Toxic gas exposure in buildings: gases, allowable exposure limits, gas detection, gas source track-down & cure. Effects of Toxic Gas Exposure to Ammonia, Arsine, Arsenic, Bromine, Carbon Dioxide, Carbon Monoxide, flue gases, heating equipment exhaust gases, Hydride, as well as odors & smells.
InspectAPedia
Free Encyclopedia of Building & Environmental Inspection, Testing, Diagnosis, Repair
Effects of Toxic Gas Exposure in buildings
Toxic gas exposure limits & standards in buildings
- CONTENTS: Effects of exposure to various gases that may occur in buildings, including
Ammonia, Arsine, Arsenic, Bromine, Carbon Dioxide, Carbon Monoxide, Hydride, Hydrogen Sulfide, Nitrogen Oxide Gas, Propylene, Propane, LP gas Sewer Gas, Sulphur dioxide, & others
the toxicity of various gases found in buildings
InspectAPedia tolerates no conflicts of interest. We have no relationship with advertisers, products, or services discussed at this website.
What are the effects on humans of exposure to various toxic gases that are found in buildings?
This document gives basic information about exposure to and potential
health hazards from a number of common toxic gases that may be found indoors or in or around buildings. We describe symptoms of exposure to these gases, industry recommendations for gas exposure limits, how gases may be measured, and how to track down and cure the sources of gas leaks in buildings.
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Potential Health Hazards of Exposure to Certain Gases
Portions of this material are quoted from comments by
at a public CompuServe safety forum in 1989.
Gas exposure hazard evaluation consists of comparing measurements of exposure (or dose) with exposures (doses) known to be safe or
known to be hazardous.
For the most part, because of biological variation, &no effect& levels are much easier
to estimate than are &first effect& or other levels indicative of injury.
Watch out: When considering the possible toxicity or health hazards of exposure to gases in buildings, readers should note that
Individual
sensitivity and potential health effects on individuals may vary widely and
There may be multiple (un-cited) recommended or allowable exposure limits
coming from various sources.
We have seen wide variation in allowable exposure
limits, for example, for Carbon Monoxide permissible exposure limits -(CO PELs).
Of the several industrial
hygiene standards-setting groups in this country, the most important and/or most quoted are the National Institute
for Occupational Safety and Health (NIOSH), the Occupational Safety and Health Administration (OSHA), and the American
Conference of Governmental Industrial Hygienists (ACGIH).
Only those standards promulgated by OSHA (called Permissible
Exposure Limits or PELs) h the others are advisory except that OSHA has claimed the power to force
compliance with NIOSH &Recommended Standards& if it chooses to do so.
The main advantage of ACGIH Threshold
Limit Values (TLVs) is that they are reviewed
neither NIOSH nor OSHA updates its standards with any
regular frequency.
Health Hazards of some Gases, , P.E., CIH, Ph.D., May, 1987
Ammonia Gas Exposure Hazards
Ammonia is very soluble in water and, in water, hydrolyzes to ammonium hydroxide, a strong base.
These properties
insure that ammonia gas is an upper respiratory tract and eye irritant.
It dissolves in the water of mucous membranes
(or tears), hydrolyzes and irritates rapidly mainly because of the high pH that results.
Because of this biological
property of prompt irritation, most people cannot tolerate a concentration of ammonia in air sufficiently high to be
Its warning properties assure a negligible hazard from ammonia inhalation if escape is possible.
formaldehyde and other good upper respiratory tract irritants, people can become &hardened& to the irritation
of ammonia and after several exposures can tolerate much higher concentrations than can an unexposed individual.
some circumstances, a hardened person can accept an exposure that will result in inflammation of the throat, bronchi, and
possibly eyes.
An exposure to 300 to 500 ppm for 30 to 60 minutes would cause such an effect and might be hazardous to
The current TLV for ammonia is 25 ppm with a short-term exposure limit of 35 ppm.
Both were designed to be low enough
to cause no irritation in unhardened people.
The OSHA PEL for ammonia is 50 ppm, as is the NIOSH Recommended
Ammonia Gas
Properties, Exposure Pathology, Symptoms, Treatment, Prognosis
The following information about exposure to ammonia gas hazards is based on information from U.S. Army , Noxious Chemicals:
Physical Properties of ammonia:
Ammonia is a colorless
gas, soluble in water, with a pungent odor. Liquid
ammonia is a vesicant.
Occurrence if Ammonia gas in Military Operations or in Civilian Environments:
has not been used in warfare but may be encountered
in industrial accidents, bombings involving refrigeration
plants, and holds of ships as a product of
decomposing material.
Pathology of Human Exposure to Ammonia or Ammonia Gas
Exposure to high concentrations of
ammonia produces prompt and violent irritation of
the eyes and respiratory tract. There may be spasm
a nd edema of the glottis or necrosis of the laryngeal
mucous membranes. Pulmonary edema may develop
and may be complicated by bronchopneumonia.
