A Toxic Gas Testing Sampling Plan for Residential Indoor Air Investigations
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- Indoor air quality testing for toxic gases - level of toxicity of gases
- How to test for toxic gases indoors and what levels of each gas are acceptable
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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.
Readers of this document should also see HEAT EXCHANGER LEAKS.
© Copyright 2008 Daniel Friedman, All Rights Reserved. Information Accuracy & Bias Pledge is at below-left. Use the links at page left to navigate this document or to go to Other Website Topics. Green links at left show where you are in our document & website.
I.a. Indoor Residential Toxic Gas Test Selection - Some Suggested Tests
Depending on the building history and occupant complaints, and with advice from industry experts, for screening purposes I select one or more gas detection tubes
prepared by Sensidyne � or Drager � or one or more multiple simultaneous gas detection sets which have been prepared
by Draeger Safety specifically for fire scenes.
Detector tubes, used with a special calibrated Sensidyne or Drager pump
provide specific, accurate tests for the presence of target substances at the
moment of testing. A list of gas tests and test sets which I have frequently used in field investigations is listed below. Other tests for specific
substances: over 200 tests for over 500 different gases are available by using specific detector tubes. I can provide these when there is risk of a specific
substance in a building. Unless there is a reason given for a narrow specific gas test in a building such tests are not economical and are simply "shooting in the dark."
I also select among several methods for particle collection from appropriate
complaint and non-complaint areas, including air sampling, surface tape lifts, surface, carpet, or furniture vacuum. Where bacteriological risks are
considered, such as where there has been a history of sewage leaks, I may include floor surface sterile swabs from the complaint area and control
non-complaint areas. Sample specifics and test results along with related remediation advice are detailed in my Field Investigation and Lab Test Report.
Odor Source Identification & Evaluation
Odor source detection procedures are also available at this website but they are not discussed
in this article. Odor detection and removal are described in detail in our separate odor diagnosis document at
How to Find & Remove Odors, Gases & smells in Buildings
I.b. Indoor Air Investigation Tests for substances in gas form
Draeger
Simultaneous Test Sets I, II, and III:
Building contents and the presence of hazardous substances are unknown at the start of fighting a fire. Studies have shown more than 450 substances are
produced by a fire and possibly in other circumstances. (Not all of them are present at every fire, but 11 inorganic gases are preset at most fires. Ten of
these are addressed by the Draeger Simultaneous Test Sets I and II.
) Set III screens for organic gases. The Draeger Simultaneous Test Sets screen for these specific substances in the
immediate vicinity. These sets also record a broader spectrum of substances, and the reaction systems used are deliberately non-specific in order to screen
for likely and most-dangerous substances. The individual sampling tubes are marked to indicate the presence of the test substances at 1x and 5x the
threshold limit value (TLV) [for maximum short term exposure in industry; there is not a similar residential standard].
a. Drager Simultaneous Test Set I
i. Acid gases
ii. Hydrocyanic acid
iii. Carbon monoxide
iv. Alkaline gases
v. Nitrous fumes
b. Drager Simultaneous Test Set II
i. Sulphur dioxide
ii. Chlorine
iii. Hydrogen sulphide
iv. Carbon dioxide
v. Phosgene
c. Drager Simultaneous Test Set III
i. Keytones
ii. Aromatic hydrocarbons. Calibrated for toluene; benzene and xylene are indicated
with similar sensitivity. The TLV4 for benzene is much lower than xylene
but the acute risk involved in the two substances is alike. They share the same
IDLH (2000 ppm).
iii. Alcohols. Such as methanol.
iv. Aliphatic hydrocarbons. E.g. n-hexane (extremely low TLV(TWA)=50ppm); the TLV
for most of the other aliphates is assessed to 300 ppm. The acute risk involved in hexane, heptane, and octane is almost identical; all substances are assessed to similar IDLH values.
v. Chlorinated hydrocarbons. Imprinted tube values pertain to perchloroethylene. A
general prediction can be made with respect to the sensitivity of other compounds with certain reservations. (Gasoline vapors will shorten the reading as long as their concentration is more than 100 ppm).
