Technical Clarification

Internal sound levels in 95% of the nominated areas

Erratum Number



A qualified acoustic specialist must nominate an appropriate test methodology noting the described methodology below, where only one example space per Room Category is to be measured, as per the IEQ-5 Acoustic Quality credit criteria.

Measurements should be carried out to British Standard BS EN ISO 140-4:1998 by a suitably qualified acoustician. Each measurement must be taken over a period of not less than 5 minutes.Measurements should be taken in a minimum of 3 locations in rooms at a height of 1.2 m above the floor level and at least 1m away from any surface. Measurements should be taken when the nominated areas is unoccupied, but with all fans and other base building services running, and with windows open as necessary for normal operation of the building.

  • In the Credit Criteria remove the first sentence; ‘Internal sound levels in the nominated areas are appropriate and relevant to the activity type in each room in accordance with SANS 10103:2008.’; and replace with; ‘Internal sound levels in 95% of the nominated areas are appropriate and relevant to the activity type in each room in accordance with SANS 10103:2008. Internal sound levels measured in the identified worst-case Example Area, in each Area Category, must not exceed the prescribed noise levels recommended by SANS 10103:2008. If an identified worst-case Example Area does not meet the prescribed ambient noise level criteria, a second space or room, representing the next worst case within the Area Category, may be identified and tested (provided the first Example Area does not exceed 5% of the total nominated area). This process may continue until either the Example Area meets the criteria, or more than 5% of the total nominated area has failed.’
  • In Credit Criteria and the Additional Guidance sections, remove the following wording: ‘if the building owner is the applicant and also occupies more than 75% of the building.’

The “worst case scenario in its Area Category” is defined as follows:

  • In case of a typical floor, the worst-case floor should be defined as the floor that is closest to traffic noises or mechanical system plant areas, whichever presents the loudest ambient contribution. The qualified acoustic specialist should identify the typical floor and provide the justification required.
  • In the case of open plan spaces, the same principal applies, i.e. the worst-case open plan space should be the area closest to traffic noises, outdoor mechanical systems, or an indoor plantroom. Again, this would be determined by the source which provides the highest contribution in terms of noise level, determined and justified by the acoustic specialist.
  • In case of enclosed or cellular spaces (typically less than 50 sqm), the definition of the worst-case space, will be the same definition applicable to the open plan space above. The process of identifying and justifying the worst-case Example Area needs to occur for each individual enclosed Room Category definition, as defined in the Credit Criteria.


Technical Clarification

Definition of ‘extended period of time'

Erratum Number




The GBCSA will accept the Interiors Tool description that ‘where a person is expected to work for a period longer than one continuous hour per day’ is equated in the EBP Technical Manual to ‘a space where a person is expected to work, or remain for an extended period of time’ and is a REGULARLY OCCUPIED SPACE.
The further definition/words in the Interiors Occupied Space (OS) don’t apply to the EBP Tool and the definitions with in the EBP Technical Manual as well the definitions within each credit should be taken into account when understanding and defining what REGULARLY OCCUPIED SPACE is for that specific credit.


Was this article helpful?
0 out of 0 found this helpful
Have more questions? Submit a request


Powered by Zendesk