Symptoms of Exposure to Ammonia or Ammonia Gas
High concentrations produce
violent, burning pain in the eyes and nose, lacrimation,
sneezing, pain in the chest, cough, spasm of the glottis,
and pulmonary edema. Often there is a temporary
reflex cessation of respiration with spasm of the glottis.
Edema of the glottis at a later period may seriously
interfere with breathing. Concentrations of 0.1 percent
are intolerable to humans.
Treatment for Exposure to Ammonia Gas
Treatment for ammonia gas exposure consists of prompt
removal to pure air and administration of assisted
ventilation. Later measures are directed toward the
treatment of pulmonary edema, bronchitis, and
pneumonia.
Prognosis for Humans Exposed to Ammonia Gas
The mortality for people exposed to ammonia gas is high following
severe exposure. With low concentrations, recovery
is usually rapid although bronchitis may persist.
Arsine Gas Exposure Hazards - Arsenic Hydride
Arsine is arsenic hydride, the combination of arsenic metal and hydrogen gas.
Arsine is a water-soluble gas.
given off whenever freshly-generated hydrogen contacts metallic arsenic especially in an acid environment.
lead-acid storage battery approaches full charge (in formation or boosting or simply charging), some hydrogen evolves.
When arsenic is present in the grids of that battery, some arsine is formed and escapes through the vent caps.
battery is seriously overcharged, much hydrogen (and arsine if a lead-arsenic alloy is used in the plates) may be given
an ignition source can then cause the gases to explode.
The main acute effects of arsine on people are lung irritation and hemolysis (destruction of red blood cells).
effects are usually delayed and do not appear until several hours after the exposure that typically occurs during the
acid washing of a tank that has contained an arsenical slag.
Of the two, hemolysis is usually the more serious and is
first indicated by pink or red urine that becomes darker with successive voidings.
Debris from damaged red cells
&clogs up& the kidneys, leading to extremely severe pain and, eventually, to a stoppage of urine flow.
red cells have been destroyed, severe anemia results so that oxygenation of tissue is impaired.
In addition, there may
be severe lung irritation (impeding proper oxygenation of blood); death may result from asphyxiation a few days after the
These effects of arsine are completely avoided if 8-hr exposures are kept at or below 200 ug/cu. m, (0.05 ppm), the
TLV and PEL.
Whether or not arsine has any chronic effects (such as the causation of cancer) is not known because there
has been no study of people or animals chronically exposed to this material.
There are, therefore, no data available
indicating that arsine is a carcinogen.
Of the three &standards setting& groups, NIOSH is the only one that
recommends extremely strict control (2.0 ug/cu. m as determined by 15-min samples) of arsine exposures.
All of the
information upon which NIOSH based its Recommended Standard was (and is) available to anyone, including ACGIH and OSHA,
of course.
If half of the arsine inhaled is excreted in the urine (as seems to be the case for particulate arsenic
compounds), then, inhalation of 200 ug/cu. m should result in a urinary concentration on the order of 666 ug/L.
these circumstances, then, urinary arsenic concentrations might well be useful as indices of arsine exposure/absorption.
However, there is very little data in the literature concerning urine concentrations resulting from measured arsine
exposures.
for more information about arsenic poisoning symptoms and effects.
Bromine Gas Exposure Hazards
Bromine is the only halogen that is a liquid at room temperature.
Its color is a dark rust red as a liquid and
As opposed to the &upper respiratory tract& irritants and &lower respiratory tract&
irritants, bromine is a &whole respiratory tract& irritant.
That is, its main effects are exerted on the deep
lung and may be delayed for some time after the exposure, but it does have far better warning properties than do the
lower respiratory tract irritants such as nitrogen dioxide, phosgene, and ozone.
Bromine causes eye irritation and
lacrimation (tearing) in concentrations below 1 ppm but above the TLV (and PEL) of 0.1 ppm.
Concentrations irritating to the eyes should not be tolerated for more than 15 minutes.
Prolonged overexposure to
bromine can cause dizziness, headache, and cough followed by abdominal pain and, later, lung edema and pneumonia if the
exposure is severe enough.
None of these signs/symptoms is at all likely, however, if irritation (eye or respiratory
tract) is used as a warning to leave the area of exposure.
Carbon Dioxide Gas Exposure Hazards
Our CO2 articles include:
The highest TLV (and PEL) assigned to any material is assigned to carbon dioxide, namely 5000 ppm (NIOSH has
recommended a Standard of 1.0% or 10 000 ppm for a 10-hr work shift with a ceiling of 3.0% or 30 000 ppm for any 10-min
Furthermore, these concentrations are far more an expression of good practice than a line between
&safe& and &dangerous.&
Actually, the concentration of carbon dioxide must be over about 2% (20 000
ppm) before most people are aware of its presence unless the odor of an associated material (auto exhaust or fermenting
yeast, for instance) is present at lower concentrations.