Benzene Gas Characteristics, Toxicity, Simple Gas Exposure Measurements
Benzene
0.5/a tests in the indoor environment
If there is a particular concern for Benzene I perform a test for this substance. I select a sampling tube which is not Benzene specific in order to
also screen for other aromatic hydrocarbons including toluene, xylene (more likely to be in carpet out gassing than benzene) and ethel benzene. Sensitivity
0.4 to 10 ppm (40 to 2 strokes). +/30%.
More information about gas hazards, gas toxicity, or other environmental hazards is available from public and professional agencies and associations
such as the American Industrial Hygiene Association (AIHA) www.aiha.org, OSHA www.osha.gov, and the Mine Safety & Health Administration www.msha.gov.
Also see Industrial Hygiene News.
Carbon Dioxide Gas Toxicity, Simple Gas Exposure Measurements
Carbon dioxide
100/a
I have this test available for field use as a general indicator of the level of fresh air and air exchange in a building, but not if the building is
unoccupied or aggressively ventilated at the time of my inspection. If used, I perform this test using the Gastec pump and tubes produced by Sensidyne. I do
not perform this test separately if I am using the Draeger Simultaneous Test
set as it is already included in that set. Sensitivity 100 " 3000 ppm. 0.01 " 0.3 Vol.-%.
Details about carbon dioxide gas toxicity or CO2 exposure hazards are provided in a separate article at
Toxicity of Carbon Dioxide Gas Exposure, CO2 Poisoning Symptoms, Carbon Dioxide Exposure Limits, and Links to Toxic Gas Testing Procedures
Carbon Monoxide Gas Toxicity, Simple Gas Exposure Measurements
Carbon monoxide
2/a:
I may use this test as a safety screen in buildings where there is other evidence of a questionable gas-fired heater. If used, I perform this test using
the Gastec pump and tubes produced by Sensidyne. I do not perform this test separately if I am using the Draeger Simultaneous Test set as it is already
included in that set. Sensitivity 2-60 ppm. Alternate: Sensidyne� Gastec� 1/La 8-1000 ppm or 25-500 ppm.
Readers should also review our more detailed review of CO hazards at Toxicity of Carbon Monoxide Gas Exposure, Carbon Monoxide CO Poisoning Symptoms, Carbon Monoxide Exposure Limits, and Links to Toxic Gas Testing Procedures
More information about gas hazards, gas toxicity, or other environmental hazards is available from public and professional agencies and associations
such as the American Industrial Hygiene Association (AIHA) www.aiha.org, OSHA www.osha.gov, and the Mine Safety & Health Administration www.msha.gov.
Also see Industrial Hygiene News.
Formaldehyde Gas Characteristics, Toxicity, Simple Gas Exposure Measurements
Formaldehyde 0.2/a:
because this gas is produced at virtually all house fires and because it is a well-known respiratory and eye irritant produced by many building materials even without combustion effects, if there are owner/occupant complaints, this test may be performed using the Gastec pump and tubes produced by Sensidyne or
by the Draeger accuro pump and their tubes. Sensitivity 0.2 to 2.5 / 0.5 to 5 ppm at 10 / 20 strokes. Alternative: Sensidyne � Gastec� 91/L 0.1-40.0 ppm
Formic acid Gas Characteristics, Toxicity, Simple Gas Exposure Measurements
Formic acid 1/a:
because this gas screen addresses acid gases which can be expected to be produced by fire, heat, or oxidation (such as from ozone treatment) in commercial and residential properties it is an important screen for this topic. Sensitivity 1 to 15 ppm, 20 strokes.
More information about gas hazards, gas toxicity, or other environmental hazards is available from public and professional agencies and associations
such as the American Industrial Hygiene Association (AIHA) www.aiha.org, OSHA www.osha.gov, and the Mine Safety & Health Administration www.msha.gov.
Also see Industrial Hygiene News.
