InspectAPedia ^TM

Recommendations for gas measurement instruments & gas detector tubes for indoor gas level tests Enter your search terms Submit search form   Search This Website - InspectAPedia.com

• Recommendations for gas measurement instruments, gas detector tubes, Draeger & Gastec, Komyo Rikagaku Kitagawa, RAE, & Sensidyne gas detection tubes & pumps for detection of gases
• Use of a Drager pump or Sensidyne pump and colorimetric gas detection tubes
• How Colorimetric gas detection tubes work
• Using the TIF 8800 Gas Detector & pocket-sized gas detectors
• Warnings about using instruments for detection of toxic gases

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 complete nor authoritative. Seek prompt advice from your doctor or health/safety experts if you have any reason to be concerned about exposure to toxic gases. © Copyright 2008 Daniel Friedman, All Rights Reserved. Information Accuracy & Bias Pledge is at below-left. Use the links at page left to navigate this document or to go to Other Website Topics. Green links at left show where you are in our document & website.

Recommendations for tools and methods for detecting gases in buildings or outdoors

The photograph at the top of this page shows our Sensidyne gas detection hand pump which uses GasTec 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. we like this gas pump method because one or two strokes can produce an accurate measurement of the level of gas in the area with minimum manipulation of the pump by the inspector. However we also make very frequent use of the Draeger gas pump and Drager colorimetric gas detection tubes which we describe below.

Both 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.

Some warnings about relying on instruments for detection of hazardous gases in buildings

OPINION-DF: In 1991, for ASHI, the American Society of Home Inspectors I authored or edited several articles on the use of instruments to test for evidence of dangerous flue gas leaks such as carbon monoxide in residential buildings. We were excited by the possiblity of improving the level of safety afforded by a professional home inspection by permiting home inspectors to use instruments to perform simple screening tests for toxic or dangerous carbon monoxide gas leaks. Inspectors were already using the TIF 8800 described above, but that wide spectrum instrument could not focus specifically on, nor give numeric levels of carbon monoxide gas alone.

Quite a few home inspectors rushed to buy and some continue to use any of a variety of excellent and sensitive specialized pocket-sized gas detectors designed to screen specifically for carbon monoxide. Particluarly in parts of the U.S. where home inspectors had found that the level of expertise offered by their local gas distibution companies was a bit weak, they were anxious to have a more reliable safety check tool for buildings heated by natural or LP gas.

In my view these articles encouraging the use of carbon monoxide detection instruments in the hands of some of these home inspectors was a disaster. Home inspectors who were not technically inclined, home inspectors who were more focused on the bottom line (profit), and inspectors who were looking for a way to simply speed up their inspection while doing less work, simply purchased one of these instruments, turned it on, and left it to check the heating system for CO leakage while they, being efficient and fast fellows, went off to inspect something else. In other words, some home inspectors stopped inspecting the heating system as thoroughly as they had before relying instead on the instrument to do their work for them. Those inspectors, thinking that their job was done, simply reported that the instrument did or did not detect any carbon monoxide, and they disclaimed further responsibilty for the condition of the heating equipment or even for the accuracy of the test they had performed. What was wrong with this approach?

• A complete visual inspection of the heating system, flue vent connector, chimney externals, controls, and safety devices is essential to form a reasonable opinion about the condition, useability, and safety of a heating system. Use of an instrument to check for the presence of a single gas is an inadequate substitute.
• The production of dangerous carbon monoxide varies enormously at a given heating system over a short time and for a variety of reasons. Testing with a door to the boiler room or furnace room open or shut can completely change the supply of combustion air (in some cases) and thus can "turn on" or "turn off" the production of dangerous carbon monoxide.
• Many other safety operating defects may be present and may be very important besides the test for carbon monoxide release.

In sum, there is a place for and good use for test instruments during building investigation, but they are not and should not ever be a substitute for a careful and thorough visual inspection and history-taking by an expert. Those "high speed" inspectors would have performed a better service for their clients by encouraging them to purchase and install smoke detectors and home-use carbon monoxide detectors than to hasten their inspection by using an unattended CO instrument in the home. Our article CARBON MONOXIDE - CO includes a photograph of a simple and effective carbon monoxide detector intended for homeowner installation and use.

Technical Reviewers

Particular thanks are due to experts and also consumers who read these articles and suggest corrections, changes, and additions to the material. Content suggestions, technical corrections and content critique are invited for any of the content at our website.

• Daniel Friedman - principal author/editor of the InspectAPedia ^© Website
• "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
• Critique, contributions wanted: Contact Us to suggest text changes and additions and, if you wish, to receive online listing and credit for that contribution.

More Information on Toxic Gas Detection, Exposure, Test Procedures, Toxicity, and Remedy, & Building Diagnostic Inspections and Repairs

Toxic Gas Exposure Hazards and Test Protocols including links to our toxic gas exposure screening and gas testing protocols.

Gases: Toxic gases, indoor exposure levels, testing, identification

• 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
• 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
• Carbon Monoxide Gas Toxicity hazard levels, poisoning symptoms, & testing
• 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.
• 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.
• Radon Gas U.S. EPA Radon level maps

InspectAPedia ^TM Home & Site Map - Building Inspection, Diagnosis, & Repair, Environmental Inspection & Testing - Research Website

The Mold Information Center: What to Do About Mold in Buildings, When and How to Inspect for Mold, Clean Up Mold, or Avoid Mold Problems

Home Inspection Construction Consulting Services & advice for home buyers

Use this simple, economical mold test kit by following our instructions on how to collect and mail mold samples to our lab

Environmental Inspection, Testing, & Diagnosis On-Site IAQ, Gas, Air Testing, Mold Investigation, Sick Building Diagnosis, Lab Services, & Remediation Plan Preparation - indoor air quality testing, problem source determination, supporting lab work, written remediation plan addressing removal of environmental and other hazards and prevention of their recurrence.

Contact Daniel Friedman for website content suggestions or for fee-paid consulting

	inspect-ny.com Web