Above 2%, carbon dioxide may cause a feeling of heaviness in
the chest and/or more frequent and deeper respirations.
If exposure continues at that level for several hours, minimal
&acidosis& (an acid condition of the blood) may occur but more frequently is absent.
As the carbon dioxide
concentration climbs above a few percent, the concentration of oxygen in the air inhaled begins to be affected.
carbon dioxide, for instance, the concentration of oxygen in air has decreased from 20.96 to 19.9%.
OSHA has indicated
that the lowest oxygen concentration for shift-long exposure is 19.5%, corresponding to a carbon dioxide concentration
well above 60 000 ppm (6%).
Carbon dioxide concentration, not oxygen concentration, is limiting in such
circumstances.
Details about Carbon Dioxide Poisoning:See
levels, poisoning symptoms, & testing. Our CO2 articles include:
Carbon Monoxide Gas Exposure Hazards
Our CO articles include:
Carbon monoxide is a colorless, odorless, tasteless gas that, physiologically, is a chemical asphyxiant.
inhaled, it combines with hemoglobin more readily than does oxygen, displacing oxygen from hemoglobin and thereby
interfering with oxygen transport by the blood.
A person suffering from carbon monoxide (CO) intoxication may first
experience euphoria (similar to the effect of a martini or two), then headache, followed by nausea and possibly vomiting
as the concentration of carboxyhemoglobin in the blood increases.
To prevent these effects, OSHA has established a PEL
of 50 ppm for an 8-hr exposure, identical to the TLV.
NIOSH, on the other hand, has decided to be more conservative and
recommends a standard of 35 ppm.
All of these concentrations refer to exposures with durations of 8 hr/day, 40 hr/week
for a working lifetime and all are attempts to establish a &no effect& level.
Details about Carbon Monoxide Poisoning:See
hazard levels, poisoning symptoms, & testing
Hydrogen Sulfide Gas Exposure Effects
Hydrogen sulfide
may be found or produced in buildings from a variety of sources and may be noticed as a sulfur, or rotten egg smell or even as a flatulence odor.
Health Effects of Exposure to Hydrogen Sulfide gas
NIOSH Immediately Dangerous To Life or Health Concentration (IDLH): 100 ppm
Potential symptoms: A irritated
eyes, conjunctivitis pain, lacrimation, photophobia, co respirato GI disturbances
Health Effects: Acute systemic toxicity (HE4); CNS effects (HE7) Irritation-Eye, (Conjunctivitis), Lungs---Moderate (HE15)
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. Higher concentrations
(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.
The symptoms depend upon the
concentration of the gas. At the lowest concentrations,
the effects are 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.\
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. - U.S. Army , Noxious Chemicals
Affected organs: Respiratory system, eyes
Details about hydrogen sulfide sources in buildings are in these articles
References for Hydrogen Sulfide gas exposure
&&, United States Department of Labor, OSHA, reference, retrieved 2/2/2014, original source https://www.osha.gov/dts/chemicalsampling/data/CH_246800.html
Methane Gas
(CH4) Exposure Effects
Please see
Nitrogen Oxides Gas Exposure Effects & Hazards
The only oxides of nitrogen of concern in most industrial and commercial enterprises are nitric oxide (NO) and
nitrogen dioxide (NO2).
The main source of both gases is combustion and only under special conditions are appreciable
concentrations of nitric oxide formed.
Nitric oxide oxidizes in air to nitrogen dioxide which is the more toxic of the
two gases.
Nitric oxide, when inhaled, combines with hemoglobin to form nitrosohemoglobin, a carboxyhemoglobin-like material that
rather rapidly is oxidized to methemoglobin.
That is, its main effect is to inhibit transportation of oxygen
by the blood.
Its TLV and PEL are both 25 ppm.
Nitrogen dioxide is a deep lung irritant.
That is, this gas
is not very soluble in water and thus is capable of penetrating deeply into the lung where it undergoes hydrolysis to
other materials (acids) that are the actual irritants.
Because hydrolysis is a necessary condition for irritation and
because hydrolysis takes an appreciable amount of time (several hours in many cases), nitrogen dioxide is known as a
delayed-action lung irritant.
Nitric oxide is colorless and may have little or no odor.
Nitrogen dioxide (and/or its
dimer, nitrogen tetraoxide) is rust red and has a &typical& odor quite notable at 5 ppm and causes eye and
nose irritation at 10 to 20 ppm.
Currently (1987), the TLV is 3.0 ppm with an STEL of 5.0 the PEL is 5.0 ppm.
NIOSH has recommended 1.0 ppm for a Standard.
