Differential pressure gauges are used for the mandatory annual certification of backflow prevention devices. Yet many owners fail to check or calibrate their pressure gauges annually, despite the obligation to do so under article 7.2 of CSA standard B64.10.1-17. Calibrating your pressure gauge annually may seem excessive and costly at first glance, but it is essential for safety and reliability reasons, to avoid loss of accuracy and damage to parts through repeated use.
For accurate results during backflow preventer certification, the pressure indicated on the dial of the manometer must represent the exact pressure of the manometer, otherwise it must be calibrated. Also, a broken or damaged pressure gauge will invalidate the device’s certification.
What’s more, an uncalibrated pressure gauge can give erroneous results during field testing of the backflow preventer. This error can easily be avoided by calibrating the pressure gauge annually in a recognized laboratory. However, even if this process is followed every year, the pressure gauge may lose its accuracy or break if it is used very frequently. In this case, a repair followed by a second calibration may be necessary.
In conclusion, it is mandatory to check and calibrate your differential pressure gauge at least once a year to guarantee its reliability when certifying backflow prevention devices, thus ensuring the safety of the drinking water supply system in buildings, and consequently the health of its users.