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ODORS GASES SMELLS, DIAGNOSIS & CURE
AIR POLLUTANTS, COMMON INDOOR
AIR QUALITY IMPROVEMENT STRATEGIES
BOOK MOLD, Moldy Book Cleaning
CAR MOLD CONTAMINATION
CAT DANDER in buildings
CHEMICAL CONTAMINANTS in WATER
CHEMICAL ODOR SOURCES
CHLORINE IN DRINKING WATER
COMBUSTION GASES & PARTICLE HAZARDS
DIRT FLOOR MOLD CONTAMINATION
DUCT SYSTEM & DUCT DEFECTS
EMERGENCY RESPONSE, IAQ, GAS, MOLD
Fireplaces & Woodstove Contaminants
FLOOD DAMAGE ASSESSMENT, SAFETY & CLEANUP
GASES, EXPOSURE, TESTING
GAS DETECTION INSTRUMENTS
GAS EXPOSURE LIMITS & STANDARDS
GLUES ADHESIVES, EXTERIOR CONSTRUCTION
HEATING OIL EXPOSURE HAZARDS, LIMITS
INDOOR AIR HAZARDS TABLE
INDOOR AIR QUALITY & HOUSE TIGHTNESS
INDOOR AIR QUALITY IMPROVEMENT GUIDE
LIGHT, GUIDE to FORENSIC USE
GAS LP & NATURAL GAS SAFETY HAZARDS
METHANE GAS SOURCES
MILDEW in BUILDINGS ?
MOISTURE CONTROL in BUILDINGS
MOLD ACTION GUIDE - WHAT TO DO ABOUT MOLD
MOTHS, MOTHBALL ODORS
MSDS Material Safety Data Sheets
MVOCs & MOLDY MUSTY ODORS
ODORS GASES SMELLS, DIAGNOSIS & CURE
OIL, HEATING, EXPOSURE HAZARDS, LIMITS
OIL HEAT ODORS & NOISES
OIL TANK LEAK & ODOR CAUSES
OIL ODOR SOURCES
OUTHOUSES & LATRINES
OZONE for MOLD OR ODORS
PET ALLERGENS / PET DANDER
PET STAINS & MARKS in BUILDINGS
PET STAINS on WALLS
SEPTIC SYSTEM ODORS
SEPTIC TREATMENTS & CHEMICALS
STAINS on & in BUILDINGS, CAUSES & CURES
STAIN DIAGNOSIS on BUILDING EXTERIORS
STAIN DIAGNOSIS on BUILDING INTERIORS
THERMAL IMAGING MOLD SCANS
UREA FORMALDEHYDE FOAM INSULATION, UFFI
URETHANE FOAM Deterioration, Outgassing
VENTILATION in BUILDINGS
VINYL CHLORIDE HEALTH INFO
VINYL Siding or Window PLASTIC ODORS
VOCs VOLATILE ORGANIC COMPOUNDS
WATER TEST CHOICES & WATER TEST FEES
WATER TREATMENT EQUIPMENT CHOICES
Six-step procedure to track down the source or cause of odors or smells in or around buildings. Here we describe six areas of investigation that can help direct the inquiry as to the cause or source of an odor or smell in or around a building.
These articles explain how to diagnose, test, identify, and cure or remove a wide range of obnoxious or even toxic odors in buildings, in building air, in building materials, or in the 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, indoor mold odors, oil tanks or oil spills, pesticides, septic odors, sewer gases, and even abandoned chemicals at properties. Our page top photo shows our local skunk rummaging on a nearby golf course. This is about as close as you want to be, especially if you see a skunk meandering in daylight. This skunk was found dead two days after this photo was taken, most likely due to rabies. .
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The photo at left 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.
Hire an Inspector or Consultant vs Do-It-Yourself?
A competent onsite inspection by an expert usually finds additional clues that help accurately diagnose a problem such as this one. It is a frequent frustration to discuss with readers and clients the common experience of hiring a costly investigator or hygienist to help with a problem only to find that that expert does the easy part - conducting a few (sometimes unreliable) sample collections, sends them to a lab and gives you a report. Such tests alone, without a translation into sufficient diagnosis as to permit action, are of limited use.
You can start tracking down the cause or source of an odor in one or more of several ways:
Six Steps to Track Down the Source of a Building Smell
1. Try odor source tracking: try the SMELL PATCH TEST to Track Down Odors method to see if you can isolate the odor to a particular surface. It's cheap, easy, and can sometimes give dramatic results. When I refined and field tested this method, first suggested to me by Jeff May (Cambridge MA), the person we used as the "smeller" was in fact a pregnant woman whose sense of smell was reported to be particularly sensitive.
