HC Deb 06 February 1992 vol 203 cc225-6W
Mr. Harry Greenway

To ask the Secretary of State for the Environment what assessment he has made of the effect multi-seat fires may have on means of escape; and what account has been taken of this within the new Building Regulations.

Mr. Yeo

The means of escape provisions of the Building Regulations have always been based on the assumption that there is unlikely to be more than one seat of fire. Accidental multi-seat fires in buildings are so unlikely that it would not be reasonable to make special provision for them under the regulations.

Mr. Harry Greenway

To ask the Secretary of State for the Environment what assessment he has made of the extent to which the removal of requirements for non-combustible materials and materials of limited combustibility will affect smoke levels and fire load in buildings and the unseen spread of fire and smoke within concealed spaces.

Mr. Yeo

The changes to the guidance on the use of non combustible materials and materials of limited combustibility are not expected to have any significant effect on the smoke levels in buildings, which are determined primarily by the smoke produced by their contents, such as furniture and fittings. Likewise, these changes to the guidance are unlikely to affect the unseen spread of smoke and fire, which is prevented by cavity barriers. The new guidance has not dispensed with controls over the positioning of these barriers, and it takes account of the material lining the cavity.

The fire load is likely to be increased in some buildings where more combustible materials are used in the construction of fire resisting walls and floors. However this is not likely to be of any significance for the overall levels of safety. Because they are fire resisting these elements of construction are unlikely to be heavily involved in a fire until an advanced stage is reached, by which time evacuation would have had to have been completed.

Mr. Fry

To ask the Secretary of State for the Environment what effect he expects the deletion of structural non-combustibility requirements from the new building regulations to have on(a) levels of (i) fire severity, (ii) smoke and toxic fumes and (b) likelihood of premature collapse of structures in fires in buildings constructed to the new regulations.

Mr. Yeo

On points(a) (i) and (ii) I refer my hon. Friend to the answer I gave today to my hon. Friend the Member for Ealing, North (Mr. Greenway).

The likelihood of premature collapse should not be affected by the use of combustible materials in the circumstances described in the new guidance to the building regulations. Regardless of their composition fire resisting floors and walls that perform a load bearing function have to maintain that function for the designated test period.

Mr. Fry

To ask the Secretary of State for the Environment what account was taken in drawing up the building regulations tabled on 10 December of the problem of the increasing number of multi-seat fires of deliberate and terrorist origin; and if he will make a statement.

Mr. Yeo

While the value of active fire suppression systems against attacks of deliberate and terrorist origin has been highlighted by the recent spate of incidents, and the new building regulation guidance would have the effect of increasing the number of such installations, the regulations are not an efficient way of countering this problem, compared with good management practices tailored to the particular circumstances, and the vigilance of all concerned. There is a long lead time between changes to the regulations and changes to a significant proportion of the building stock, by which time the nature of the problem may well have changed.