Unidentified chemical drums discovered during a home inspection might indicate an environmental site contamination hazard.

Responding to Risk of Odorless Gases & Chemicals in Buildings
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Should we worry about odorless building contamination sources: gases, chemicals, products?
Examples of potentially harmful odorless chemicals or gases in buildings
Strategy for deciding how far to go in testing for invisible, odorless indoor hazards
How to identify odors or gases by type, source, and toxicity. Noxious odors or smells in buildings can be diagnosed and cured
Questions & answers about odorless gas and chemical hazards in buildings

Odorless building hazards: chemicals & gases: this article discusses what to do about indoor contaminants that might not smell or give any ready indication of their presence.

InspectAPedia tolerates no conflicts of interest. We have no relationship with advertisers nor with topics or services discussed at this website.

This website series provides articles on to diagnose, test, identify, and cure or remove a wide range of obnoxious or even toxic odors in building interiors, building mechanical systems, or in building water supply. We discuss odors from a variety of sources including animals including pets, dogs, cats, or unwanted animals or dead animals, formaldehyde odors in buildings from building products or furnishings, plumbing drains, plastic or vinyl odors from building products, flue gases, oil tanks or oil spills, pesticides, septic odors, sewer gases, and even abandoned chemicals at properties.

Our page top photo shows outdoor evidence of a radon mitigation system at a building. Radon is an example of an odorless, colorless gas that at elevated levels can be a health hazard for building occupants.

For smells or odors in New Orleans, possibly associated with the 2010 Gulf Oil Spill, readers can use the odor diagnosis advice hear to distinguish between gulf oil spill odors and other building odor sources. Readers should also see Gulf Oil Spill & Air Quality. Readers should see ODORS, Smells, Gases in Buildings-Diagnosis & Cure, also see our ODOR DIAGNOSIS CHECKLIST for a quick check that can help identify the source of smells in buildings and see SMELL PATCH TEST to Track Down Odors.

The photo above shows steel chemical drums that we discovered on a residential property during a home inspection. Not only did these steel drums raise a question of possible environmental contamination of this site, even worse, they were uphill and close to a stream, raising a still more broad question of area contamination.

© Copyright 2012 InspectAPedia.com, All Rights Reserved. Information Accuracy & Bias Pledge is at below-left. Use page top links to major topics or use links at the left of each page to navigate within topics and documents at this website. Green links show where you are in a document series or at this website.

How to Think About Indoor Contaminants that Avoid Detection - Gases or Chemicals that do not Produce a Smell

Question About Indoor Chemical or Gas Hazards that Don't Smell

I am writing to ask you whether it is true that some chemicals are odorless. The reason for the question is that the smell seems to be dissipating. However, since we we do not know what the source of the smell was, we cannot know for sure whether the source causing the smell can still be harmful to our unborn baby. -- Jacqueline Saenz, CA.

Answer:

OPINION: Some chemicals are odorless - for example see "Fish Tale" in the New York Times. The article discussed a type of food poisoning (not a building material or sewer gas issue) associated with unsafe seafood - ciguatera poisoning (eating fish contaminated with a toxin that grown on reef algae) stating "Unlike most other causes of food poisoning, this toxin is colorless and odorless and isn't destroyed by cooking."

RADON HAZARD TESTS & MITIGATION
: if your building is over radon-bearing soils and rock, this odorless, colorless gas could be a health hazard. Testing and remediation are well understood and not technically difficult.

Similarly, carbon monoxide (CO) gas, (see CARBON MONOXIDE - CO) can be found in buildings where there is a gas burning appliance or chimney defect, is odorless and colorless.

But niether radon nor CO is ever smelly. So if there was an indoor odor present that later dissipated, it was not likely to be one of those particular hazards.

Because your original question (not included above) concerned sewer gas, it would be methane, not CO gas would have been more likely to be detected in your building. Sewer gas, a complex of gases, is not normally odorless. But sewer gas odors can indeed "come and go" depending on several variables, as we discuss below.

Building Indoor Odors / Smells that Eventually Diminish or Stop Completely

The types of building materials that smell for a while but then stop on their own, with no discover, repair, or removal of the offending source, include:

New building products - smells that dissipate and do not usually return, material, coatings, especially products that emit VOCs or other gases such as formaldehyde.

