SS 554 - +A1 : 2016 : 2021

Code of practice for indoor air quality for air-conditioned buildings

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The Code applies to all air-conditioned premises where air-conditioning is used intermittently or continuously, with the exception of residential premises, factory production areas, hospitals, polyclinics and laboratories.

It applies to all types of air-conditioning and air-distribution systems.

The recommended minimum ventilation rates in the Code should be used in conjunction with the SS 553, which provides guidance for the design, construction, installation, testing, commissioning, operation and maintenance of air-conditioning and mechanical ventilation (ACMV) system. Neither SS 553 nor this Code prescribes specific ventilation rate requirements for smoking zones. ASHRAE Standard 62.1 may be referred to if smoking zones are present (see also 5.1.6).

In setting indoor air quality (IAQ) standard, this Code considers environmental factors, which include thermal, physical, chemical and biological factors. The purpose of this Code is to specify indoor air quality that will be acceptable to building occupants, and to minimise the potential of adverse health effects.

Due to the diversity of contaminants generated from indoor and outdoor sources, the contaminants covered in this Code are not exhaustive. The Code provides limits for contaminants commonly found in an indoor environment, and limits for parameters that are indicative of the quality of the indoor air.

Meeting the requirements of this Code may not result in an acceptable indoor air quality for everyone in all air-conditioned buildings. The possible reasons are:

a) Diversity of sources and contaminants in indoor air which may warrant further investigation;

b) Inadequate cleaning of outdoor air which is unacceptable;

c) Variation in occupants’ perception of and preference for different levels of air temperature, humidity, noise, lighting etc.; or

d) Variation in susceptibility of individuals.


General Information

Status Current
Edition 2021
No. of Pages 71
ICS Classification 13.040.20 Ambient atmospheres
91.040.01 Buildings in general
Committee Building and Construction Standards Committee
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