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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 MOLD / ODOR TREATMENT WARNINGS
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
STAINS on CONCRETE
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
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 meandfering in daylight. This skunk was found dead two days after this photo was taken, most likely due to rabies. .
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At left the author demonstrates a smell-patch test that can be used to track down odors to their source in buildings.
You can start tracking down the cause or source of an odor in one or more of several ways:
Checklist of Places to Look & Things to Do to Track Down an Odor to it Source
Here are some possible sources of an odor or smell in building air, water, mechanical systems, heating, cooling, or other locations.
Continue reading at ODOR DIAGNOSIS SIX STEPS or select a topic from the More Reading links shown below.
Suggested citation for this web page
Green link shows where you are in this article series.
Frequently Asked Questions (FAQs)
Question: Sweet / Fume type smell in a two story house
For the past three weeks my father has had a sweet/fume type smell in his two story house. The odor is concentrated in his bedroom. Professionals have come out to clean the air vent/ducts, the carpet cleaned, home inspector etc. and have not been able to determine the source of the odor. He has open all the windows, run the heat any and everything suggested nothing has worked. He has had to throw furniture, bedding etc. away because of the odor. The odor has gotten so bad he is unable to live in the house.
The service people who have been to the house have no clue and also aren't able to direct us how to determine what the problem is and how to fix it. Environmental companies said they need to know specifically what they are testing for such as mold etc. There is no construction going on in the area. He is at his wits end. He lives in Houston, TX. Any assistance anyone can provide would be greatly appreciated. - T. Wilson 8/7/11
Reply: distinguish between sweet fumes and mold odors
Please seeODOR DIAGNOSIS SIX STEPS for more help.
Question: musty odor through interior partition wall, worse in damp or rainy weather; high VOCs at kitchen drain; possible sewer gas odors
I have a musty odour coming from the wall that separates my kitchen and living room which worsens when it is damp, rainy, there is no heat on or the AC unit is running. An environmental inspector did an AQ test for mold from the electrical outlet on the living room side, where the odour was quite strong but the results showed very low concentrations of mold spores compared to outside. T
he inspector also used a PPB Rae to measure volatile organic compounds at the kitchen drain which showed extremely elevated levels of VOC's between 35000 to 83000 ppb when initially operating the water. The numbers dropped significantly after the water had been running. The conclusion of the inspector was that plumbing is likely to need repair in the wall cavity and potentially the main trap at the entrance to the building.
Would a camera inspection be able to show if there is a problem in the wall cavity or should the wall be opened up? I have concerns about the latter because of the possibility of contamination from whatever is causing the musty odour. I have smelled sewer gas on at least two occasions, first under the kitchen sink and the second time in the electrical outlet on the living room side. Thanks! - Denise 1/13/12
Recently my neighbor has done some extreme excavating, removing two home and making a parking lot. I have at times noticed an extremely awful smell in my basement(rotten sauerkraut), I think it is sewer gases, but how do i check. City sewer line I am the next to last home on the line. I have had severs head aces nausea, not all the time,I don't have much money for a lot of testing, who do I call? - Beth firstname.lastname@example.org 4/10/12
Watch out: Beth, since you are describing possible damage to and potentially dangerous (explosive) leaks from a public sewer, you should call your city building department promptly to describe the odor, and construction, and worry about what might be a dangerous sewer gas leak.
Denise, running HVAC equipment, fans, or even changes in how windows or doors are open or shut, or changes in indoor or outdoor temperature and similar conditions or changes all affect how air moves in buildings. In cases of enough negative pressure indoors (rising air currents, running exhaust or whole house fans, for example), these can cause backdrafting out of building drains - a condition that is made worse if drains are not properly vented or if the vents are blocked.
