NCC 2019 Volume One Amendment 1
Specification F5.5 Impact sound — Test of equivalence

Specification F5.5 Impact sound — Test of equivalence

1. Scope

This Specification describes a method of test to determine the comparative resistance of walls to the transmission of impact sound.

2. Construction to be tested


The test is conducted on a specimen of prototype wall construction and on a specimen of one or other of the constructions specified in Table 2 of Specification F5.2.


The testing of a construction specified in Table 2 of Specification F5.2 need not be repeated for subsequent comparisons provided complete records of the results, the test equipment and the technique of testing are kept so that identical equipment can be employed and an identical technique can be adopted in the testing of specimens of prototype wall construction.

3. Method


The wall constructions to be compared must be tested in accordance with AS 1191.


A horizontal steel platform 510 mm x 460 mm x 10 mm thick must be placed with one long edge in continuous and direct contact with the wall to be tested on the side of the wall on which the impact sound is to be generated.


A tapping machine complying with ISO 140/6 — 1998 (E) must be mounted centrally on the steel platform.


The sound transmission through the wall must be determined in accordance with AS 1191 except that the tapping machine as mounted on the steel platform must be used as the source of sound.


The impact sound pressure levels measured in the receiving room must be converted into normalised levels using a reference equivalent absorption area of 10 m2.