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ODORS GASES SMELLS, DIAGNOSIS & CURE
AIR POLLUTANTS, COMMON INDOOR
AIR QUALITY IMPROVEMENT STRATEGIES
ALLERGEN TESTS for BUILDINGS
ANIMAL or URINE ODOR SOURCE DETECTION
BACKDRAFTING HEATING EQUIPMENT AQ
BIOGAS PRODUCTION & USE
BOOKSTORE - ENVIRONMENTAL
CARPETING & INDOOR AIR QUALITY
CHINESE DRYWALL HAZARDS
CHEMICAL CONTAMINANTS in WATER
COMBUSTION GASES & PARTICLE HAZARDS
DIRECTORY of MOLD / ENVIRONMENTAL EXPERTS
DISINFECTING BUILDINGS with BLEACH
DRYWALL MOLD TESTING
DUCT SYSTEM & DUCT DEFECTS
DUST SAMPLING PROCEDURE
EMERGENCY RESPONSE, IAQ, GAS, MOLD
FLOOD DAMAGE ASSESSMENT, SAFETY & CLEANUP
GASES, EXPOSURE, TESTING
GAS DETECTION INSTRUMENTS
GAS EXPOSURE LIMITS & STANDARDS
INDOOR AIR QUALITY & HOUSE TIGHTNESS
INDOOR AIR QUALITY IMPROVEMENT GUIDE
INDOOR AIR QUALITY METHODS COMPARED
LIGHT, GUIDE to FORENSIC USE
GAS LP & NATURAL GAS SAFETY HAZARDS
Legionella Legionnaires' Disease
METHANE GAS SOURCES
MILDEW in BUILDINGS ?
MOISTURE CONTROL in BUILDINGS
MOLD: A COMPLETE GUIDE to TEST CLEAN PREVENT
MOLD ACTION GUIDE - WHAT TO DO ABOUT MOLD
MOLD EXPERT, WHEN TO HIRE
MOLD or INDOOR AIR EMERGENCY RESPONSE
TEST KITS for DUST, MOLD, PARTICLE TESTS
MVOCs & MOLDY MUSTY ODORS
ODORS GASES SMELLS, DIAGNOSIS & CURE
OUTHOUSES & LATRINES
OZONE for MOLD OR ODORS
PLUMBING SYSTEM ODORS
SEPTIC & CESSPOOL SAFETY
SEPTIC SYSTEM ODORS
SEPTIC TREATMENTS & CHEMICALS
SEWAGE & SEPTIC CONTAMINANTS
SEWAGE CONTAMINATION in BUILDINGS
SEWAGE EJECTOR / GRINDER PUMPS
SEWAGE PATHOGENS in SEPTIC SLUDGE
SEWAGE BACKUP, WHAT TO DO
SEWAGE BACKUP TEST & CLEANUP
SEWER GAS ODORS
SEWER LINE REPLACEMENT
SMELL PATCH TEST to Track Down Odors
STAIN & BIODETERIORATION AGENT CATALOG
STAINS on & in BUILDINGS, CAUSES & CURES
SULPHUR & SEWER GAS SMELL SOURCES
THERMAL IMAGING MOLD SCANS
UV LIGHT BLACK LIGHT USES
VENTILATION in BUILDINGS
VOCs VOLATILE ORGANIC COMPOUNDS
WASTEWATER TREATMENT BASICS
WATER ODORS, CAUSE CURE
WATER TESTS, CONTAMINANTS, TREATMENT
WATER TEST CHOICES & WATER TEST FEES
WATER TREATMENT EQUIPMENT CHOICES
WATER, WELLS, WATER TANKS: TESTING GUIDE
WETLAND SEPTIC SYSTEMS
Hydrogen sulfide (H2S) gas sources in buildings: don't overlook these possible sources of sewer gas smells or hydrogen sulfide gas odors: here are the causes, sources, & cures for often overlooked sources of sewer gas smells. This article series explains how to diagnose, find, and cure odors in buildings including septic or sewage or sewer gas smells or "gas odors" in buildings.
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Watch out: both hydrogen sulfide gas and methane gas (both present in sewer gases) are potentially explosive. In addition, exposure to high levels of these gases can be harmful, even fatal, as we detail below.
Because sewer gas contains methane gas (CH4) there is a risk of an explosion hazard or even fatal asphyxiation. Sewer gases also probably contain hydrogen sulfide gas (H2S) In addition some writers opine that there are possible health hazards from sewer gas exposure, such as a bacterial infection of the sinuses (which can occur due to any sinus irritation). Hydrogen is extremely flammable (easily set fire or explodes).