Oxides of Nitrogen Gas
Properties, Exposure Pathology, Symptoms, Treatment, Prognosis
The following information about exposure to ammonia gas hazards is based on information from U.S. Army , Noxious Chemicals:
Physical Properties of Nitrogen Oxide Gas
The term “oxides of
nitrogen” applies to a mixture consisting of nitric
oxide, nitrogen dioxide, and nitrogen tetroxide. Nitric
oxide is colorless. The other oxides are red-brown
Occurrence
of Nitrogen Oxide Gas in Military Operations or Civilian Exposure
(1) The danger of nitrous fume poisoning is or
cordite) are burned or detonated in poorly ventilation
areas. This may occur in gun pits, armored vehicles,
ship magazines, and turrets. This may also occur in
mining and tunneling operations.
(2) In addition, nitrous fumes are emitted
from fuming nitric acids (white and red) and are
generated by the combustion of certain plastics.
Watch out: improper use of ozone generators to try to kill mold or odors may oxidize certain common plastics found in buildings, leading to the hazards discussed here. [OPINION-DF].
Pathology of Human Exposure to Nitrogen Oxide Gases
Inhalation of nitric oxide causes
the formation of methemoglobin and does not appear
to lead to any tissue lesions. Inhalation of nitrogen
dioxide results in the formation of nitrite that leads to
a fall in blood pressure and to the production of
methemoglobin. Inhalation of high concentrations of
nitrogen dioxide (above 0.5 mg per liter) causes rapid
death without the formation of pulmonary edema.
Somewhat lower concentrations of nitrogen oxide gas exposure result in death with the production of yellow, frothy fluid in the nasal
passages, mouth, and trachea and marked pulmonary
edema. The findings in other tissues are negligible.
Symptoms of Exposure to Nitrogen Oxide Gases
The symptoms following inhalation
of nitrous fumes are due chiefly to nitrogen dioxide.
The symptoms presented depend upon the concentration
of the gas. Exposures to higher concentrations
cause severe local irritation with choking and burning
in the chest, violent coughing, yellow staining of the
mucous membranes, expectoration of yellow-colored
sputum, headache, and vomiting.
Often, these early
symptoms may be mild or entirely absent. After 2 to
24 hours, symptoms start with coughing, nausea,
vomiting, frothy sputum, dyspnea, cyanosis, convulsions,
and signs of lung edema. This train of
symptoms may result in death.
At nitrogen gas exposures to very
high concentrations for short periods of time, the onset
of symptoms is very sudden and marked. Convulsions,
unconsciousness, and respiratory arrest occur
within a short time and death may follow rapidly.
Diagnosis of Nitrogen Oxide Gas Exposure
The diagnosis is made from the
history, symptoms described, and sometimes the pungent
odor of the gas or the yellow discoloration of the
exposed mucous membranes.
Treatment for Exposure to Nitrogen Oxide Gas
Treatment of casualties with symptoms
of pulmonary irritation is the same as for CG
poisoning (chap 5).
Prognosis for People Exposed to Nitrogen Oxide Gases
The few cases with symptoms
referable to the CNS either die quickly or, on removal
to fresh air, recover spontaneously. Fatal cases
usually die within 48 hours. Bronchopneumonia and
varying degrees of pulmonary fibrosis and emphysema
often follow recovery from the acute stage.
NOX Reference: Toxicity of Oxides of Nitrogen
, Vol III of III, US EPA, EPA600/8-91/049cF, August 1993, web search 08/28/2010, original source: http://nepis.epa.gov [Large PDF 25MB]
Key chapters in this document evaluate the latest scientific data on (a) health effects of
NOx measured ill laboratory animals and exposed human populatIOns and (b) effects of NOx
on agricultural crops, forests, and ecosystems, as well as (c) NOx effects on visibility and
nonbiological materials.
Other chapters describe the nature, sources, distribution,
measurement, and concentratiOns of NOx m the environment These chapters were prepared
and peer revived by experts from various state and Federal government offices, academia,
and private industry for use by EPA to support decision makIng regarding potentIal risks to
public health and the enVIronment Although the document IS not intended to be an
exhaustIve literature reVIew, It IS intended to cover all the pertinent literature through early
Ozone Gas Exposure Hazards
Ozone is a kind (called an &allotrope&) of oxygen . It is formed in the ionosphere by the action of
ultraviolet radiation from sunlight on oxygen.
Lightning strokes are another natural source of ozone and the
characteristic odor of that material can often be noted during and after a thunderstorm.
When pollutants are emitted
into the air either by man or nature, almost all are eventually removed by one or more of several processes including
reaction under the influence of ultraviolet radiation.
One series of such reactions results in the formation of ozone as
a &secondary& (formed by reaction in the air) air pollutant, often in rather high concentrations (several
tenths of a part per million).
As ozone can be formed by nature's sparks (lightning), it can also be formed by man's.
Whenever an electrical
spark or corona occurs in air, some ozone is formed.
This accounts for the characteristic odor noted near an operating
electric motor such as an electric shaver.