Examples of sources of indoor odors that typically diminish or stop entirely include some brands of carpeting, cabinets or shelving made from particle board, furniture (upholstered furniture using certain foam products and possibly even coverings such as a vinyl couch, glues used in applying tile or other ceiling or flooring products, some plywood products, rubber tub mats, sheet flooring (vinyl floors), paints, vinyl or rubber window curtains or shower curtains. We found a horrible building chemical smell traced to new 6-mil polyethylene plastic that had just been placed on the ground over a crawl space that extended below the structure. See these examples:

Building Odors / Smells That May Come and Go

Animal smells - odors from visiting animals may eventually dissipate after the pest or pet has been out of the building for weeks or months.
Heating Equipment, Age, Types, furnaces, boilers, water heaters, if there is a chimney cap or other venting defect, may make odors intermittently in buildings - for example stopping seasonally when the heater is not used. See BACKDRAFTING HEATING EQUIPMENT.
Sewer gases - odors from drains may come and go seasonally, or depending on fixture use. See SEWER GAS ODORS in COLD WEATHER.
Changes in building conditions can make even a long-lasting odor "come and go", including
- Variations in building indoor temperature and humidity
- Variations in weather, building leaks and moisture levels from outside conditions that affect the indoors
- Changes in building air movement: fans on or off, doors open or shut, windows open or shut, elevators in use or not, stairwells open or closed, different HVAC equipment in or out of use (heating vs cooling), cars running in a garage with a garage door open or shut (watch out for fatal carbon monoxide poisoning)

So How Might we Suspect and Decide to Test for an Odorless Gas or Chemical in Our Apartment?

Luckily, in most cases in buildings and building materials, problem chemicals or gases are delivered in a soup of materials, not in a pure form, and even if the dangerous material is odorless, most often it is in a soup that has an odor. For example, see BOILER NOISE SMOKE ODORS.

For example, carbon monoxide may be odorless, but if it's being delivered by a chimney leak or a car exhaust, other ingredients in those gases are often noticeable.

Watch out: often does not mean always. If building occupants are asleep during a CO poisoning hazard they could be asphyxiated without ever waking up. That is why it is really smart to have both working smoke detectors and working carbon monoxide detectors in your home.

How can I Check for or Test for Odorless Indoor Toxic Contaminants and Chemicals

OPINION: It is not cost-reasonable to try to test for every possible contaminant in a building, chemical or gas: there are just too many possibilities, and there not any simple inexpensive broad-spectrum "catch all" test. See TOXIC GAS TEST PROCEDURES. Don't just make a "wild guess" and then just test for that contaminant - doing so may lead to a false sense of security while you may be ignoring a problem that was not detected because it was not looked-for.

Make a Quick Amateur Do-it-yourself Building Contaminant Risk Assessment

Therefore our approach is to decide when further investigation or action is needed (do we need to "hire an expert") based on an initial level of risk assessment:

Are there building-related occupant complaints? This is a subjective measure but it can be helpful to know if people appear to react with IAQ or health or respiratory complaints when they enter or spend time in a specific building or building area.
Is there visible evidence of something thought to be a concern, some building condition or building event that often leads to an indoor environment or air quality worry, such as evidence of leaks, mold remediation (was the cleanup performed correctly) or a radon mitigation system (is it working properly?)
Is there history of leaks from any source that have wet building materials or cavities (possible hidden mold)
- A sewer backup (bacterial hazards) - see ODORS, SEPTIC or SEWER
- Unusual products, such as old chemical bottles
- Stains, spills that might need explanation
  - Mold Odors, Musty Smells in Buildings - may be suspected where leak stains mean ceilings or walls have been wet. At MOLD EXPERT, WHEN TO HIRE we describe how to decide if it's appropriate to hire a mold expert.
  - THERMAL TRACKING - indoor stains can indicate an unsafe heating system
Is there historical evidence that suggests a problem is highly likely though hidden
- A history of building use and building occupants may disclose prior activities that produced or used unsafe products or chemicals (gases? probably dissipated)
- A client bought a strip mall; we saw an abandoned trailer on the property - it had been used to store pesticides - turned out not to be a problem, as nothing had leaked;
  
  But later the client called to say that four owners back a tenant had done metal plating and there was heavy metal cadmium contamination in some of the soil - DEC wanted it cleaned up. No one dreamed this problem was lurking, but a more extensive historical research of building occupants and uses might have raised this question by identifying a metal plating operation years before.
Is there visual evidence that suggests a problem by "indirect evidence"

A client was buying a house; we saw evidence of a history of termite damage but no evidence of professional treatment (drill holes around the perimeter of the concrete floor slab that had been capped); we did see irregular, angled drill holes in floor framing near termite damage (possible unprofessional pesticide application); there was no record of professional pest control treatment; we took a sliver of wood from a sill plate for mailing to a test lab.

