|
|
Guide to Toxic Gas Measurement Instruments & Gas Detector Tubes for Indoor Gas Level Tests
|
InspectAPedia tolerates no conflicts of interest. We have no relationship with advertisers, products, or services discussed at this website.
Toxic or dangerous gas measurement in buildings: this document discusses tools and methods used to test for the level of toxic and other gases in buildings and in outdoors. In related documents we give references and explanation regarding toxicity of several of the most common indoor gases, based on literature search and obtained from the U.S. government and expert sources.
This text may assist readers in understanding these topics. However it should by no means be considered exhaustive. Seek prompt advice from your doctor or health/safety experts if you have any reason to be concerned about exposure to toxic gases.
Green links show where you are. © Copyright 2013 InspectAPedia.com, All Rights Reserved. Author Daniel Friedman.
Recommendations for tools and methods for detecting gases in buildings or outdoors
While other methods are available for gas detection in or around buildings, (such as eletronic gas detection equipment giving gas level readings in ppm and vacuum canisters for lab analysis) the two most common methods used by building inspectors and trades people for sensitive detection of problem gases in buildings are broad spectrum combustible gas analyzers such as the TIF 8800 GAS DETECTOR, specific gas analyzers for halogens such as the TIF 5000 GAS DETECTOR, and calibrated gas pumps using colorimetric gas detection tubes discussed here.
The companies that provide pump and tube gas detection systems produce a very wide range of very sensitive calibrated gas detection tubes, all of which will work just fine with a single, volume-calibrated pump that draws the air or gas sample through the tube. Color changes and a scale marked on the gas detection tube give a nearly instant reading of the target gas level in the area tested.
Watch out: while a gas detection instrument may itself be highly sensitive and very accurate, variations in building condtions can cause a gas to be present at times and below the limit of detection at other times. Therefore when a gas detection test gives negative results (no gas detected) you should not rely on that result alone if there is a risk of unsafe conditions (such as CARBON MONOXIDE - CO poisoning).
Toxic or Hazardous Gas Detection using Calibrated Pump and Gas Detection Tubes
The photograph at the top of this page shows a Sensidyne gas detection hand pump which currently (2008) uses KitagawaTM gas colorimetric gas detection tubes
to measure the level of gases in a building. Here we were checking the level of carbon monoxide (CO) at a heating system.
Above is the TIF 8800 GAS DETECTOR in use at a gas furnace draft hood, and at left is the TIF 5000 GAS DETECTOR used for refrigerant gas detection including detection of refrigerant gas as a tracer gas if used to check for heat exchanger leaks - something no longer recommended nor permitted where discharge of refrigerants to the environment is a possibility.
We like the Sensidyne gas pump method because one or two strokes can produce an accurate quantitative measurement of the level of gas in the area with minimum
manipulation of the pump by the inspector.
However indoor air quality investigators and others having need to measure concentrations of various gases in indoor or outdoor air also make very frequent use of the Draeger gas pump and Drager colorimetric
gas detection tubes which we describe below, or Gastec Gas Sampling Pumps using gas detection tubes sold by GasTecTM.
Safety note: It is critical that the proper pump and gas detection tube combination be used as gas detection tubes are calibrated to work with particular gas pumps. Using the wrong pump or gas detection tube risks making inaccurate gas measurements - an error which could be fatal in some circumstances. Details are in this article at Warnings.)
All of these gas detection systems use a similar approach for measuring the level of gases in a building. The
Drager system uses a rubber bellows pump which requires more pump strokes than the Sensidyne pump (shown above) but may provide a
wider range of detector tubes and gas sampling approaches. For use by firefighters and fire investigators, Draeger also provides a special
manifold which permits multiple samples to be collected simultaneously to screen for a very wide range of toxic gases which may be present
at a fire scene.
Watch out: be sure to read GAS DETECTOR WARNINGS .
To convert between % and ppm see CONVERT PPM to % CONCENTRATION
Warning: About Selecting the Proper Gas Detection Tube
Gas Tube and Gas Pump Must be Compatible
Colorimeteric gas detection tubes produced by different manufacturers are not necessarily interchangeable among gas detection pumps
Be sure that the gas detection tube you are using is one recommended for use with your gas detection pump - check both the gas detection pump manufacturer's instructions and the gas detection tube manufacturer's specifications.
