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Zero Air Calibration Gas Cylinders
Certified Zero Air calibration gas provides an ultra-pure, hydrocarbon-free baseline engineered for zeroing portable gas detectors, flame ionization detectors (FID), photoionization detectors (PID), and continuous emission monitoring systems (CEMS). Formulated with a synthetic blend of 20.9% Oxygen balanced with ultra-high purity Nitrogen, our Zero Air guarantees total hydrocarbons (THC) below 0.1 ppm, preventing false offsets during bump testing and span calibrations.
Whether eliminating ambient background contamination during field calibration or running stable combustion air to laboratory analytical instruments, Cal Gas Direct supplies NIST-traceable Zero Air packaged in rugged, lightweight portable cylinders and high-capacity stationary cylinders.
Zeroing gas detectors using ambient "fresh air" exposes sensors to background contaminants—such as trace vehicle exhaust, solvent off-gassing, and elevated CO2 levels—leading to baseline distortion and compromised safety metrics: