Make Your PID More Accurate

Photoionization detectors (PIDs) are an important tool for hazmat responders. Over the last 40 years, their usage has grown due to their high sensitivity and response to a wide variety of gases and vapors. The most common PIDs, equipped with a 10.6 eV source, can measure hundreds of different volatile organic compounds. They provide a readout that corresponds to concentration, making them useful for characterizing scenes involving toxic gases.

Being a detection technology, PIDs only alert the user to the presence of a gas substance; they can not identify the gas. In fact, each gas has a different response profile, meaning the stated concentration is only accurate for the gas to which the instrument was calibrated to isobutylene. Correction factors are available for many chemicals, converting the output to an accurate concentration for the actual sample.

Pairing a PID with the ThreatID which can identify the gas in question provides much more information to accurately assess and address toxic gas leaks.  The ThreatID is a chemical analyzer that uses FTIR spectroscopy with its unique interchangeable gas module.  The two systems are synergistic.  Identifying the chemical in question with the ThreatID allows the user to enter the proper correction factor so the PID can report the actual sample concentration.  Additionally, the identification allows other critical information, such as the IDLH value of the gas, to be determined.  This information can be critical to making a scene safe and addressing the problem.

In a way, the ThreatID and a PID make an ideal instrument combination for response to emergencies involving toxic gases and vapors.  The sensitive, real-time detection capabilities of a PID make it an ideal solution for finding the highest concentrations of gases from which to gather a sample and identify with the ThreatID.  Once the sample has been measured and identified with the ThreatID, the integrated ThreatAssist database gives the PID correction factor for the identified material, which can be directly entered into the PID to provide accurate concentration measurements.  Used together, the ThreatID and a PID can provide both the identity and accurate concentration of an unknown gas, giving users the key information needed to handle gas and vapor emergencies.

The ThreatID is an accurate gas identifier of over 5,000 toxic industrial and volatile organic gases in an easy-to-use and affordable package.  By combining well-known FTIR spectroscopy, a long path-length gas cell, and RedWave’s customer support, the ThreatID fills the gas identification gap present in many teams’ equipment capabilities.