For example, as we were informed in May 2008 by Nextteq GastecTM detection tube distributor in the U.S., Gastec tubes that are currently available are not intended for use on the SensidyneTM gas detection pump.
At one point in time, Sensidyne had the contract for Gastec tubes and lost it due to rebranding. The tubes they sell now are Kitagawa tubes, not Gastec. We don't want to confuse anyone out there that they can use a Gastec tube with the Sensidyne pump. The Gastec tubes are not calibrated to work with a Sensidyne pump and therefore, the reading could be incorrect and prove fatal in some cases.
Gas Tube Must Be Properly Sensitive to the Gases Being Investigated
Watch out: Be sure to select gas detection tubes designed to detect the proper gases being screened in a building, and also to select the gas detector tube which is calibrated to detect gases at the proper level of concern.
The detection of many gases is supported at varying levels of sensitivity. Selecting a tube which is not sensitive enough may result in failing to detect the presence of the target gas. Selection of a gas detection tube which is too sensitive may result in inability to accurately detect the actual level of gas which is present since the tube will become saturated before the actual gas level has been recorded.
Watch out: in our OPINION using a simple bulb-type pump with a gas detector tube (illustration above) as has been suggested in some older gas detection articles is a bad idea: if one cannot be confident that each depression of the bulb produces an accrate and known gas volume the quantitative measurement of gas concentrations given by the detector tube would be simply nonsense.
...
Frequently Asked Questions (FAQs) about tools & test equipment used to test for or detect toxic gases indoors
...
Ask a Question or Search InspectApedia
Questions & answers or comments about how to detect & measure hazardous gases in buildings.
Ask a Question or Enter Search Terms in the InspectApedia search box just below.
Technical Reviewers & References
Related Topics, found near the top of this page suggest articles closely related to this one.
- Jennifer Moore, Sales Administrator, Nextteq, LLC, Tampa FL, www.nextteq.com 813-249-5888. Nextteq is the master Distributor for Gastec in the United States. According to the company's website, Gastec Gas Sampling Pumps are the industry’s first and only pumps to provide on-the-spot measurement of ambient temperature. [Private email, JM to DF 5/23/08]
- "Choosing and Using a Carbon Monoxide CO Monitor," Dan Friedman, The ASHI Technical Journal, Vol. 2 No. 1, July1991
- "Heat Exchanger Testing, Who's Right?" Dan Friedman, The ASHI Technical Journal, Vol. 2 No. 1, July1991
- "Case History: LP Gas Leak - Using the TIF 8800", Dan Friedman, The ASHI Technical Journal, Vol. 2 No. 1, July1991
- Chimneys, Flues, Woodstoves & Fireplaces: Safety Concerns, safe and proper venting of combustion gases, carbon monoxide hazards
- Dräger MSDS for Dräger CH25301 Air Current Tubes, Page 1 of 2.
Dräger MSDS for Dräger CH25301 Air Current Tubes, Page 2 of 2.
Watch out: the Dräger air current tube or "smoke tube" # CH16631 produces a sulfuric acid gas sulfuric acid H2SO4 /SO3 that is dangerous to life and is highly corrosive. Take a look at our copy of the Dräger MSDS for their CH25301 Air Current Tubes. We stored this MSDS in the box with the rubber bulb and tube cutter provided by Dräger. These air current monitoring tubes are provided with rubber caps so that the tube can be "stopped" or shut down when not in use. But the sulfuric acid was so corrosive that it not only caused the rubbger caps to disintegrate, it actually "burned" or oxidized our copy of the MSDS paper form!
- GASES, EXPOSURE, TESTINGToxic Gas Exposure Hazards and Test Protocols including links
to our toxic gas exposure screening and gas testing protocols.