Because ozone is found in so many places, its toxicity (ability to injure a
living organism by other than mechanical means) has been investigated extensively since the early 1900s.
Experimentation
has shown that the odor of ozone can be detected and identified by most people at a concentration of from 0.02 to 0.05
ppm (parts ozone per million parts air + ozone).
As the concentration increases to a few tenths of a part per million,
the first effect noted is likely to be a feeling of dryness in the back of the throat.
If a concentration on the order
of 0.2 or 0.3 ppm is inhaled more or less continuously for several hours to a few days some lung irritation may
Higher concentrations of ozone can produce several kinds of toxic effects if exposures are sufficiently prolonged.
irritation (despite newspaper and TV accounts seemingly indicating otherwise) occurs only at concentrations high enough
to result in other, more severe, toxic effects.
Ozone is a very reactive substance.
It will readily react with just
about any material capable of being oxidized, and with many that are not.
The material with which it reacts may be a gas
or vapor, a particle floating in the air (a mold spore, for example), or a solid (or liquid) surface.
For this reason,
when ozone is present in most enclosed spaces its concentration declines quite rapidly with time.
Of course, if ozone is
being generated more rapidly than it is destroyed by reaction, its concentration can build up.
This is the main reason
why devices that produce relatively large amounts of ozone are safe only in relatively large enclosures and why the ozone
generation rate should be reduced in small enclosures.
Ozone is well known for its ability to eliminate certain odors.
How this is accomplished is controversial.
concentrations just above the odor threshold, some odors do seem to vanish.
The main reason for this may be ozone's
ability to desensitize the olfactory apparatus so that the odors can no longer be perceived.
Some evidence indicates
that this may be the case at least occasionally.
Other evidence indicates that ozone may react with the odor-causing
substances, eliminating them from the air (this is probably the only mechanism that operates when concentrations are
below the odor threshold).
Finally, some people have insisted that even if ozone does not paralyze the olfactory sense, its odor is such that it
&masks& other odors.
Perhaps all three mechanisms operate, each in its own area of effectiveness.
As with all
other materials, ozone has a dose-effect relationship with a threshold.
That is, once the threshold dose has been
exceeded, toxic effects are proportional to dose.
For inhaled gases, dose is proportional to both time and
concentration.
If the duration of exposures cannot be controlled (as is usually the case), then the concentration must
be kept low enough so that no injury will occur even from prolonged and repeated exposures.
For ozone, that
&threshold& concentration is 0.1 ppm.
So long as concentrations are kept at or below that level, injury is not
expected even in the most sensitive workers so long as their exposure durations coincide reasonably well with or are less
than the 8 hr/day, 40 hr/wk regimen.
This &threshold& level is accepted by the American Conference of
Government al Industrial Hygienists (and is called the Threshold Limit Value by that organization) and by the
Occupational Safety and Health Administration, OSHA.
The TLV or OSHA's Permissible Exposure Level (PEL) is not a fine
line between safe and non-safe.
Instead, it represents the best judgment of a group of experts of the highest
concentration that can be inhaled repeatedly by a population of workers with no resulting injury.
Higher concentrations
may or may not have any particular effect on a specific individual.
Ozone is a highly toxic gas but even highly toxic substances can be encountered safely.
The main concern with this
material is that concentrations to which people are exposed do not average more than 0.1 ppm over an 8-hr day, and do
not exceed that value by more than a factor of 2 or 3 during the exposure.
More depth: see
Use of Ozone as a &mold& remedy is ineffective and may be dangerous. Our complete list of articles about ozone can be found at that article.
Propane Gas or LP Gas Exposure Hazards
The greatest LP gas or propane gas exposure risk other than fire or explosion,
would be not the exposure to LP gas or propane gas itself but the prolonged absence of sufficient oxygen if someone is enclosed in a space with high concentration of propane. No
long term exposure health risks associated with LP gas or propane have been
reported at low concentrations.
At air concentrations below
1000 ppm propane is virtually non-toxic. Brief exposures to 10,000 ppm 100,000 ppm can produce slight dizziness after a few minutes of
exposure, but is not noticeably irritating to the nose and throat.
Propane is a simple asphyxiant. High concentrations of
propane can displace oxygen and cause asphyxiation. Oxygen content in the
atmosphere must not be allowed to fall below 18%.
Effects of oxygen deficiency
are: 12-16% breathing and pulse rate increased, muscular co-ordination
10-14% emotional upset, abnormal fatigue, d
6-10%: nausea and vomiting, collapse or l below 6%:
convulsive movements, possible respiratory collapse and death.
The gas does
not affect the skin. Contact with liquified gas escaping from its high
pressure cylinder may cause frostbite. Symptoms of mild frostbite
include numbness, prickling and itching in the affected area. Symptoms
of more severe frostbite include a burning sensation and stiffness of
the affected area. The skin may become waxy white or yellow. Blistering,
tissue death and gangrene may also develop in severe cases.
range contact with liquefied propane gas may cause injury
characteristic of a thermal burn with swelling, fluid accumulation and
extreme redness. Tissue death and gangrene may also develop.
