Is that mechanical ventilation, air handling or air-conditioning?

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It’s obvious, is it not (to mechanical designers, contractors, service technicians,¬†fridgies)? Well, maybe not to building certifiers and the facility managers (and contractors) who suffer from the result of this common misunderstanding.

AIRAH’s maintenance bible DA19 HVAC & R Maintenance makes a clear distinction in the title. It’s about Heating, Ventilation, Air Conditioning and Refrigeration systems. What brought this up is AIRAH is currently working with the ABCB on some really important work to reference the current (2002) or a modification of it in the BCA DTS provisions.

But sitting above this further up the regulatory “tree” from AS1668.2 are some key regulatory issues for successful application of building control measures.¬†They are:

1/ the apparent confusion in application and interchangeability of the words ventilation/air handling versus air conditioning;
2/ the subsequent lack of understanding in the building industry (and particularly amongst building certifiers/surveyors and facility managers) of the relevant installation and maintenance procedures for mechanical ventilation / air handling systems; and
3/ the implications of this for installation standards and maintenance procedures in statutory certificates; and

Why is this important?

This needs sorting to ensure that the hazards (smoke and other gases of combustion, air contaminants, microbes and pathogens etc) which affect the level of risk for systems which handle air are more successfully allocated risk controls in statutory documents by building certifiers/surveyors to assist facility managers better communicate with mechanical designers and contractors.

The use of the phrase “or air-conditioning systems” in Clause F4.5 b) (references AS1668.2) of the BCA DTS provisions seems to have compounded this misunderstanding amongst building surveyors and facility managers. Whilst to the informed, this presumably was intended to mean systems that condition and ventilate, the use of the word “or” between the two terms is ambiguous, maybe confusing(?).

There is frequently application in statutory certificates of maintenance procedures to air-conditioning systems which do not handle air. Whilst this is a unique education challenge for the Regulators and Building Certifiers/Surveying Industry Associations the ongoing failure to meet that challenge continues. In addition, maintenance procedures for smoke hazard management systems are frequently applied in statutory certificates to air conditioning systems which do not handle air.

In Part 4 of the BCA Ventilation there are 3 performance requirements which interchangeably refer to ventilation / outdoor air /mechanical air-handling system. Then there is the use of the phrase “or air-conditioning systems” in Clause F4.5 b) of the BCA DTS provisions. I consider this could be simply resolved by clarification that this reference is to the part of an air-conditioning system related to mechanical ventilation or reference to air-conditioning deleted all together. The appropriate transition may be the former. Alternatively the reference to ventilation and air-conditioning could be deleted and reference to air handling substituted. This has already been done in Table I1.6 Safety Measures – Air Handling Systems of Clause I1.1. Again reference is then made in Clause I1.2 to Mechanical Ventilation.

Interestingly AS3666.1, as a referenced standard under Clause F4.5 b) of the BCA DTS provisions, refers in its scope of application to air-handling systems. Also, the scope of application of AS3666.1 excludes 2 systems which are being increasingly called up by building surveyors as requiring maintenance procedures related to air handling systems.

So what is the way forward? Education on air handling and ventilation systems and the relevant installation standards and maintenance procedures. Education as to the difference and a change in the use of the terms in the BCA? Also written by building certifiers/surveyors. Enough said.

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2 Responses to “Is that mechanical ventilation, air handling or air-conditioning?”

  1. Paul Mackie says:

    does commercial A/C have to be maintained monthly ?

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