The lab confirmed that a now-banned pesticide, chlordane, had been liberally applied to wood surfaces. Possibly improperly. At a minimum, precautions during renovations were in order. If there is evidence of a specific concern, or type of concern, then further testing may be in order. If there is evidence of building related complaints, a visual inspection by an expert, combined with history taking about the occupants and the building, and possibly specific targeted tests, may be in order. See Pesticide Exposure Hazards.
Other examples of "indirect evidence" that can lead to important discoveries about conditions at a property are discussed at Developing Your X-Ray Vision

Other Building Hazards are Latent - Odorless, Colorless, Until an Event: Building Fire or Flood

Other indoor hazards are simply lurking, like a stair-fall: nothing happens until something else happens.

VINYL CHLORIDE HEALTH INFO discusses possible health concerns from PVC, dioxin, or HCL outgassing that occurs in vinyl building products (siding, windows, trim) are consumed in a fire (and possibly at lower levels from heating such as by sunlight).
Ozone Odors & Ozone "deodorizers" - sometimes misuse of this equipment actually creates a hazard indoors
See INDOOR AIR HAZARDS TABLE for a comprehensive list of indoor IAQ concerns

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ODORLESS CHEMICALS / GASES: CHECK FOR?

Thanks to reader Jacqueline Saenz for discussing concerns of both noticeable indoor odors and worry about remaining unsafe chemicals or products that do not smell. 4/12/2010
"Fish Tale", Diagnosis: Lisa sanders, MD, New York Times Sunday Times Magazine 4/11/2010, reported on a case of of ciguatera poisoning following consumption of contaminated barracuda shark flesh while visiting the Bahamas. The case was diagnosed by Dr. Kurtland Ma.
ASTM E2600 - 08 Standard Practice for Assessment of Vapor Intrusion into Structures on Property Involved in Real Estate Transactions is available from the ASTM at astm.org/Standards/E2600.htm .
"This practice is intended for use on a voluntary basis by parties who wish to conduct a VIA on a parcel of real estate, or more specifically conduct a screening evaluation to determine whether or not there is potential for a VIC, and if so, identify alternatives for further investigation."
The standard goes on to emphasize the uncertainty in testing any site for gases and vapor intrusion.
Developing your X-Ray Vision - 6th Ed. The Science of Building Inspections - advanced home inspection techniques including "The Limits of Vision," "Inattentional Blindness," "Invasive Inspection Methods," "Missed Defects," & "Contextual Inspection," "Termite Inspections," "Moisture & Building Water Entry," © Daniel Friedman 2006-1987
Carbon Dioxide Gas Toxicity hazard level, poisoning symptoms, & testing - you won't smell CO² (carbon dioxide) in a building, but if combustion gases from a heating or hot water system or possibly a wood stove or coal stove are not being safely vented to outdoors you may smell other telltale products of combustion.
Carbon Monoxide Gas Toxicity hazard levels, poisoning symptoms, & testing - you won't smell CO (carbon monoxide) in a building, but if combustion gases from a heating or hot water system or possibly a wood stove or coal stove are not being safely vented to outdoors you may smell other telltale products of combustion. Be certain that you have working CO detectors as well as smoke detectors in your building.
ODOR DIAGNOSIS CHECKLIST provides a checklist of places to look and things to do to track down the source of an odor or smell in building air, water, mechanical systems, heating, cooling, or other locations.
Gas Odors: A Toxic Gas Testing Sampling Plan for Residential Indoor Air Investigations. This document outlines gas toxicity levels and gas testing procedures we use in field IAQ and environmental health investigations for a range of indoor gases which may be produced by building product outgassing, mold and MVOCs, mechanical systems, fire damage, or contamination from nearby industrial, beauty parlor, dry cleaning, or other activities which often produce noxious or toxic odors and gases.
Gas Measurement Tools recommendations for selection and use of gas detection equipment and descriptions of how gas testing equipment is used
Gas Testing methods of screening for various odors, gases, and chemicals in the indoor environment
INDOOR AIR QUALITY IMPROVEMENT GUIDE - comprehensive "how to" articles
VINYL CHLORIDE HEALTH INFO - article series on dioxin and HCL hazards associated with vinyl building products: vinyl siding, trim, windows
SMELL PATCH TEST to Track Down Odors - a simple procedure using paper towels and aluminum foil can help track down a building odor to a specific surface indoors.