The gas does
not cause eye irritation. Contact with liquified gas escaping from its
high pressure cylinder may cause freezing of the eye. Permanent eye
damage or blindness could result. -
In some areas propane gas and similar fuels may be referred to by the name of their distributor, such as && gas referring to the blue fuel gas cylinders and related products sold in South Africa.
Propylene Gas Exposure Hazards
Propylene is a simple asphyxiant (that is, it acts by dilution of oxygen) and a rather poor anesthetic.
high concentrations are required to produce any effect at all.
No TLV or PEL has ever been established for this material
and NIOSH has not recommended a Standard.
Its lower explosive limit is 2% in air (the upper is 11.1%) and a reasonable
value for a maximum permissible concentration (suggested by Gerarde in Patty's Industrial Hygiene and Toxicology, vol
2, p. 1204, Interscience, New York, 1963) is 1/5 of the LEL or 4000 ppm.
Sulfur Dioxide Gas Exposure Hazards & Effects
For sulfur dioxide, the TLV had been 5.0 ppm for many years, but in 1978 ACGIH announced its intention to reduce
that TLV to 2.0 that was done in 1980.
The reason for this was recent information indicating that chronic (long
term, repeated) exposure to sulfur dioxide concentrations near 5.0 ppm was found to have some minimal effects on working
populations.
Sulfur dioxide is an upper respiratory tract irritant and acute (single or short-term) exposures cause
nothing but irritation of the nose and throat.
Long term exposures to sulfur dioxide concentrations in excess of 2.0 ppm
can be expected in some cases to cause minor lung changes.
Potential Symptoms of sulfur dioxide gas exposure: Eye, nose,
rhinorrhea, choking, coughing, shortness of breath, chest
pain, pulmonary edema, reflex eye,
frostbite (on contact with liquid); chronic bronchitis.
Affected organs: eyes, skin, respiratory system.
Health Effects of sulfur dioxide gas exposure: Irritation-Eye, Nose, Throat,
Skin---Marked (HE14) Mutagen (HE2); Respiratory effects---
Bronchoconstriction, pulmonary edema, reactive airways dysfunction
syndrome (HE9 and HE11); Suspect reproductive effects (HE5)
Affected Organs: Eyes, skin, respiratory system
OSHA Note:
Sulfur dioxide is listed by the FDA as generally recognized as safe when
used in accordance with good manufacturing practice as a preservative
of fruits or vegetables (21 CFR 182.3862). [12]
Sulfur Oxides Toxicity and Exposure Limits References:
Sulphur dioxide Sulfur dioxide SO2 exposure limits (PELS typically are at 5 ppm or less by some standards) are at
in our article titled:
Watch out: NIOSH Immediately Dangerous To Life or Health Concentration (IDLH): 100 ppm
Sulfur dioxide & other Oxides: , Vol. III, US EPA, Environmental Criteria and Assessment Office, Research Triangle Park NC 27711, Dec. 1982, EPA-600/8/2-029c. Web search 08/26/2010, original source: http://nepis.epa.gov [large PDF]
OSHA citations for sulphur dioxide hazards & effects:[12]
NIOSH Pocket Guide to Chemical Hazards: .
International Chemical Safety Cards (WHO/IPCS/ILO): .
Koksal, N., Hasanoglu, H.C., Gokirmak, M., Yildirim, Z. and Gultek,
A.: Apricot sulfurization: an occupation that induces an asthma-like
syndrome in agricultural environments.
Am. J. Ind. Med. 43(4): 447-453, 2003.
Piiril?, P.L., Nordman, H., Korhonen, O.S. and Winblad, I.: A
thirteen-year follow-up of respiratory effects of acute exposure to
sulfur dioxide.
Scand. J. Work Environ. Health 22(3): 191-196, 1996.
Pohanish, R.P. (editor): Sulfur Dioxide.
In, Sittig's Handbook of Toxic and Hazardous Chemicals and Carcinogens, Fourth Ed., Vol. 2.
Norwich, NY: Noyes Publications, William Andrew Publishing, 2002, pp. .
we discuss several chemicals and gases found indoors and offer advice for reducing indoor exposure.
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Frequently Asked Questions (FAQs)
Question: Sulphur dioxide SO2 exposure limits?
[This question originally appeared in reader comments at ] - Ed.]
This article is interesting. I think I understand the concept but I have an application that use an analyzer.
To calibrate this instrument, I need to use an 8% SO2 compress gas
cylinder (cylinder capacity 5m3). This is located in a sealed 10x10x10
room, so my room is 1000m3 and unventilated.
Worst case scenario, the cylinder empties in this room. Is this an
accute risk knowing that 3000 ppm is the LC50 (1/2hour) limit and the
bottle contains 80000ppm? I have a bit of difficulties to put some math
around this. Could you please explain?
