Glossary

D

dB

Decibel – a comparative measurement of sound intensity, generally referring to a reduction measured from one point to another.

dB(A)

An expression of the relative loudness of sound in air as perceived by the human ear. The A-weighted filter corresponds to the fact that the human ear is not as sensitive to sound at the lower frequencies as it is at the higher frequencies.

Document B

An “Approved Document” containing recommendations for demonstration of compliance with the Building Regulations (England & Wales) with respect to fire precautions.

Document E

An “Approved Document” containing recommendations for demonstration of compliance with the Building Regulations (England & Wales) with respect to acoustic provisions.

Document M

An “Approved Document” containing recommendations for demonstration of compliance with the Building Regulations (England & Wales) with respect to access provisions, particularly for people with limited mobility.

Document Q

An “Approved Document” containing recommendations for demonstration of compliance with the Building Regulations (England & Wales) covering the standards for doors and windows to resist physical attack by a burglar. It includes standards on being both sufficiently robust and fitted with appropriate hardware.

Double action

Refers to door assemblies in which the leaves are able to open in both directions of pedestrian travel.

Drop seal

An alternative expression for an automatic threshold seal.