Ozone Gas Characteristics, Toxicity, Simple Gas Exposure Measurements
Ozone :
at high or low levels (various test sensitivities are available) produced by popular indoor air "purifiers" and by commercial treatments for odors is a
highly-reactive oxidizing gas which is dangerous to lung tissue itself. This gas may react with other building materials (as an oxidant) to produce
secondary outgassing products which are also irritants or potentially unsafe. Ozone is highly reactive and volatile and may not be present in a building long
after it was applied. Choice of use or omit this screen depends on the circumstances of the particular investigation. As a regular practice I include
this screen where ozone generating equipment is in use or where commercial equipment has been very recently in use. Sensidyne� #182SB 2.5-100 ppm / #182U
0.025 " 3.0 ppm.� See Ozone Warnings
at http://www.inspect-ny.com/sickhouse/OzoneWarnings.htm
Details about Ozone Gas hazards and the use of ozone generators or using ozone as a mold remedy are provided in depth at the following articles:
Toluene Gas Characteristics, Toxicity, Simple Gas Exposure Measurements
Toluene 5/b:
because this is one of the most sensitive gas screens available to address gases which can be expected to be produced by fire, heat, or oxidation (such as
from ozone treatment) in commercial and residential properties it is an important screen for this application. Toluol is a common contaminant produced by
oxidized or burning carpets. Sensitivity 5-300 ppm.
II.c. Associated Particulate Testing
These tests are not normally part of indoor gas testing but may be added on request or based on site conditions.
Non-regulated particulates,
such as soot from fires, can include ultra-fine particles which can be breathed deeply into the gas-exchange area of the lung. I use both settled surface dust collection (adhesive tape) and surface or crevice-dust collection (particle collection by vacuum using
Zefon-type "Air-o-cel(R)" or MCE-filter cassettes) to obtain material for microscopic examination. Quantitative testing using other methods that permit calculating of particle exposure by weight are available but I do not employ them [it is outside my area of expertise]. If such particles were collected and examined
they are shown in the Lab Report.
Tests for Common indoor allergens & particles such as mold, pollen, cat or dog dander, fiberglass insulation fragments
such as animal dander, insect fragments, mite fecals, pollen, and mold spores may be sampled by a variety of means: slit-impaction air samplers, vacuum samples, surface tape, bulk, swab, and culture. The specifics of what methods were used are in the Lab Report
Indoor Gas Testing Limitations, Exclusions,
Standards, and Definitions
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General Information about Exposure, Standards, Definitions
Gas Exposure Standards (workplace-based)
The purpose of my inspection and testing is to perform a general screen for the presence of specific problematic substances in response to specific
concerns raised regarding the target property. Individual complaints about indoor air quality can occur at extremely-low levels of certain gases or
particles, in fact at levels considerably below typical allowable industrial permitted exposure levels (PEL's). Therefore I may select tests which screen
for levels of gases considerably below permitted limits for industrial workplace exposure.
Gas Tests: My test equipment is checked for proper operation and calibration before and after the investigation; gas detection tests are
conducted under operating conditions meeting the manufacturer's requirements; these tests are applicable only to the place, time, and date of measurement;
the tests are not technically exhaustive. Several instruments are used, depending on whether we are screening for presence/absence of combustible
gases, checking general indoor air quality, or testing and making quantitative measurements of specific gases in an environment. Some instruments are particularly helpful in tracking odors or leaks to their source.
Draeger Sampling Pump: I use the Draeger accuro � Pump and Draeger-Tubes for gaseous substance sampling for both detecting the presence/absence of specific gases and for quantitative measurements of gas levels.
The Sensidyne Gastec piston pump and Gastec� tubes for test for presence/absence of and level of certain gaseous substances.
Both of these toxic gas testing pumps are factory calibrated at 100 cc, and are leak-tested before and after each investigation. The adsorption tubes used
for substance screening/identification are factory-calibrated. Other tests for specific substances: over 200 tests for over 500 different gases are available
by using specific detector tubes. I can provide these when there is risk of a specific substance in a building. Unless there is a reason given for a narrow
specific gas test in a building such tests are not economical and are simply "shooting in the dark."
The TIF 8850 combustible gas detector is a broad-spectrum gas screening instrument which is also useful to track and pinpoint the source of odors or leaks. A partial list of gases detected by the TIF 8850 and its detection limits includes: Acetone 50ppm, Acetylene 50ppm,
Alcohols, Ammonia (R717) 20ppm, Benzene, Iso-Butane (R600a) 500ppm, Chlorine 1ppm, Ethane (R170) 500ppm, Ethylene 500ppm, Gasoline 1ppm, Hydrogen 500ppm,
Hydrogen Sulfide 5ppm, Lacquer Thinners, Methane (Natural Gas) 500ppm, Methyl Chloride 5ppm, Methanol 50ppm, Methyl Ether 500ppm, N-Butane, Naphtha, Propane
("bottled gas" R290) 500ppm, Toluene, Vinyl chloride 5ppm. MDL are generally 1-500 ppm. The device uses a TIF 8801 sensing tip.