Depending on the sewer gas source and other factors such as humidity and building and weather conditions, mold spores may also be present in sewer gases.
Septic system odors or sulphur odors may be hydrogen sulfide (H2S) and may occur from these conditions which you may not have considered.
Watch out: both hydrogen sulfide gas and methane gas (both present in sewer gases) are potentially explosive. Hydrogen sulfide gas is heavier than air, poisonous, corrosive, flammable (will burn), and depending on its concentration in air, it can explode.
My older sister Linda and later my best friend David Hoff both led experiments in attempts to light ... well, politely put, human flatulence gases. Results were amazing. But in buildings an accumulation of hydrogen sulfide gas H2S is not funny, it is potentially catastrophic, or fatal should an explosion occur. In dangerous mixtures with air or if put into direct contact with nitric acid, H2S explodes. (Fletcher 1999)
The following information about hydrogen sulfide gas H2S hazards is adapted from information from U.S. Army Field Manual 8-285 Chapter 10, Noxious Chemicals:
10-4. Hydrogen Sulfide Gas Danger Information
Physical Properties of Hydrogen Sulfide Gas:
This colorless gas in low concentrations has the odor of rotten eggs. In high concentrations it may dull the sense of smell and be difficult to recognize.
Occurrence of hydrogen sulfide gas in military operations. This gas is produced during the decomposition of sulfur containing compounds in sewers, waste, coal bins or stacks, holds of ships, and waterfront excavations.
Occurrence of hydrogen sulfide gas in Military Operations as well as in civilian and residential conditions
Hydrogen sulfide gas is produced during the decomposition of sulfur containing compounds in sewers, waste, coal bins
Pathology of Hydrogen Sulfide Gas Exposure
In low concentrations (less than
0.15 mg per liter), hydrogen sulfide may produce
inflammation of the eyes, nose, and throat if breathed
for periods of 1/2 to 1 hour.
Watch out: higher concentrations of hydrogen sulfide (H2S) gas (0.75 mg per liter or greater) are rapidly fatal, presumably by combination of the hydrogen sulfide with the respiratory tissue pigments and the subsequent paralysis of the respiratory center.
Symptoms of Hydrogen Sulfide Gas Exposure
The symptoms depend upon the concentration of the gas. At the lowest concentrations, the effects are chiefly on the eyes; that is, conjunctivitis, swollen eyelids, itchiness, smarting, pain, photophobia, and blurring of vision. At higher concentrations, respiratory tract symptoms are more pronounced. Rhinitis, pharyngitis, laryngitis, and bronchitis may occur. Pulmonary edema may result. At very high concentrations, unconsciousness, convulsions, and cessation of respiration rapidly develop.
Details about H2S exposure effects & limits are at
Treatment for Hydrogen Sulfide Gas Exposure
Immediately remove the casualty from the contaminated atmosphere and administer assisted ventilation with oxygen, if possible. Treatment of pulmonary edema is the same as for that caused by CG (chap 5).
Reader Comment: Hydrogen Sulfide Gas H2S health hazards warning & citation of HUD Dictionary of Deficiency Definitions
Not a question just a comment.
HUD regulates how to keep those in living in subsidized housing from the dangers of sewer gas inhalation but the state of Georgia (Georgia Dept. of Community Affairs a HUD area housing administrator) does not follow that HUD mandate and that is why myself and my child have severe lung disease that is caused from our prolonged exposure to sewer gas within and about a Bremen, GA rental.
- SB4Justice - 4/4/2013
Thanks I've posted your remark above so that I could include a link to the Hud Deficiencies Definitions document provided by U.S. HUD.
Details about methane gas hazards are given separately at METHANE GAS, SEPTIC / SEWER.
Watch out: while H2S can be dangerous, readers should keep in mind that both H2S and more commonly methane gas (a significant component in sewer gas) is dangerously explosive and at sufficient concentrations can also be fatal. So both can be an immediate hazard, not just a health hazard.
The same HUD Deficiencies document you cite, back up on page 304 also warns:
And from HUD Pass/Fail deficiencies p. 302 we have more general advice
Which is in error only that mildew is never found in buildings, only mold, unless the mildew is growing on a plant (my photo at left). Mildew is an obligate parasite that only grows on plants. Of course normal people don't know that and the word "mildew" is used by lay persons interchangeably (if incorrectly) with "mold". Details are at MILDEW in BUILDINGS ?
Thank you again SB4Justice for pointing out these dangers. Working together we're smarter. - Daniel F.
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