I think 8% concentration x 5m3 cylinder = 0.4m3 of SO2 release in the room.
The gas will occupy 0.4m3/1000m3 = 0.04% of the room volume which is 400ppm.
400ppm & LC50 3000ppm = Low Risk?
Syl, your question was a bit unclear and makes me worry that you are messing with gases without proper education or preparation. You are asking about Sulphur dioxide (SO2) in an article about Carbon dioxide (CO2) - in any event, if you are asking about recommended exposure limits for Sulphur dioxide SO2,
Sulphur dioxide exposure limits: OSHA PELs for SO2 and other recommended exposure limits are given at
in our article titled: . Depending on the standard, SO2
PELs range among 0.25 ppm, 2 ppm, or 5 ppm. - all significantly less than your 400 ppm.
Watch out: NIOSH Immediately Dangerous To Life or Health Concentration (IDLH): 100 ppm
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&&, United States Department of Labor, OSHA, reference, retrieved 2/2/2014, original source https://www.osha.gov/dts/chemicalsampling/data/CH_246800.html
discusses Ammonia, Carbon Monoxide, Hydrogen Sulfide, Oxides of Nitrogen, Hazards caused by fire,
Mark Cramer, Tampa Florida, Mr. Cramer is a past president of ASHI, the American Society of Home Inspectors and is a Florida home inspector and home inspection educator. Mr. Cramer serves on
the ASHI Home Inspection Standards. Contact Mark Cramer at: 727-595-4211
an ASHI member and a home inspector (The House Whisperer) is located in Glen Allen, VA
23060. He is also a contributor
in several technical areas such as plumbing and appliances (dryer vents). Contact Mr. Cranor at 804-747-7747 or by Email:
120 Carlton Street Suite 407, Toronto ON M5A
4K2. (416) 964--268-7070 . The firm provides professional
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[1] CADAC, Commercial And Domestic Appliance Company,
produces a range of gas and camping products. we are guessing that typically
they'd be marketing LP - liquid propane. Web search 07/22/2010 - original source: http://www.cadac.co.za/index.php?page=compan describes Cadac products. their tel: support line on
[2] Canadian Centre for Occupational Health and Safety, web search 07/22/2010, original source: http://www.ccohs.ca/oshanswers/chemicals/chem_profiles/propane/health_pro.html
[3] &Residential Electric Water Heater Installation Instructions and Use & Care Guide&, American Water Heater Co., October 2001, American Water Heater Co., Johnson City, TN, [manufacturer of residential & commercial water heaters, also manufacturer of Polaris/Commercial water heaters], Tel: 800-999-9515, web search 1/12/2012, original source: /support/manuals/res-elect.pdf [copy on file]
[4] Portions of this
data were extract5ed from CompuServe's SAFETYNET forum 1989 and from the
following articles:
[5] [] GASES.TOX 08-May-87 17240 53 Title: Toxicity & hazards discussion of various gases
[6] Keywords: Discussion of the toxicity and hazards of various gases, ammonia,
arsine, bromine, carbon dioxide, carbon monoxide, ozone, nitric oxide, nitrogen
dioxide, propylene, and sulfur dioxide.
[7] [74756,40] CO 20-Dec-86 7050 40 Title: Carbon Monoxide discussion by Jack Peterson
This is a discussion of carbon monoxide from lift trucks, by Jack Peterson,
in response to a query on the message board. Excellent information from one of the leading experts on the
topic. ASCII file - Uploaded by Len Wilcox, 74756,40 [an old Compuserve address].
[8] [] COALAR.TXT 19-Aug-88 12814 17 Title: Message thread on Carbon Monoxide Alarms
[9] Keywords: CO CARBON MONOXIDE ALARM ALARMS MONITOR MONITORING TESTING
[10] [Portions of this file was excerpted and edited from contents of a 1986 Compuserve message board discussion on Carbon Monoxide alarms, featuring
comments by one of the leading authorities on CO, Jack Peterson.-- DJF]
discusses Ammonia, Carbon Monoxide, Hydrogen Sulfide, Oxides of Nitrogen, Hazards caused by fire
[12] Sulfur dioxide, Exposure Limits, U.S. Department of Labor, OSHA, web search 4/12/12, original source:
http://www.osha.gov/dts/chemicalsampling/data/CH_268500.html
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 . Also see our
, Carson Dunlop & Associates, Toronto, Ontario, 25th Ed., 2012, is a bound volume of more than 450 illustrated pages that assist home inspectors and home owners in the inspection and detection of problems on buildings. The text is intended as a reference guide to help building owners operate and maintain their home effectively. Field inspection worksheets are included at the back of the volume. Special Offer: For a 10% discount on any number of copies of the Home Reference Book purchased as a single order. Enter INSPECTAHRB in the order payment page "Promo/Redemption" space.
