and smoke seals where appropriate) which has been tested to prove its fire resistance performance to a particular standard.
Fire Door to FD30 or FD30S

This relates to purpose designed and built fire-resisting door assemblies with a minimum fire resistance of 30 minutes. The 30 figure indicates the door’s performance time in minutes. A letter ‘S’ after the figure denotes a requirement for smoke seals to be fitted so as to restrict the passage of smoke, including cold smoke.
Intumescent strip

The intumescent strip is a strip of special material that is fitted around the edges of a fire door and which swells to several times its original volume when subjected to heat. During a fire it will expand to fill the gap between the door and the frame providing a fire, heat and smoke resistant seal, thereby improving the door’s fire resistance.
Fire-resisting glazing

The most common type of fire-resisting glazing is the easily identifiable 6 mm Georgian wired glazing. Clear fire-resisting glazing (such as Pyroglazing) is available and can often be identified by a mark etched into the glass, usually in the corner of the glazed panel, to confirm its fire-resisting standard. This mark is not compulsory, but the marking of glass is supported by the Glass and Glazing Federation.
Smoke seal/strip

This is a rubber or synthetic strip fitted around the edge of a fire door to restrict the passage of smoke between the door and the frame. Doors requiring a smoke seal have the letter ‘S’ after their performance time in minutes in their designation (for example FD30S). The smoke resistance of the door when fitted with the strip must have been tested to standards in BS476: part 31.1, 1983.
Protected (fire escape) route

This is an escape route out of a building offering a degree of protection from fire and smoke emanating from rooms opening onto it. This may relate to the main staircase, landings and corridors of the premises that lead to a final exit. A protected route will provide varying degrees of protection from fire and smoke in accordance with risk (a 30-minute protected route, for example, will be enclosed with construction giving 30 minutes of fire resistance and containing 30-minute fire-resisting doors with smoke seals (FD30S)).