- Jennifer Moore, Sales Administrator, Nextteq, LLC, Tampa FL, www.nextteq.com 813-249-5888. Nextteq is the master Distributor for Gastec in the United States. According to the company's website, Gastec Gas Sampling Pumps are the industry’s first and only pumps to provide on-the-spot measurement of ambient temperature. [Private email, JM to DF 5/23/08]
- "Choosing and Using a Carbon Monoxide CO Monitor," Dan Friedman, The ASHI Technical Journal, Vol. 2 No. 1, July1991
- "Heat Exchanger Testing, Who's Right?" Dan Friedman, The ASHI Technical Journal, Vol. 2 No. 1, July1991
- "Case History: LP Gas Leak - Using the TIF 8800," Dan Friedman, The ASHI Technical Journal, Vol. 2 No. 1, July1991
- Chimneys, Flues, Woodstoves & Fireplaces: Safety Concerns, safe and proper venting of combustion gases, carbon monoxide hazards
- Air Pollution Toxicology: APTI Course SI:300, Introduction to Air Pollution Toxicology, US EPA Air Pollution Training Institute, Environmental Research Center, Research Triangle Park, NC 27711, Sept. 1993, web search 08/28/2010, original source: http://yosemite.epa.gov/
- A Toxic Gas Testing Plan: A Gas Sampling Plan for Residential and Commercial Buildings lists some of the toxic indoor gases for which we test, depending on the building complaint and building conditions
- CCSP, 2008: Analyses of the effects of global change on human health and welfare and human systems. A Report by the U.S.
Climate Change Science Program and the Subcommittee on Global Change Research. [Gamble, J.L. (ed.), K.L. Ebi, F.G. Sussman,
T.J. Wilbanks, (Authors)]. U.S. Environmental Protection Agency, Washington, DC, USA. Web search 08/28/2010, original source: http://nepis.epa.gov/
- Gas Exposure Hazard Levels: for Toxic Gas Exposure to Ammonia, Arsine, Arsenic, Bromine, Carbon Dioxide, Carbon Monoxide, Hydride, Ozone - allowable exposure levels and hazard levels
- Carbon Dioxide Gas Toxicity hazard level, poisoning symptoms, & testing
- Health Effects of Carbon Dioxide - see "National Advisory Committee for Acute Exposure Guideline Levels (AEGLs) for Hazardous Substances; Proposed AEGL Values, Federal Register Document", http://www.epa.gov/EPA-TOX/2002/February/Day-15/t3774.htm note that these are proposed guidelines
- Carbon Dioxide CO2: Geologic Sequestration Health Effects: "Vulnerability Evaluation Framework
for Geologic Sequestration of Carbon
Dioxide", US EPA, EPA430-R-08-009, July 2008, web search August 2010,original source: http://www.epa.gov/climatechange/emissions/downloads/VEF-Technical_Document_072408.pdf
- Carbon Dioxide CO2: Geologic Sequestration, U.S EPA, web search 08/28/2010, original source:
http://www.epa.gov/climatechange/emissions/co2_gs_tech.html
- GTSP, 2006: Carbon Dioxide Capture and Geologic Storage: A Core Element of a A Global
Energy Technology Strategy to Address Climate Change (PDF, 37 pp., 6.05 MB, About PDF).
April 2006, JJ Dooley et al. Global Energy Technology Strategy Program (GSTP)
- IPCC, 2005: Special Report on Carbon Dioxide Capture and Storage, Special Report of the
Intergovernmental Panel on Climate Change [Metz, Bert, Davidson, Ogunlade,
de Coninck, Heleen, Loos, Manuela, and Meyer, Leo (Eds.)]. Cambridge University Press, The
Edinburgh Building Shaftesbury Road, Cambridge CB2 2RU England
- Carbon Monoxide Gas Toxicity hazard levels, poisoning symptoms, & testing
- Fluorine, Its Compounds, and Air Pollution,: a Bibliography with Abstracts, US Environmental Protection Agency, Office of Air Quality Planning and Standards, Research Triangle Park, North Carolina 27711, December 1976. Web search 08/28/2010, original source: http://nepis.epa.gov.
NOTE: because the EPA's original source of this document in PDF format is damaged we have created a text image file, converted to a new PDF for readability.
- Formaldehyde: US EPA. UFFI (Urea Formaldehyde Foam Insulation) was previously considered a hazard (formaldehyde outgassing). Subsequent research virtually closed concern regarding this material; however formaldehyde appears to remain a health concern for sensitive individuals.