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Building inspection education & report writing systems from
Toronto, have provided us with (and we recommend) Carson
Dunlop Weldon & Associates'
to manufacturer's
model and serial number information for heating and cooling equipment
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CCSP, 2008: . A Report by the U.S.
Climate Change Science Program and the Subcommittee on Global Change Research. [Gamble, J.L. (ed.), K.L. Ebi, F.G. Sussman,
T.J. Wilbanks, (Authors)]. U.S. Environmental Protection Agency, Washington, DC, USA. Web search 08/28/2010, original source: http://nepis.epa.gov/
for Toxic Gas Exposure to Ammonia, Arsine, Arsenic, Bromine, Carbon Dioxide, Carbon Monoxide, Hydride, Ozone - allowable exposure levels and hazard levels
hazard level, poisoning symptoms, & testing
Health Effects of Carbon Dioxide - see &National Advisory Committee for Acute Exposure Guideline Levels (AEGLs)
for Hazardous S Proposed AEGL Values, Federal Register
Document&,
note that these are proposed guidelines
Carbon Dioxide CO2: Geologic Sequestration Health Effects: &Vulnerability Evaluation Framework for Geologic Sequestration of Carbon
Dioxide [on file as /hazmat/CO2_EPA_VEF-Tech_Doc_072408.pdf ] - &, US EPA, EPA430-R-08-009, July 2008, web search August 2010,original source: http://www.epa.gov/climatechange/emissions/downloads/VEF-Technical_Document_072408.pdf
, U.S EPA, web search 08/28/2010, original source:
http://www.epa.gov/climatechange/emissions/co2_gs_tech.html
GTSP, 2006: Carbon Dioxide Capture and Geologic Storage: A Core Element of a A Global
Energy Technology Strategy to Address Climate Change (PDF, 37 pp., 6.05 MB, About PDF).
April 2006, JJ Dooley et al. Global Energy Technology Strategy Program (GSTP)
IPCC, 2005: Special Report on Carbon Dioxide Capture and Storage, Special Report of the
Intergovernmental Panel on Climate Change [Metz, Bert, Davidson, Ogunlade,
de Coninck, Heleen, Loos, Manuela, and Meyer, Leo (Eds.)]. Cambridge University Press, The
Edinburgh Building Shaftesbury Road, Cambridge CB2 2RU England
: a Bibliography with Abstracts, US Environmental Protection Agency, Office of Air Quality Planning and Standards,
Research Triangle Park, North Carolina 27711, December 1976. Web search 08/28/2010, original source: http://nepis.epa.gov.NOTE: because the EPA's original source of this document in PDF format is damaged we have created a text image file, converted to a new PDF for readability.
: US EPA. UFFI (Urea Formaldehyde Foam Insulation) was previously considered a hazard (formaldehyde outgassing). Subsequent research
reg however formaldehyde appears to remain a health concern for sensitive individuals.
: U.S. EPA, web search 08/28/2010, original source:
http://www.epa.gov/climatechange/emissions/co2.html
, Vol III of III, US EPA, EPA600/8-91/049cF, August 1993, web search 08/28/2010, original source: http://nepis.epa.gov [Large PDF 25MB]
Key chapters in this document evaluate the latest scientific data on (a) health effects of NOx measured ill laboratory animals and exposed human populatIOns and (b) effects of NOx on agricultural crops, forests, and ecosystems, as well as (c) NOx effects on visibility and nonbiological materials. Other chapters describe the nature, sources, distribution, measurement, and concentratiOns of NOx m the environment These chapters were prepared and peer revived by experts from various state and Federal government offices, academia, and private industry for use by EPA to support decision makIng regarding potentIal risks to public health and the enVIronment Although the document IS not intended to be an exhaustIve literature reVIew, It IS intended to cover all the pertinent literature through early 1993
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,
detector-tubes and Drager accuro? bellows pump, the Gastec? cylinder pump and detector-tube system produced by Gastec or
we also use Sensidyne's . 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
online document.
& other Oxides: , Vol. III, US EPA, Environmental Criteria and Assessment Office, Research Triangle Park NC 27711, Dec. 1982, EPA-600/8/2-029c. Web search 08/26/2010, original source: http://nepis.epa.gov [large PDF]
U.S. EPA Radon level maps, web search 2005, original source: http://www.epa.gov/iaq/radon/zonemap/zmapp33.htm
&Table Z-1 Limits for Air Contaminants,
Table Z-1& OSHA standard for air contaminant limits (http://www.osha.gov/pls/oshaweb/owadisp.show_document?p_table=STANDARDS&p_id=9992)
- includes for CO2, Carbon dioxide.........| CAS No. 124-38-9 |
ppm | 9000 mg/m3 limits for carbon dioxide as an air contaminant.
Toxic Gas Exposure effects, including links
to toxic gas exposure screening and gas testing protocols.