I'm not sure what sense it makes to measure VOCs at a building sink drain. I have never measured a sink or tub drain in a building that had seen use that did not cause the instrument to respond - the contents of traps are often a bit smelly on close inspection. On the other hand, dry traps, or traps that are siphoned dry during plumbing system use, or defective or blocked building vent piping can be a serious, even dangerous source of sewer gases. Some odors traced to building walls were in fact traced to openings in a vent piping system in the wall.
Question: dirt floor smells over possible outhouse location
We live on a farm it has a double garage open front dirt floor. on the back is a small area which i think was a old drop hole toilet witch is filled in and open to shed . when you walk past or go in shed there is a very strong smell of sewage . what can be put on the dirt to get rid of smell thanks - Bernie 2/25/12
Reply: use an impermeable membrane below the soil to reduce odors in a shed over an old outhouse pit
Bernie, indeed the soil where an outhouse previously stood can continue to hold concentrations of waste for years because of the concentration of sewage with comparatively low water content, deep in the soil where there is a lack of aerobic bacteria, and probably because often lime was added to control odors, also preserving the waste from bacterial action. Usually, where the soil is open to the air outdoors it's not a source of complaints if it was buried with several feet or more of clean fill.
But in a shed or enclosure odors from gases passing out of the soil may indeed be a problem. I would not try treating the dirt itself with any chemical or deodorant - not only will it probably not work, it may simply be a new contaminant. You might find success by removing a top layer of soil, installing an impermeable membrane (rubber EPDM roofing would work, or a plastic intended for soil burial such as sold by geotextile and foundation waterproofing manufacturers), and burying that layer again with soil.
Question: oil fume odor complaints
(Mar 13, 2014) nameless said:
we have been breathing in furnace oil fumes for over a month . found out there was a leak. there is oil laying in a drip pan as well as in the ground and on the tank. worried about health issues for myself n son. as i am renting i have no control over the situation except to keep complaining or move which im not in the financial position to do.
Please search InspectApedia for the article titled
Crude Oil & Heating Oil Exposure Effects, Exposure Limits, Health Hazards
and you can read information that answers your concern and includes authoritative citations.
About financial constraints, that's a concern too, but one you may best want to bring to your local aid associations in your home town, county, state or province.
Question: Multiple chemical sensitivity from mold, VOC sensitivity
(Mar 17, 2014) joseph williams said:
my35 year old daughter and husband bought a modular home 2 years ago. she has now gone from slight case of multiple chemical sensitivity from mold in their first house. and moved into a modular home, now 12 years old has caused her sensitivity to any voc producing products that she is not able to spend more than a few minutes in the house before starts reacting with nausea and headaches. for the past year, she and her husband (he is not affected) live in an outdoor shed. a series of air quality tests last year showed very high levels of multiple chemicals including very high amounts of formaldehyde. they got rid of all furniture, had all carpet and padding removed, only furniture left in house is their bed they can't use.
They have no heating system in place because the propane made her sick. she wears a triple filtered face mask over her nose and down to her chin when entering the house. selling the house is not an option. plus she can not get near husband coming home from work until he showers and bags all his clothes and changes. there seems to be no solution on the horizon. Is there any way they could legally get out of the mortgage from her severe health concerns?
Joseph, I'm sorry to read of the health concerns you describe, but this is a legal question not one for a building diagnostician. Your daughter and husband will want to discuss their concerns with their bank and if necessary with their attorney.
I caution that for someone suffering from MCS bailing out of a home, ruining one's credit, undergoing legal and financial stress around that topic, may be only jumping from the frying pan into the fire so to speak: that is, how do we know in advance that the new home will be less problematic than the current one?
Question: propane odor under the kitchen sink
(Apr 10, 2014) Bill said:
There is a propane odor beneath our kitchen sink, but we are not hooked up to natural gas and don't use propane in the house for anything. Can it be caused by a mouse nest?
