Three years have passed since 9/11 and Americans continue to adapt to the "new normal." Our tools change along with us, and new solutions arise from necessity.
Flame and gas detection instrumentation has long been used by industry, when combustible gas meters warned of methane buildup in coal mines and no doubt saved countless lives. Subsequent instruments were built upon that early technology and produced gas detectors for oxygen deficiency and common industrial contaminants such as carbon monoxide and hydrogen sulfide. Later on, hydrocarbons produced by oil tanker spills became detectable as well. Wall-mounted or "fixed" instruments found their way into factories while portable, personal monitors and alarms traveled into confined spaces along with utility, municipal and remediation workers.
Crossover use of gas detection instruments by firefighters is a natural progression as firefighters are frequently the first responders to arrive at the scene of emergency calls. Portable carbon monoxide and combustible gas monitors are logical choices for residential calls concerning leaky furnaces and gas lines. Traces of accelerants can be detected in the aftermath of suspicious fires through use of portable photo ionization monitors.
Some older gas detection technologies have remained and still perform well; catalytic combustible sensors, electrochemical toxic gas sensors, and photo ionization sensors for volatile organic compounds. These sensors types can detect common although highly toxic industrial chemicals (TICs) such as chlorine, ammonia and hydrogen sulfide that could potentially be used as weapons of domestic terrorism. However, events upon U.S. soil and elsewhere in recent years have created a new urgency in the development of new technologies for these critical tools. Detection of chemical warfare agents (CWAs) as well as the ability to provide secure perimeter monitoring of large areas has become an all-too-real necessity.
Firefighters and anyone in need of gas detection instrumentation fortunately have an array of tools and choices. Newer portable multi-gas detectors offer catalytic, electrochemical and photo ionization sensors for combustible and toxic gases as well as trace hydrocarbons in one small and wearable unit. Other instruments incorporate innovative surface acoustic wave (SAW) technology with electrochemical cells, which together can pickup nerve, blister, blood and choking chemical warfare agents. However, ordinary self-contained breathing apparatus (SCBA) and turnout gear may not be sufficient protection if CWAs are indeed present. A CBRN-approved SCBA or a fully encapsulating suit may be necessary in such an event.
Infrared sensors have been available for portable instruments only in the last few years. Firefighters may find this sensor type to be especially useful for confined space pre-entry checks after carbon dioxide extinguishing. Infrared sensors are also used along with spectral matching technology in stand-alone flame detectors for hydrocarbon fires from gasoline, kerosene, diesel fuel, natural gas and liquefied petroleum gas. Flame detectors connect to alarm systems and automatic fire extinguishing systems to aid fire brigades working within oil, gas and petrochemical facilities. Optical gas detection systems detect combustible gases below the lower explosive limit (LEL) over an open path up to several hundred feet long, also useful on offshore platforms and for refineries and petrochemical storage areas.
Transportable perimeter monitoring systems developed as fixed systems originally designed for industrial use were re-tooled to protect large gatherings of people and vital service facilities. Political conventions, mega-sporting events, holiday celebrations, municipal water reservoirs, power stations, mass transit stations and defense manufacturing plants can establish a more secure perimeter by installing a network of gas monitoring units. These wireless and movable systems can be set up in temporary or permanent sites and communicate live gas readings to a central monitoring location, helping first responders to reduce chemical exposure risk.
As our society's concerns expand, so does our knack for problem-solving. The gas detection industry has responded by refining existing technologies and designing new strategies and tools. No one may claim miracle solutions, but firefighters and other first responders may surely look forward to innovative answers to meet the challenges of our rapidly changing world.
Leslie Mitchell is a marketing and communications specialist for Mine Safety Appliances Co. (MSA).