09-06 Air gap reference to CSA B64

Question: 09-06Code Section: 7Date: 7 April 2009OBC 2006 Reference: 1.3.1.2; 7.6.2.9

Question: Does an air gap have to comply with CSA B64? I have received a CSA Certificate of Compliance for an “Air Gap for Chemical Dispenser: Aire- Gap, Flex-Gap”. The applicable standard is CSA Standard B125-93- Plumbing Fittings. Table 2 of CSA B64-10 does not list a standard designation for an air gap.

Interpretation: Air gaps are covered by 7.6.2.9. The air gap may be the best form of cross connection control however it is not always practical and is easy to circumvent. The CSA standard B64 does mention air gaps as a backflow prevention method is recommended for extremely hazardous installation.

Note the Building Code defines an Air gap as the unobstructed vertical distance through air between the lowest point of a water supply outlet and the flood level rim of the fixture or device into which the outlet discharges.

Interpretation: Approved at AMES 2009