Thermal imaging camera

Thermal imaging camera

A thermal imaging camera (colloquially known as a TIC) is a specific type of thermographic camera used in firefighting. By rendering infrared radiation as visible light, they allow firefighters to see areas of heat through smoke, darkness, or heat-permeable barriers. Thermal imaging cameras are typically handheld, but may be helmet-mounted. They are constructed using heat- and water-resistant housings, and ruggedized to withstand the hazards of fireground operations. While expensive pieces of equipment, their popularity and adoption has been increasing in recent years.

Construction

A thermal imaging camera consists of five components: an optic system, detector, amplifier, signal processing, and display. Fire-service specific thermal imaging cameras incorporate these components in a heat-resistant, [citation|last=Molinaro|first=Hope|title=Where there's Smoke...|journal=Plastics Engineering|date=2004-04-01|pages=14|volume=60|issue=4|accessdate=2008-09-22|url=http://proquest.umi.com/pqdweb?did=672911291&sid=2&Fmt=6&clientId=20886&RQT=309&VName=PQD] ruggedized, and waterproof housing. [See any manufacturer's promotional material, e.g. cite web|url=http://goliath.ecnext.com/coms2/gi_0199-3319214/RAYTHEON-UNVEILS-THERMAL-EYE-X100XP.html|title=Raytheon Unveils Thermal-Eye X100XP Thermal Imaging Camera|date=2003-12-01|accessdate=2008-09-19] These parts work together to render infrared radiation, such as that given off by warm objects or flames, into a visible light representation in real time. The camera display shows infrared output differentials, so two objects with the same temperature will appear to be the same "color". Many thermal imaging cameras use grayscale to represent normal temperature objects, but highlight dangerously hot surfaces in different colors. [cite web|title=Introduction of the latest thermal imaging camera – the Scott Eagle Imager™ 320|url=http://www.firefightingincanada.com/content/view/2423/179/|date=2008-08-22|accessdate=2008-09-19|publisher=Firefightingcanada.com]

Cameras may be handheldcitation|journal=Fire Chief|last=Smith|first=Hezedean|volume=51|issue=8|pages=120|issn=0015-2552|title=Image Conscious|date=2007-08-01|year=2007|url=http://search.ebscohost.com/login.aspx?direct=true&AuthType=ip,url,uid&db=bch&AN=26383095&site=ehost-live|accessdate=2008-09-19|issn=0015-2552] or helmet-mounted.citation|last=Boyd|first=Jonathan|title=Using Hands-Free Thermal Imaging Cameras|journal=Fire Engineering|date=2007-05-01|pages=95-97|issn=0015-2587|volume=160|issue=5|url=http://search.ebscohost.com/login.aspx?direct=true&AuthType=ip,url,uid&db=bch&AN=25132700&site=ehost-live|accessdate=2008-09-17] A handheld camera requires one hand to position and operate, leaving only one free hand for other tasks, but can be easily transferred between firefighters.

The NIST Fire Research division is the lead government agency developing performance standards for fire service thermal imaging cameras in the United States, although the U.S. Army Night Vision Laboratory has contributed to the effort.citation|last=Madrzykowski|first=Dan|coauthors=Steve Kerber|journal=Fire Engineering|date=2008-05-01|year=2008|title=Technology Roundup: Firefighting Technology Research at NIST|pages=68|volume=161|issue=5|issn=0015-2587|url=http://search.ebscohost.com/login.aspx?direct=true&AuthType=ip,url,uid&db=bch&AN=32456939&site=ehost-live|accessdate=2008-09-18] Preliminary recommendations from the field include visible low-battery warnings, ability to withstand full immersion in water, and the ability to provide meaningful visual readouts beyond 2,000°F (~1,100°C). [citation|last=Little|first=David A.|title=Safety First|date=2005-04-01|volume=50|issue=4|page=92|issn=0015-2552|journal=Fire Chief|url=http://search.ebscohost.com/login.aspx?direct=true&AuthType=ip,url,uid&db=bch&AN=20786754&site=ehost-live|accessdate=2008-09-18]