At left the author demonstrates a smell-patch test that can be used to track down odors to their source in buildings.
2. List building and building condition factors causing odors: at ODOR DIAGNOSIS CHECKLIST, PROCEDURE we give a procedural checklist that can help track down the source of an odor by reviewing a laundry-list of types of odors, odor sources, and building and even weather conditions that can be diagnostic. Just as one example we've tracked certain odors to plastic windows or window screens that emitted smells principally after some time in direct sunlight.
If you suspect sunlight related odor emission note:
3. List & investigate building history, materials, location: in the odor checklist cited at item 2 we provide examples of building history that can point to a particular odor source. Add some more detailed considerations such as
4. Use surface testing to confirm an odor source: best performed after we have some most-suspect surfaces in mind, it may be possible to collect and send a small physical sample to an appropriate test lab for confirmation of what we're looking at.
For example, at a home where I suspected amateur application of pesticide (chlordane), I cut a small sliver of wood that we sent to an independent test lab (my lab specializes in particle forensics not chemicals) who confirmed that the wood had indeed been soaked with pesticide.
5. Temporarily Contain odors & smell-related risks: if odors appear to originate in just a single room in a building, temporarily, try keeping the offending room's door shut and are minimizing exposure to risk.
Watch out: for odor desensitization: anyone who remains in an area where odor-producing substances are present, eventually becomes desensitized to the odors and can be thus fooled into thinking that the odor is not present or has been diminished. A good test is to consider how things "smell" to you or others on entering the condo just after you've spent hours or longer out in fresh air.
6. Remediation of odors or smells: don't do anything expensive or disruptive towards a "cure" before you have a reasonably confident idea of what the problem is..
At ODORS GASES SMELLS, DIAGNOSIS & CURE we list many sources of odors & smells in buildings - the list itself may suggest some candidates for you that can help tracking down your own complaint.
Separately at ODOR DIAGNOSIS CHECKLIST, PROCEDURE we offer a procedural checklist that can help in tracking down an odor
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Frequently Asked Questions (FAQs)
Question: We tried the obvious, now how can we track down the source of a smell in our home?
I have a 4 year old brick home, on basement, 1 story. I have smelled a faint odor in one area of the home which is around the master bedroom, master bath, and hallway leading to that area.
The smell tends to be stronger in the hallway area which is on the other side of the wall from the bathroom. My husband does not smell it and thinks I am crazy. Some days is it stronger than others but I can't figure out why. The smell is not in the basement, and not in the attic.
We replaced the toilet wax ring, with no results. We put a vent cap on the roof vent of the toilet so that wind would not blow the gases back inside, with no results.
How can I track down the smell? My only other ideas are that the roof has leaked and the wall has molded, or there is a problem with the bathroom fan leaking in foul air. Or a dead animal stuck somewhere in the wall.
Desperate for some fresh air,- J.H.
See our odor diagnosis procedural checklist at ODOR DIAGNOSIS CHECKLIST, PROCEDUREor review the six-step approach to odor diagnosis described in the FAQ just below.
A competent onsite inspection by an expert usually finds additional clues that help accurately diagnose a problem or source of an odor. That said, It is an error for someone to assume that because they do not personally smell an odor that it is not present. Individual sense of smell varies widely among individuals. However on occasion there are medical or other sources of perceived odors that only the affected person will experience. Therefore in some cases it may be appropriate to also check in with a physician. But it makes sense to look for the obvious: an actual source of odors or smells in the building.
Reader Question: confusing odors in home
I am in England, UK and cannot afford to pay for advice. If you can give me any help with my situation I'd be grateful:
I am experiencing an overpowering 'electrical burning' odour in my bathroom. There is no obvious problem with the electrics. Electrics switched off and room ventilated/flushed out but smell continues. The bath is old cast iron, with damaged enamel and a lead waste pipe. I have used limescale removing chemicals (some weeks ago) and bleach (two days ago). There is no blockage in the drain. There is green algae/weed growing outside at the end of the lead pipe as it hangs over and empties into the storm water (not foul water) drain system. Advice asap most appreciated. Currently waiting emergency plumber on household insurance. - A.G. 3/4/2014
I'd like to help Amanda but I have to say that from your description you need someone on-site.
Your description of odor includes
And of course there could be a different odor source that has not yet been realised. Some help in identifying the odor and its source, perhaps by asking for assistance from others or from your plumber is what's needed along with a visual inspection for safety and sanitary concerns in your home. It may help to try the six simple odor diagnostic steps in the article above on this page, or to try our more detailed ODOR DIAGNOSIS CHECKLIST, PROCEDURE.
Questions & answers on how to identify the source of smells or odors in buildings - an odor source checklist.
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