Accurate measurement of temperature, pressure, level, humidity and flow are essential to equipment and systems operation. Inaccurate instrument readings can have a cascade affect on HVAC systems, particularly large ones, and energy efficiency can suffer greatly when instruments are not properly calibrated. It is important to understand calibration, how to properly calibrate instruments, and how often it is required.
Calibration is a process in which measuring instruments are configured to align with the established standard. Many instruments require calibration every 12 months, but some must be calibrated on a monthly or quarterly basis, depending on protocols and the device’s criticality. A good time to calibrate instruments is during regular preventive maintenance.
Equipment used to perform calibration must be certified by NIST (National Institute of Standards and Technology), and thorough documentation is necessary whenever calibration occurs in order to maintain traceability to NIST standards. Single-point calibration can be used in some applications, but multi-point calibration, in which readings are verified over a multiple-point range, may be required where even greater precision is required. Also, it should go without saying that high-quality instruments should be used wherever possible to provide and maintain optimal accuracy. Inferior instruments provide inferior results.
PJM Mechanical Contractors, Inc. is a multi-faceted mechanical contractor providing construction and installation, service and maintenance, and design/build services in a comprehensive range of mechanical disciplines that include HVAC, plumbing, controls, refrigeration, custom metal fabrication, piping, and backflow preventer testing. PJM primarily serves clients in pharmaceuticals, manufacturing, healthcare, institutional, and other various commercial and industrial sectors.