Usage

Since thermal imaging cameras can "see" through darkness or smoke, they allow firefighters to quickly find the seat of a structure fire, or see the heat signature of visually obscured victims. They can be used to search for victims outdoors on a cool night, spot smoldering fires inside a wall,cite book|last=Norman|first=John|title=Fire Officer's Handbook of Tactics|url=http://books.google.com/books?id=VPxWmvKmzZkC&pg=PT88&dq=%22thermal+imaging+camera%22+RIT&as_brr=3&sig=ACfU3U2LOPFL86K4vvGMAdX3jbtQaMwDTg#PPT175,M1|accessdate=2008-09-19|date=2005|publisher=PennWell Books|isbn=159370061X] or detect overheating electrical wiring.cite book|title=Fireground Strategies|last=Avillo|first=Anthony|page=421|url=http://books.google.com/books?id=7uP1rC7W9jkC&pg=PA421&dq=%22thermal+imaging+camera%22&sig=ACfU3U2b_Y8Qwnvoc-36c9NhjYkmTuebiw|accessdate=2008-09-18|publisher=PennWell Books|date=2002|isbn=087814840X]

In addition to the ability to see through dense smoke, thermal imaging cameras also can see materials involved in spontaneous, low level combustion. In one documented instance, a TIC was used to isolate a smoldering hot spot in a grain storage facility; by isolating and removing only the affected grain, 75% of the stored crop was saved. [citation|last=Buzard|first=Eric|title=Fresh Set of Eyes|journal=Fire Chief|volume=49|issue=9|issn=0015-2552|pages=82-85|date=2005-09-01|url=http://search.ebscohost.com/login.aspx?direct=true&AuthType=ip,url,uid&db=bch&AN=18511970&site=ehost-live|accessdate=2008-09-18] In another, Tennessee firefighters used a thermal imaging camera to detect a hidden fire inside a cinder railroad bed, resulting in an estimated $500,000 cost avoidance. [cite web|title=AEDC Helps Local Company Save Nearly $500,000|date=2002-01-24|url=http://search.ebscohost.com/login.aspx?direct=true&AuthType=ip,url,uid&db=bch&AN=32W1494378977&site=ehost-live|accessdate=2008-09-19|publisher=eMediaMillWorks] Thermal imaging cameras have also been reported to be particularly useful for fighting fires in cellulose insulation. [citation|last=McLees|first=Mark|journal=Firehouse|date=2008-06-01|title="Going Green" May Make You "See Red"|volume=33|issue=6|pages=46-49|accessdate=2008-09-22|url=http://proquest.umi.com/pqdweb?did=1501984401&sid=2&Fmt=3&clientId=20886&RQT=309&VName=PQD]

Prototypes of helmet-mounted thermal imaging cameras were first publicized in 1992, [citation|last=Marks|first=Paul|title=Helmet Camera Lends a Hand to Firefighters|journal=New Scientist|date=1992-09-19|volume=135|issue=1839|page=22|issn=0262-4079|url=http://search.ebscohost.com/login.aspx?direct=true&AuthType=ip,url,uid&db=bch&AN=9211091366&site=ehost-live|accessdate=2008-09-18] but a detailed evaluation of their performance in real world situations was not published until 2007. The model evaluated in 2007 weighed approximately 1.5 lbs, substantially increasing weight over an unadorned helmet. However, the ability to "use the devices while they were also pulling hose and carrying tools" was favorably received by firefighters evaluating the product. Benefits of helmet mounted TICs included that multiple firefighters each observed different aspects of a fire, while drawbacks included firefighters relaxing safety discipline. In timed testing, teams of firefighters with helmet-mounted cameras completed search tasks substantially faster, were disoriented less, and used less air than teams with a single handheld camera, who in turn fared better than teams with no TIC at all.

A limitation of these and similar devices has been their poor depth perception (the user has a hard time judging how far away objects are).cite web|last=Kemah (Texas) Fire Department|url=http://www.kemahfire.com/sog/Thermal_Imager.pdf|format=PDF|title=Thermal Imaging Camera|pages=2] [cite book|first=J. Michael|last=Lloyd|title=Thermal Imaging Systems|publisher=Springer|year=1975|isbn=0306308487|pages=70 "we usually consider that depth is not significant."] This increases the likelihood that the user will trip over or run into obstacles, or have other distance-related problems.

