Detection Tools Advance to Assist Responders

As the years have passed following the terrorist attacks of Sept. 11, 2001, experts in gas detection and air monitoring describe how instrumentation equipment has changed to offer increased protection for emergency response workers.

Dave Wagner
Director of Portable Products, Industrial Scientific Corp.

The post 9/11 era has caused manufacturers of gas monitoring instruments to scramble to meet the needs of the homeland security and first responder markets. While these needs always existed, 9/11 made emergency preparedness a priority and the monies made available by the federal government have sent manufacturers looking to obtain a piece of the pie. The changes have been twofold.

First, there has been an emphasis on increasing detection capabilities with a focus on nuclear, biological and chemical agent detection in order to seek out weapons of mass destruction, and protect the public in the aftermath of a terrorist attack. Sensing technologies such as SAW (surface acoustic wave) and IMS (ion mobility spectroscopy) that were once used primarily in military activities are being adapted for use in instrumentation designed for industrial and commercial applications. These technologies are being coupled into multigas detectors along with more traditional sensors to detect toxic industrial compounds (TICs) and radiation detectors to make a complete anti-terrorism, first response, hazardous material detection tool. Wireless reporting technology is also being used in instrumentation of this type so that units can be placed around large public venues and events that may be targets for terrorist activities such as the Super Bowl. These units will report the status of their sensors to emergency command and control centers to provide 24-hour protection.

The second area of notable change has been the increased emphasis on utilizing existing instrumentation technologies and features in general industrial applications. The realization that large industrial complexes such as oil refineries, chemical plants and metropolitan water and wastewater treatment plants may be threatened by terrorists has caused operators of these facilities to place greater concern on detection of gases such as chlorine and ammonia. Instrument manufacturers have increased their focus on detecting and promoting instruments that detect these compounds.

Dr. Patrick Hogan
Vice President Marketing, Honeywell Analytics

The events of Sept. 11, 2001, had a profound effect on every aspect of how those in charge of homeland security and emergency response plan and implement a range of scenarios, not least towards how responders would cope in a wide variety of disaster situations that would require navigation through areas of toxic or combustible gases, or through dangerous confined spaces.

Quality gas detection products, especially portable products designed to be used by emergency responders, are intended for use in extreme situations, being designed for environmental extremes such as heat or cold, sudden impacts or ingress of dirt, and chemicals or other fluids. These constantly improved designs, coupled with the wide ranges of the gases they can cover, demonstrate the high level of technology and standards applied to the equipment to assist emergency workers in dealing with the majority of security and response issues.

Nonetheless, homeland security organizations and emergency responders are constantly anticipating new eventualities. We have received inquiries for hybrid units that sense for contaminants outside the range of gas detection – not just for toxic and flammable gases, but other hazards such as radiation or chemical warfare agents. Technology advancements in wireless applications have prompted interest in improved communications combining real-time transmission of the gas data combined with geospatial location for greater understanding of the threat scenario. The great disruption that emergency events can cause to communication networks however makes any foolproof improvements a challenge.

Most interestingly we have received requests for “stealth” variations of equipment, evidently intended for use where discretion as a law enforcement agent is vital: These include versions of products produced in dark colors without audible or visual alarms – although we are careful to point out that the latter potential impairs the function of a gas detector to raise the alarm to its full capacity.

As always, we would advise all parties to carefully consider their needs. Look for recognized quality standards, such as the IP 67 Ingress Protection standard that enables the instrument to withstand aggressive operating environments. Consider also important hidden attributes, such as a long battery life and the ability to calibrate or bump test the unit easily in the field by any operator.

Bob Vigdor
Global Sales and Marketing Manager for Portable Instruments, Scott Health and Safety

Prior to 9/11, first responders, industry, and government entities primarily relied on portable and fixed position atmospheric detection systems to determine the concentration levels of oxygen, combustible gases and other common toxic gases found in a local environment due to leaks or accidental releases. Since the attacks on the United States in 2001, first responders now must contend with atmospheric hazards due to purposeful terrorist attacks using calculated amounts of toxins that are intended to injure or kill large segments of a population. With the increasing sophistication of the development and deployment of these terrorist threats comes the need for equally advanced atmospheric monitoring.

Responders to terrorist activity require detection equipment that will advise them on a broad spectrum of lethal atmospheric conditions. This includes detection for the basics such as oxygen concentration; presence of combustible gas; toxic gases; and advanced detection for VOCs, nuclear, chemical warfare agents, and biological threats.

The instrumentation manufacturing community is developing various types of detection equipment to meet this growing threat. Today, several manufacturers have incorporated multiple detection technologies into one instrument that can detect for oxygen, toxic gases, combustible gases, VOCs, radiation and/or chemical warfare agents.

First responders, who are most often first on the scene of every potential attack, are also responsible for determining the validity of a white powder threat and then mitigating those that are hoaxes in order to stave off the unnecessary expense and loss of productivity of a full-fledged hazmat response to false alarms. Broad-screening biodetection tests that quickly detect suspicious levels of bacteria, bacterial spores and viruses are now available because of the response of the instrumentation manufacturers to the 9/11 attacks and subsequent threats or hoaxes.

Jeff Emond
Senior Chemist, Biosystems

Since the events of Sept. 11, 2001, there have been considerable development efforts for “civilian sector” targeted portable detection technology for chemical and biological warfare agents. Historically, the effective detection of chemical and biological agents in the field has been done by technologies exclusively developed through the Defense Departments of European and American nations.

Proven detection technologies for chemical warfare agents are ion mobility spectroscopy (IMS) and surface acoustic wave (SAW). Stringent performance requirements of positive identification and measurement at extremely low levels (ppb/ppt) with presence of cross interferences have demanded two-dimensional designs employing both a separation step followed by detection and quantification. Although there had been aggressive marketing of simple photoionization detectors (PID) for this application, credible third-party testing with actual chemical warfare agents has since shown this technology to be inadequate.

For biological agents (BA), the scenario is far more complex. The virulence of BA and their infectious nature combined with an asymptomatic incubation period places a premium on remote sensing – “standoff detection” versus at the site, or “point detection.”

Standoff detectors for both chemical and biological agents are generally not handheld devices. Instead they are mounted in vehicles, both land and aircraft. They involve sophisticated photonic devices. Early systems for BA simply measured particle size. Current advances involve selective absorbance or fluorescence detection for interrogating particle or gas/vapor composition, thus the harnessing of higher power “laser” light sources and multiple frequency detectors.

Point detection for BA includes both genomics (PCR) and immunoassay type (ELISA) detection technologies. Current systems evolved from benchtop, laboratory devices. Limitations that may remain include the need for colorimetric readers, or other peripheral endpoint detection devices that are not field rugged; the need to replenish perishable reagents; and overcoming matrix interferences, such as dirt. There have been recent advances with genomics-based analyses to eliminate the need for heating steps, which greatly reduces power requirements and complexity of detectors. All of these systems will benefit greatly from micro-machining (MEMs) and microfluidics technologies to increase reliability, reduce or eliminate the need for external reagents, and decrease the cost/complexity of analysis.

As this technology moves from the military to civilian sector first-responder users, there are a number of requirements and features that become increasingly important.

• Overall simplicity of the user interface.
• Design for manufacturability (higher volume, lower cost).
• Design for field servicing/support.
• Development of standard, easy to perform calibration practices.

CM