Question: odor problems at work, winter weather
(May 29, 2014) Sarah Edwards said:
We have recently started having a odor problem at work. It started a few months ago roughly January February time frame. It happens almost daily and just once a day. It is random as to when in the day it will occur. Sometimes we come in to open up and it smells and then other days it will just pop up at different times of the day. We have one bathroom with a toilet and sink, there are no apparent leaks.
The smell is throughout the entire building (not a big building) but is most pungent in the office that shares a wall with the bathroom. The smell is most like rotten eggs and poop. When it starts it is very strong and burns your nose but after a little while you get used to it until you walk outside and come back in. We have had plumbers check and they said everything is fine, we had the a/c drains flushed out to no avail. What could it be and what should we do to identify and remedy this odor, we are having many complaints from customers about it.
I'm not sure but suspect a plumbing vent leak or a sewer line leak somewhere. Those can be hard to track down if there is no actual water or sewage leak to leave a stain - for example a leak in a dry vent stack pipe. Flushing drains won't fix such a problem if it's coming from sewer gases leaking back up into the building.
As the odor started recently, ask what changed in the building, occupancy, use, weather, etc.
Keeping an odor log might help track down the source too.
Ultimately people track to odor to strongest location and if a drain is suspected, start by inspecting the actual drain, then the vent piping. We've found hidden sewer gas leaks in vent pipes in walls, for example.
Also search InspectApedia for "rotten egg smell sources" for diagnostic help
Question: work place odors in shopping mall - traced to plumbing vent?
(May 31, 2014) HAPPY FEET said:
We have this smell problem in my workplace building, a shopping mall. This happened after the reconfiguration of a few retail units at Level 3. There is an additional floor trap created for the Tenant. The Techician checked their floor traps and vent pipes. No smell from the floor traps. The vent pipes were already capped. All seem well. The smell is discribed as foul smell and its in the air.
The techician went to inspec the common area riser and found the vent pipe stack to be in order. Not sure where coud be the possible source of foul smell. Please help! Thanks alot
at this article are links to procedures that may help you, articles titled
I'm not sure what inspection was made of the vent piping (there can be a leak in a hidden building cavity or space), nor what the heck is meant by "the vent pipes were already capped" - capping off vent pipes where venting is in fact required could cause drainage problems as well as loss of water in plumbing traps, leading to sewer gas odors.
(June 11, 2014) Angela said:
We have totally refinished a room with serious cat pee odor in one room of our new house...new walls, carpets removed, refinished hardwood floors and the odor is still horrible, especially on humid days...ugh...please help!
(June 20, 2014) Sandra said:
I have an intermittent earthy smell in my bathroom, all drains smell clean.
7/31/14 Lenda said:
Toxic odor definitely traced to fiberglass panels installed in my basement 4 months ago, very strong, 5minutes of exposure
Lenda, if you indeed confirmed that a gas that's the source of an odor in your basement is "toxic" then you've answered your own question.
Generally one would identify and remove the odor source.
Question: urine odors in laundry, washing machine, other confusion
8/3/14 Lori said:
We had the roof replaced july. In november our newly washed clothes smelled like urine. By december we had rotated most clothes and our walk in closet smelled like urine. One morning inturned on the wash machine while husband was in the shower. He said heavy sewage smell rose from drain. I cleaned and scrubbed wash machine 3-4 times with all products suggested online. Washer repairman said machine was not the problem. He thought it was the water that was stinky. He replace hoses. Our plumber was no help at all. We did not have the urine smell anywhere else in the house except where washed clothing, towels, etc. were placed. We thought a plugged vent on the roof but our plumber won't look.
If the ONLY place the water supply smells is at the washing machine then the odor source would be there - e.g. perhaps from a cross connection, sewage backup, bacterial contamination, or dead animal in or under the washer or cat peeing therein, etc.
When sewage smells emanate from a drain I suspect improper, missing, or clogged plumbing vents, possibly combined with a partial drain blockage.
See Urine odors & smells from animals, humans, other sources at ANIMAL or URINE ODOR SOURCE DETECTION
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