History

Thermal imaging technology was in use in specialized law enforcement and military applications before its adoption by the fire service.

Acceptance of thermal imaging cameras by the fire service has been hampered by the cost of the cameras. The Seattle Fire Department acquired its first thermal imaging camera in 1997, for a cost of $16,000. [citation|journal=Seattle Times|last=Tu|first=Janet I-Chin|issn=07459696|date=2007-08-18|url=http://proquest.umi.com/pqdweb?did=31192089&sid=2&Fmt=3&clientId=20886&RQT=309&VName=PQD|accessdate=2008-09-22|title=Technology at Work -- Firefighters Look Into the Future -- New Computers, Camera Can Spot Hidden Dangers] In 2000, the "Los Angeles Times" called the thermal imaging camera " [p] erhaps the best advance in fire equipment in the last 25 years—and the most expensive".cite web|title=New Firefighter Gear Calls for Money to Burn|last=Ivey|first=Catherine|date=2000-04-02|accessdate=2008-09-19|url=http://articles.latimes.com/2000/apr/02/news/mn-15085|publisher="Los Angeles Times"] Fire departments have pursued various sources and methods to fund thermal imaging cameras including direct budgeting, grants,citation|last=Goodwin|first=John W. Jr.|journal=The Vindicator|date=2008-07-30|title=Liberty, Ohio, firefighters receive FEMA grant|url=http://search.ebscohost.com/login.aspx?direct=true&AuthType=ip,url,uid&db=krh&AN=2W62W6544237007&site=ehost-live|accessdate=2008-09-17] and charity donations, [cite web|title=Employing heat for safety's sake|url=http://www.riverheadfd.org/02_news_archives.htm|date=2002-04-11|accessdate=2008-09-19|publisher=Riverhead, NY Fire Department] among others. One fire chief observed that the same sorts of cost issues plagued SCBA acquisitions during their initial adoption. In 2001, FEMA began issuing grants under the Firefighter Investment and Response Enhancement (FIRE) Act, which provided $100 million to U.S. fire agencies during that fiscal year. Many departments used these funds to purchase thermal imaging cameras. [citation|title=A Financial Shot in the Arm|last=Elliott|first=Fred|journal=Occupational Health & Safety|volume=70|issue=11|date=2001-11-01|pages=32|url=http://proquest.umi.com/pqdweb?did=90045999&sid=2&Fmt=3&clientId=20886&RQT=309&VName=PQD|accessdate=2008-09-22]

As departments began acquiring thermal imaging cameras, they were typically assigned to specialized units, such as heavy rescue and truck companies. Thermal imaging cameras are routinely assigned to Rapid Intervention Teams, to enable them to more effectively reach and free trapped firefighters.cite book|title=Structural Firefighting|last=Klaene|first=Bernard J.|coauthors=Russell E. Sanders|pages=135|publisher=Jones & Bartlett|date=2007|accessdate=2008-09-19|isbn=0763751685|url=http://books.google.com/books?id=JpW0nuK2p64C&pg=PA135&dq=%22thermal+imaging+camera%22+RIT&sig=ACfU3U1XWvnNzO5d6mHrPJqizO_bFLI3XA]

Since 2003, the lack of a properly used thermal imaging camera has been recognized by NIOSH as an avoidable factor contributing to firefighter injuries and deaths.cite book|title=Firefighter Rescue & Survival|last=Kolomay|first=Richard|coauthors=Robert Hoff|url=http://books.google.com/books?id=IyQgMl4bmNYC&pg=PA127&dq=%22thermal+imaging+camera%22&sig=ACfU3U3El7uJBbvyDrVP5clpZCoJCoERGw#PPA2,M1|accessdate=2008-09-18|publisher=PennWell Books|date=2003|isbn=0878148299]

ee also

*Flame detector

References


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