General exposure limits reference list for specific gases tested indoors
My general notes for specific gases follows. See the NIOSH Pocket Guide to Chemical Hazards (this document is available online). Other comments in this section are from "Health Hazards of some Gases" Jack E. Peterson, P.E., CIH, Ph.D., May, 1987.
Ammonia Gas Characteristics, Toxicity, Simple Gas Exposure Measurements
Ammonia
:
"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 Standard."
Arsine Gas Characteristics, Toxicity, Simple Gas Exposure Measurements
Arsine :
"The 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." (Op. cit.)
Benzene Gas Characteristics, Toxicity, Simple Gas Exposure Measurements
Benzene
0.5/a: for this test I select a sampling tube which is not Benzene specific (Draeger Benzene 0.5/a) in order to also screen for other aromatic hydrocarbons including toluene, xylene (more likely to be in carpet out gassing than benzene) and ethel benzene.
Bromine Gas Characteristics, Toxicity, Simple Gas Exposure Measurements
Bromine :
"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." (Op. cit.)
Carbon Monoxide Gas Characteristics, Toxicity, Simple Gas Exposure Measurements
Carbon monoxide
:
in general, no carbon monoxide (CO) should be found indoors in living or working spaces when performing an instantaneous check. But CO monitors may be
expected to sound an alarm when a time-weighted exposure level reaches 500 ppm, as that threshold is intended to protect lives while avoiding sounding false
alarms that may occur, for example, when there is a brief, low-level CO release when a gas-fired appliance is first ignited. NIOSH recommends a conservative
PEL of 35 ppm, referring to an exposure of 8 hours/day, 40 hours/week, for a working lifetime " a workplace exposure limit.
Readers should also review our more detailed review of CO hazards at Toxicity of Carbon Monoxide Gas Exposure, Carbon Monoxide CO Poisoning Symptoms, Carbon Monoxide Exposure Limits, and Links to Toxic Gas Testing Procedures
Carbon Dioxide Gas Characteristics, Toxicity, Simple Gas Exposure Measurements
Carbon Dioxide
"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 period). 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." (Op. cit.)
Details about carbon dioxide gas toxicity or CO2 exposure hazards are provided in a separate article at
Toxicity of Carbon Dioxide Gas Exposure, CO2 Poisoning Symptoms, Carbon Dioxide Exposure Limits, and Links to Toxic Gas Testing Procedures
More information about gas hazards, gas toxicity, or other environmental hazards is available from public and professional agencies and associations
such as the American Industrial Hygiene Association (AIHA) www.aiha.org, OSHA www.osha.gov, and the Mine Safety & Health Administration www.msha.gov.
Also see Industrial Hygiene News.
Formaldehyde Gas Characteristics, Toxicity, Simple Gas Exposure Measurements
Formaldehyde
As an additional example using Formaldehyde, in a screen I may test for very low levels in a building (.05 ppm), but the range of human response (also widely variable individually) may be summed as follows:
> 3.0 ppm = respiratory impairment and damage
> 1.0 ppm = possible nasopharyngeal cancer
> 0.5 ppm = irritation to eyes & mucous membranes
> .01 ppm = mild irritation or allergic sensitization in some people
Formic Acid Gas Characteristics, Toxicity, Simple Gas Exposure Measurements
Formic acid
this gas screen addresses acid gases which can be expected to be produced by fire, heat, or oxidation (such as from ozone treatment) in commercial and
residential properties. Formic acid is readily metabolized and eliminated by the body. Nonetheless, some chronic
effects have been documented. Excessive inhalation is a respiratory tract irritant. Repeated exposure (at higher levels) can result in an allergic reaction. It is a suspected mutagen, may cause
long-term liver and kidney damage. More about formic acid and its exposure effects can be read at
http://encyclopedia.lockergnome.com/s/b/Formic_acid
and at Cornell University's MSDS files:
http://msds.ehs.cornell.edu/msds/siri/files/ckb/ckbjy.html
Methane Gas Hazards, Methane Gas Toxicity vs. Methane Explosion & Asphyxiation Risks, How to Measure Methane Gas Levels
Methane Gas Hazards are primarily of explosion or asphyxiation
We commented at Septic System Safety that methane gas which maybe encountered in septic system is both explosive
and an asphyxiant. A thoughtful reader, George Fielder, previously a salesperson for GfG Instrumentation, pointed out that these are the hazards. (We had inaccurately stated that methane gas was "toxic".)