Books & Articles on Building & Environmental Inspection, Testing, Diagnosis, & Repair

Our recommended books about building & mechanical systems design, inspection, problem diagnosis, and repair, and about indoor environment and IAQ testing, diagnosis, and cleanup are at the InspectAPedia Bookstore. Also see our Book Reviews - InspectAPedia.
Environmental Health & Investigation Bibliography - our technical library on indoor air quality inspection, testing, laboratory procedures, forensic microscopy, etc.
Adkins and Adkins Dictionary of Roman Religion discusses Robigus, the Roman god of crop protection and the legendary progenitor of wheat rust fungus.
Kansas State University, department of plant pathology, extension plant pathology web page on wheat rust fungus: see http://www.oznet.ksu.edu/path-ext/factSheets/Wheat/Wheat%20Leaf%20Rust.asp
"A Brief Guide to Mold, Moisture, and Your Home", U.S. Environmental Protection Agency US EPA - includes basic advice for building owners, occupants, and mold cleanup operations. See http://www.epa.gov/mold/moldguide.htm
US EPA - Mold Remediation in Schools and Commercial Building [ copy on file as /sickhouse/EPA_Mold_Remediation_in_Schools.pdf ] - US EPA
US EPA - Una Breva Guia a Moho - Hongo [on file as /sickhouse/EPA_Moho_Guia_sp.pdf - - en Espanol

Allergies, Allergens, Allergy Testing in Buildings - References & Products

Air Conditioning System Blower Fans & Filters Cascading for Optimum Indoor Air Quality
Allergen Tests in Buildings advice about how to test, what to look for, in evaluating the level of dog, cat, or other animal allergens in a building
"IgG Food Allergy Testing by ELISA/EIA, What do they really tell us?" Sheryl B. Miller, MT (ASCP), PhD, Clinical Laboratory Director, Bastyr University Natural Health Clinic - ELISA testing accuracy: Here is an example of Miller's critique of ELISA http://www.betterhealthusa.com/public/282.cfm - Townsend Letter for Doctors and Patients
The critique included in that article raises compelling questions about IgG testing assays, which prompts our interest in actually screening for the presence of high levels of particles that could carry allergens - dog dander or cat dander in the case at hand.
http://www.tldp.com/issue/174/IgG%20Food%20Allergy.html contains similar criticism in another venue but interestingly by the same author, Sheryl Miller. Sheryl Miller, MT (ASCP), PhD, is an Immunologist and Associate Professor of Basic and Medical Sciences at Bastyr University in Bothell, Washington. She is also the Laboratory Director of the Bastyr Natural Health Clinic Laboratory.
Allergens: Testing for the level of exposure to animal allergens is discussed at http://www.animalhealthchannel.com/animalallergy/diagnosis.shtml (lab animal exposure study is interesting because it involves a higher exposure level in some cases
Allergens: WebMD discusses allergy tests for humans at webmd.com/allergies/allergy-tests
Animal Allergens: Dog, Cat, and Other Animal Dander - Cleanup & Prevention Information for Asthmatics and regarding Indoor Air Quality.
Atlas of Mold Related Illness Symptoms & Complaints - long list of both documented, studied mold related illness, and complaints ascribed to mold contamination or allergens in buildings
Cat Dander: how to inspect and test a building for past or current presence of cats, cat hair, cat dander, and cat allergens
Clinical Atlas of Mold Toxicity - An Online Description of Toxic, Pathogenic, Allergenic Fungi, Fungal Diseases
Fiberglass Insulation Contains Mold© 2005 comments about a field study in process, & more about health hazards from fiberglass insulation
Humidity: What indoor humidity should we maintain in order to avoid a mold problem?
Mold Action Guide detailed guide on finding, removing, and preventing indoor mold contamination
Odors, Odor Detection, Smells, & Gases how to find and identify sources of noxious or toxic odors and gases
Other environmental risks, Our much longer list: Asbestos, carbon monoxide, electromagnetic fields, etc.
Ozone: The Use of Ozone Indoors for Control of Odors and Mold Removal in Buildings: A Summary of Hazards and False Claims.
Pollen Allergens: identification, plant pollen and indoor air quality
Products to Reduce Mold & Allergy Problems to reduce indoor mold or allergen levels: air cleaners, air purifiers, dust mite covers, vacuum cleaners, crawl space vents
Recognizing Allergens: What various indoor allergens look like - identification photos to help identify pollen, dust mites, animal dander, toxic or allergenic mold - Common Mold and other Allergens, Irritants, Remedies & Advice
Rodent control issues, including dander, fecal, and urine contamination of Buildings and Building insulation are discussed at our
Sewage and Septic backup contamination in Buildings: inspection, testing, remediation, & references to expert sources
Action Guide: What to do about mold, mildew, and other indoor allergens
...

