Why isn the hydrocarbon spec as low as the O2 and H2O specs?
It’s all perspective. The BIP helium THC spec is actually the same as the THC spec of our research grade helium. Remember that specifications are an indication of the highest possible concentration of an impurity in the gas; they do not describe the actual amount. The actual amounts of every impurity are typically much lower than the specs indicate. In fact, independent testing by a government air analysis lab in Canada has shown that the C2-C7 hydrocarbon concentrations are less than their method limit of detection of low parts-per-trillion. We have confirmed that work using our own ppb-level volatile organic compounds (VOC) analytical system.