Measurement Instruments for Levels of Methane Gas
Mr. Fielder added that additionally, toxic and combustible gases like methane and H2S that would be found in a septic tank can be readily measured by a portable,
handheld gas monitor that can be rented from almost any safety equipment supply company or trench equipment rental company like United Rentals.
They are easy to use and understand direct reading instruments that if nothing else might satisfy the curiosity of the do-it-yourselfer who likes
to stick his nose in it. True the user will need to know and understand the measurement scale and exposure levels for the particular gases being
measured but this also can be easily explained when renting said instrument and reviewing an MSDS sheet. Most portable handheld monitors on the market today are less complex than a volt-ohm meter and can readily be understood with a brief explanation.
Consult Your Local Safety Equipment Distributor
Readers who have the need to measure methane gas levels or who have questions about the hazards of entering confined spaces such as septic tanks should
contact their local safety equipment distriutor for further advice. In addition, local fire & emergency service officials as well as gas distribution companies as well as some home inspectors
or environmental testing firms may have expertise and gas testing or measurement equipment on hand.
Readers who own, service, or live on a property which includes a private septic system should review
SEPTIC METHANE GAS hazards and warnings, and should
also review the extensive safety article at SEPTIC & CESSPOOL SAFETY.
More information about methane and other gas hazards, toxicity, or other environmental hazards is available from public and professional agencies and associations
such as the American Industrial Hygiene Association (AIHA) www.aiha.org, OSHA www.osha.gov, and the Mine Safety & Health Administration www.msha.gov.
Also see Industrial Hygiene News.
Stay out of Septic Tanks
However, we emphasize that in ordinary procedures used in the care, repair, or maintenance of septic systems, the safety warnings we've listed above
should be followed with care, and in general, quantitative measurements of the level of methane or other gases are not needed during
a septic system repair.
Nitric Oxide Gas Characteristics, Toxicity, Simple Gas Exposure Measurements
"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 noticeable 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 ppm; the PEL is 5.0 ppm. NIOSH has recommended 1.0 ppm for a Standard." (Op. cit.)
Ozone Gas Characteristics, Toxicity, Simple Gas Exposure Measurements
Ozone
"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." (Op. cit.)
Details about Ozone Gas hazards and the use of ozone generators or using ozone as a mold remedy are provided in depth at the following articles:
More information about gas hazards, gas toxicity, or other environmental hazards is available from public and professional agencies and associations
such as the American Industrial Hygiene Association (AIHA) www.aiha.org, OSHA www.osha.gov, and the Mine Safety & Health Administration www.msha.gov.
Also see Industrial Hygiene News.
Perchloroethylene (tetrachloroethylene) Gas Characteristics, Toxicity, Simple Gas Exposure Measurements
Perchloroethylene (tetrachloroethylene): - drycleaning solvent: [OSHA comments from the January 19, 1989 Final Rule on Air Contaminants
Project extracted from 54FR2332 et. seq. This rule was remanded by the U.S. Circuit Court of Appeals and the limits are not currently in force.]
OSHA's former permissible exposure limits for perchloroethylene (tetrachloroethylene) were 100 ppm as an 8-hour TWA, 200 ppm as a STEL not to be exceeded for more than five minutes in any three-hour period, and 300 ppm as a ceiling. On the basis of the chemical's narcotic effects in humans, the Agency proposed a revised PEL of 50 ppm TWA and a 15-minute STEL of 200 ppm for perchloroethylene; these are the limits recommended by the ACGIH (ACGIH 1986/Ex. 1-3, p. 464). NIOSH (Ex. 8-47, Table N6B) did not concur with the proposed limits and recommended that exposures be maintained at the lowest feasible limit and that this chemical be classified as a potential occupational carcinogen. OSHA has evaluated the health evidence for this substance and has determined that a further reduction in the PEL to 25 ppm as a TWA is warranted, and the Agency is establishing this limit in the final rule. Perchloroethylene is a clear, colorless, nonflammable liquid with an etheral odor.
Perchloroethylene is widely used as a solvent in the dry cleaning industry and in industrial degreasing operations.