Mold Contamination Testing, Cleanup, Prevention: references & products

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
Aerobiology, Building Science, Microscopy, & Laboratory References, an extensive technical bibliography
Allergens: what they look like in buildings
Associations: Sick House, Sick Building, SBS - Air Quality, Government, Private Associations and Information Resources
Atlas of Clinical Fungi, 2nd Ed., GS deHoog, J Guarro, J Gene, & MJ Figueras, Centraalbureau voor Schimmelcultures, Universitat Rovira I Virgili, 2000, ISBN 90-70351-43-9 (you can buy this book at Amazon)
Atlas of Mold Related Illness: Index of Symptoms and health, physical, neurological, psychological, and other complaint which people suspect may be mold or building-related.
Atlas of Indoor Mold, Online Clinical Mold Atlas, Toxins, Pathogens, Allergens and Other Indoor Particles - Medical Health Effects of Mold (separate online document)
Black Mold that is Harmless Photos of recognizable, usually harmless black mold on wood, bluestain, ceratocystis, ophistoma
Building Floods: quick steps after a building flood or plumbing leak can prevent costly mold contamination
Classes of Mold: what types of cosmetic, allergenic, or toxic mold are a problem? Can mold be cleaned-up successfully?
Clinical Mold References - Detailed bibliography of mold reference texts
"A Brief Guide to Mold, Moisture, and Your Home", U.S. Environmental Protection Agency US EPA - includes basic advice for building owners, occupants, and mold cleanup operations. See http://www.epa.gov/mold/moldguide.htm
"Disease Prevention Program for Certain Vegetable Crops," David B. Langston, Jr., Extension Plant Pathologist - Vegetables, University of Georgia (PDF document) original source: www.reeis.usda.gov/web/crisprojectpages/209797.html
"Disease Prevention in Home Vegetable Gardens," Patricia Donald, Department of Plant Microbiology and Pathology, Lewis Jett
Department of Horticulture, University of Missouri Extension - extension.missouri.edu/publications/DisplayPub.aspx?P=G6202
"Management of Powdery Mildew, Leveillula taurica, in Greenhouse Peppers," Ministry of Agriculture and Lands, British Columbia - Original source: www.agf.gov.bc.ca/cropprot/peppermildew.htm
Environmental Health & Investigation Bibliography - our own technical library on indoor air quality inspection, testing, laboratory procedures, forensic microscopy, etc.
Fiberglass: Mold in Fiberglass Insulation© 2005 comments about a field study in process, & more about health hazards from fiberglass insulation - DJF
Fifth Kingdom, Bryce Kendrick, ISBN13: 9781585100224, is available from the InspectAPedia online bookstore - we recommend the CD-ROM version of this book. This 3rd/edition is a compact but comprehensive encyclopedia of all things mycological. Every aspect of the fungi, from aflatoxin to zppspores, with an accessible blend of verve and wit. The 24 chapters are filled with up-to-date information of classification, yeast, lichens, spore dispersal, allergies, ecology, genetics, plant pathology, predatory fungi, biological control, mutualistic symbioses with animals and plants, fungi as food, food spoilage and mycotoxins.
Fungi, Identifying Filamentous, A Clinical Laboratory Handbook, Guy St-Germain, Richard Summerbell, Star Publishing, 1996, ISBN 0-89863-177-7 (English) (buy at Amazon)
Looking for Mold Procedure: what mold is often found where in buildings - simple technical presentation
Meruliporia: the house eating fungus or "poria"
Mold Action Guide: Step-by-Step Instructions, What to do about mold, mildew, and other indoor allergens
MOLD APPEARANCE - WHAT MOLD LOOKS LIKE Photos of what mold looks like in buildings
MOLD APPEARANCE - STUFF THAT IS NOT MOLD Photos of NOT-mold material that is sometimes mistaken for mold
MOLD ATLAS & PARTICLES INDEX, Pathogens, Allergens and Other Indoor Particles - Medical Health Effects of Mold (separate online document)
MOLD BY MICROSCOPE Mold under the microscope - photo identification of the most common indoor molds found in buildings
Mold FAQs Answers to Most Questions about Indoor Mold, Mold Related Illness, Mold Cleanup, Mold Prevention
US EPA: Mold Remediation in Schools and Commercial Building [ copy on file as /sickhouse/EPA_Mold_Remediation_in_Schools.pdf ] - US EPA
Mold spores in the Home - a Photo ID Library for detection and identification of mold allergens
Mold Test Kits - How to Collect and Send Your Own Mold Sample to our mold testing lab or to any mold lab you wish
Most Common Indoor Molds Found in Buildings, A Table of
Mycology, Fundamentals of Diagnostic, Fran Fisher, Norma B. Cook, W.B. Saunders Co. 1998, ISBN 0-7216-5006-6 (buy this book at Amazon)
Ozone Warnings - Use of Ozone as a "mold" remedy is ineffective and may be dangerous.
Rot concerns in buildings-some building mold such as Meruliporia incrassata "Poria" risks serious rot and hidden structural damage
US EPA: Una Breva Guia a Moho - Hongo [on file as /sickhouse/EPA_Moho_Guia_sp.pdf - - en Espanol