- Greenhouse Gas Overview: Carbon Dioxide: U.S. EPA, web search 08/28/2010, original source:
http://www.epa.gov/climatechange/emissions/co2.html
- Nitrogen Oxides: Air Quality Criteria for Oxides of Nitrogen, Vol III of III, US EPA, EPA600/8-91/049cF, August 1993, web search 08/28/2010, original source: http://nepis.epa.gov [Large PDF 25MB]
Key chapters in this document evaluate the latest scientific data on (a) health effects of NOx measured ill laboratory animals and exposed human populatIOns and (b) effects of NOx on agricultural crops, forests, and ecosystems, as well as (c) NOx effects on visibility and nonbiological materials. Other chapters describe the nature, sources, distribution, measurement, and concentratiOns of NOx m the environment These chapters were prepared and peer reviwed by experts from various state and Federal government offices, academia, and private industry for use by EPA to support decision makIng regarding potentIal risks to public health and the enVIronment Although the document IS not intended to be an exhaustIve literature reVIew, It IS intended to cover all the pertinent literature through early 1993
- Ozone Warnings -
Use of Ozone as a "mold" remedy is ineffective and may be dangerous.
- Sampling for gases in air such as VOC's, MVOC's, toxic chemicals, and combustion products.
Unfortunately no single test or tool can detect all possible building contaminants. We use methods and equipment which can test for common contaminants. If the identity of a specific contaminant is known in advance we can also test for a very large number of specific contaminant gases in buildings.
We use gas sampling equipment provided by the two most reliable companies in the world, Draeger-Safety's detector-tubes and Drager accuro� bellows pump, the Gastec� cylinder pump and detector-tube system produced by Gastec or Sensidyne, and
we also use Sensidyne's Gilian air pump. For broad screening for combustibles and a number of other
toxic gases and for leak tracing we also use Amprobe's Tif8850. All of these instruments, their applications, and sensitivities (minimum detectable limits) for specific gases are described in our Gas Sampling Plan online document.
- Sulfur dioxide & other Oxides: Air Quality Criteria for Particulate Matter and Sulfur Oxides, Vol. III, US EPA, Environmental Criteria and Assessment Office, Research Triangle Park NC 27711, Dec. 1982, EPA-600/8/2-029c. Web search 08/26/2010, original source: http://nepis.epa.gov [large PDF]
- Radon Gas U.S. EPA Radon level maps, web search 2005, original source: http://www.epa.gov/iaq/radon/zonemap/zmapp33.htm
- "Table Z-1 Limits for Air Contaminants, 1910.1000 Table Z-1" OSHA standard for air contaminant limits (http://www.osha.gov/pls/oshaweb/owadisp.show_document?p_table=STANDARDS&p_id=9992) - includes for CO2, Carbon dioxide.........| CAS No. 124-38-9 | 5000 ppm | 9000 mg/m3 limits for carbon dioxide as an air contaminant.
Books & Articles on Building & Environmental Inspection, Testing, Diagnosis, & Repair
The Home Reference Book - the Encyclopedia of Homes, Carson Dunlop & Associates, Toronto, Ontario, 25th Ed., 2012, is a bound volume of more than 450 illustrated pages that assist home inspectors and home owners in the inspection and detection of problems on buildings. The text is intended as a reference guide to help building owners operate and maintain their home effectively. Field inspection worksheets are included at the back of the volume. Special Offer: For a 10% discount on any number of copies of the Home Reference Book purchased as a single order. Enter INSPECTAHRB in the order payment page "Promo/Redemption" space. InspectAPedia.com editor Daniel Friedman is a contributing author.
Or choose the The Home Reference eBook for PCs, Macs, Kindle, iPad, iPhone, or Android Smart Phones. Special Offer: For a 5% discount on any number of copies of the Home Reference eBook purchased as a single order. Enter INSPECTAEHRB in the order payment page "Promo/Redemption" space.
|
- Best Practices Guide to Residential Construction, by Steven Bliss. John Wiley & Sons, 2006. ISBN-10: 0471648361, ISBN-13: 978-0471648369, Hardcover: 320 pages, available from Amazon.com and also Wiley.com. See our book review of this publication.
- Decks and Porches, the JLC Guide to, Best Practices for Outdoor Spaces, Steve Bliss (Editor), The Journal of Light Construction, Williston VT, 2010 ISBN 10: 1-928580-42-4, ISBN 13: 978-1-928580-42-3, available from Amazon.com
- The Journal of Light Construction has generously given reprint permission to InspectAPedia.com for certain articles found at this website. All rights and contents to those materials are ©Journal of Light Construction and may not be reproduced in any form.
- ...
|