The narcotic effects associated with exposure to high levels of this chemical are well documented. A worker exposed to
an estimated concentration of 1470 ppm perchloroethylene and Stoddard solvent for 3.5 hours lost consciousness (Stewart,
Erley, Schaffer, and Gay 1961/Ex. 1-807). The most comprehensive studies of the effects of prolonged exposure to perchloroethylene
vapors on human volunteers were conducted by Stewart and colleagues (Stewart, Hake, LeBrun et al. 1974/Ex. 1-970; Stewart,
Hake, Wu et al. 1977/Ex. 1-971); these investigators concluded that prolonged exposure to 200 ppm results in early signs of CNS depression,
while no response was elicited in men or women exposed repeatedly to 100 ppm for seven hours/day, except that performance on the
Flanagan coordination test was significantly decreased in some exposed subjects (Stewart, Hake, Wu et al. 1977/Ex. 1-971, p. 28).
-- Excerpt from PERCHLOROETHYLENE (TETRACHLOROETHYLENE) - OSHA -- DJ Friedman.
Also see TETRACHLOROETHYLENE TRICHLOROETHYLENE - OSHA.
Also see Tetrachloroethylene (Perchloroethylene) - U.S. EPA
Propylene Gas Characteristics, Toxicity, Simple Gas Exposure Measurements
Propylene
"Propylene is a simple asphyxiant (that is, it acts by dilution of oxygen) and a rather poor anesthetic. Extremely 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. (Op. cit.)
Sulfur Dioxide Gas Characteristics, Toxicity, Simple Gas Exposure Measurements
Sulfur Dioxide
"For sulfur dioxide, the TLV had been 5.0 ppm for many, many years, but in 1978 ACGIH announced its intention to reduce that TLV to 2.0
ppm; 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." (Op. cit.)
Toluene [27]
5/b: gases which can be expected to be produced by fire, heat, or oxidation in commercial and residential properties. Toluol is a common contaminant produced by oxidized or burning carpets.
Trichloroethylene Gas Characteristics, Toxicity, Simple Gas Exposure Measurements
Trichloroethylene:
NIOSH REL: 2 ppm 60�minute CEILING during usage as an anesthetic agent and 25 ppm TWA during all other exposures;
NIOSH considers trichloroethylene to be a potential occupational carcinogen as defined by the OSHA carcinogen policy [29 CFR 1990].
Current OSHA PEL: 100 ppm TWA, 200 ppm CEILING,
300 ppm 5�minute MAXIMUM PEAK IN ANY 2 HOURS.
<.P>
"Trichloroethylene is believed to have been discovered in 1864 and was first commercially produced in Germany in the early 1900s. It has been commonly used for cleaning of metals and other parts since the introduction of the vapor degreasing process in the early 1930s and continues to be the standard by which other cleaning processes are compared. Today, its primary uses are as an intermediate in the production of hydrofluorocarbon refrigerants and as a cleaning agent.
"The health effects of trichloroethylene have been studied extensively. The most significant findings to come out of the many long-term animal studies of the chemical are that it has caused liver and lung tumors in mice. The significance of these tumors to human health is unclear due to species differences in both trichloroethylene metabolism and reaction to the metabolites. This is supported by epidemiology studies of workers exposed to trichloroethylene that generally indicate no overall increase in cancer risk. Although recent studies of a small population of exposed workers in Germany appear to show an increase in kidney cancer, these studies suffer from major design flaws and are inconsistent with the results of larger, better conducted studies.
The International Agency for Research on Cancer (IARC) currently considers trichloroethylene to be "probably carcinogenic to humans" (Group 2A), based on its conclusions that there is "limited" evidence of carcinogenicity in humans. The epidemiological data base for trichloroethylene is considered by the American Conference of Governmental Industrial Hygienists (ACGIH), however, to support classification in Group A5 (Not Suspected as a Human Carcinogen) "since the substance has been demonstrated by well controlled epidemiological studies not to be associated with any increased risk of cancer in exposed humans." The U.S. Environmental Protection Agency currently is conducting a reassessment of the carcinogenic potential of trichloroethylene.
-- quoted from White Paper on Trichloroethylene
See Trichloroethylene - IDLH Documentation U.S. CDC NIOSH
See OSHA comments from the January 19, 1989 Final Rule on Air Contaminants Project
extracted from 54FR2332 et. seq. This rule was remanded by the U.S. Circuit Court of Appeals and the limits are not currently in force.