OTHER IAQ ISSUES: How To Find and Address Other Indoor Air or Indoor Environment Contaminants Besides Mold

Mold or allergens may not be the only or even the main indoor environmental contaminant. Don't let media attention to mold cause so much enviro-scare fear that other, possibly more urgent hazards go un-addressed.

Fiberglass building insulation and HVAC duct work insulation hazards
Sewage and Septic backup contamination in buildings: inspection, testing, remediation, & references to expert sources
Other environmental risks: Asbestos, carbon monoxide, electromagnetic fields, environmental illness, fiberglass, MCS - multiple chemical sensitivity, toxic gases, etc
Indoor Gas Sampling Plan for Residential Buildings lists a number of toxic indoor gases which we test for, depending on the building complaint and building conditions
Ozone Warnings - Use of Ozone as a "mold" remedy is ineffective and may be dangerous.
Pet control - if you can't say goodbye to your bird, cat, dog, guinea pig, hamster, tropical fish, then limit the areas they occupy and limit the airflow from that area to sleeping or other areas of the building, use allergenic bedding, eliminate wall-to-wall carpeting, improve housecleaning including use of a HEPA-rated vacuum cleaner. For more details see our article Dog, Cat, and Other Animal Dander - Information for Asthmatics and Indoor Air Quality
Rodents, Mice, Squirrel Control - I find high levels of mouse and rodent dander, fecal dust, and urine-contaminated dust in some buildings, and high levels of these materials in building insulation in those locations. If you have a mouse problem, particularly if mice and their waste (fecals or urine) are contaminating the building HVAC or building insulation, may need both steps to clean up or remove infected materials and steps to stop an ongoing rodent problem. If squirrels are a problem, the cleanup needs to include closing off entry openings into the building. Get some help from a licensed pest control expert.

Free Encyclopedia of Building & Environmental Inspection, Testing, Diagnosis, Repair

Ask a Question or Search InspectAPedia

How to Think About Indoor Contaminants that Avoid Detection - Gases or Chemicals that do not Produce a Smell

Building Indoor Odors / Smells that Eventually Diminish or Stop Completely

Building Odors / Smells That May Come and Go

So How Might we Suspect and Decide to Test for an Odorless Gas or Chemical in Our Apartment?

How can I Check for or Test for Odorless Indoor Toxic Contaminants and Chemicals

Make a Quick Amateur Do-it-yourself Building Contaminant Risk Assessment

Other Building Hazards are Latent - Odorless, Colorless, Until an Event: Building Fire or Flood

Questions & Answers regarding this article

Ask a Question or Search InspectAPedia

Technical Reviewers & References

ODORLESS CHEMICALS / GASES: CHECK FOR?

Books & Articles on Building & Environmental Inspection, Testing, Diagnosis, & Repair

Allergies, Allergens, Allergy Testing in Buildings - References & Products

Mold Contamination Testing, Cleanup, Prevention: references & products

OTHER IAQ ISSUES: How To Find and Address Other Indoor Air or Indoor Environment Contaminants Besides Mold