See OSHA's website of PELs - Permissible Exposure Limits
Vinyl Chloride Gas Characteristics, Toxicity, Simple Gas Exposure Measurements
Vinyl chloride [28] may be a hazard in some building where vinyl products are present
and exposed to heat, fire, or oxidation. I do not perform tests for this substance as it is beyond my experience.
Xylene Gas Characteristics, Toxicity, Simple Gas Exposure Measurements
Xylene
Here is some of the Xylene information on sources, environmental persistence, and toxicity from http://www.scorecard.org/chemical-profiles/html/xylenes.html .
Quoted material from the above web page is italicized below. I've edited for brevity and inserted a few comments. See the web link if you want to see all of the data in that report.
The US EPA site info on this chemical is - http://www.epa.gov/oppt/library/pubs/archive/solvents/finlchr4.htm
Emissions of mixed xylenes have been detected from petroleum refining, motor vehicles, residential wood-burning stoves and fireplaces. Mixed xylenes are used as chemical intermediates, as solvents, in aviation fuel, and in household products such as aerosol paints and lacquers (Howard, 1990).
Xylene is registered as an insecticide. Only one product containing xylene is still registered, although use of this product has been suspended since 1993. It was registered for use on fruit, vegetable and grain crops, on ornamental lawns, gardens and plants. It may be applied to dogs, and animal dwellings as well as around houses and farm buildings (DPR, 1996).
The primary stationary sources [of Xylene] that have reported emissions of m-, o-, and p-xylene in California are manufacturers of motor vehicles and equipment, manufacturers of metal cans and shipping containers, and petroleum refining (ARB, 1997b). [Unless you're near a similar facility, I agree that looking at whatever common environment has been share by the two women you cite - not just in the home]
NATURAL SOURCES of Xylene
m- and p-Xylene occur naturally in petroleum. o-Xylene is found in coal tar, petroleum, forest fires and plant volatiles (Howard, 1990).
INDOOR SOURCES AND CONCENTRATIONS of Xylene
m-, o-, and p-Xylene are widely used as solvents and are present in numerous consumer products. Consumer products with the highest median emissions of xylenes include pens/inks and coatings. Xylenes are also emitted from building materials such as carpet adhesives, vinyl cove adhesive, latex caulk, latex paint, and various moldings. Environmental tobacco smoke is also a common indoor source of xylenes (Hodgson and Wooley, 1991).
ATMOSPHERIC PERSISTENCE of Xylene
The atmospheric lifetime of m-xylene is 14 to 15 hours. The atmospheric lifetime of o-xylene is 25 to 26 hours. The atmospheric lifetime of p-xylene is 24 to 25 hours (Kao, 1994).
HEALTH EFFECTS of XyleneL
Probable routes of human exposure to xylenes are inhalation, ingestion, and dermal contact (U.S. EPA, 1994a).
Non-Cancer: Exposure to xylene vapors may cause eye, nose, throat, and respiratory tract irritation. Xylene is a central nervous system depressant. Acute exposure may cause gastrointestinal effects such as nausea, vomiting, and gastric irritation. By analogy to toluene and benzene, xylene is predicted to cause cardiac arrythmias. Exposure may injure the kidneys.
In mice, rats, and rabbits, inhalation of mixed xylene or one of o-, m-, or p-xylene has resulted in increased post-implantation loss, reduced fetal weight, and other indications of retarded development. Oral exposure at high levels in mice has produced cleft palate and reduced fetal weight (ATSDR, 1993i; IARC, 1989c; HSDB, 1995).
Cancer: No information is available on the carcinogenic effects of mixed xylenes in humans. The U.S. EPA has classified xylene (isomers and mixtures) in Group D: Not classifiable as a carcinogen (U.S. EPA, 1994a). The International Agency for Research on Cancer has classified xylene (isomers and mixtures) in Group 3: Not classifiable as to carcinogenicity (IARC, 1987a).
Volatile Organic Compounds (VOC's) and Mold-related VOC's, MVOC's:
VOC's are an outgas product of many substances such as paints, solvents, and in some cases, organic growths such as mold colonies. There may be aesthetic or health-related
complaints where VOC's or MVOC's are present. The absence of VOC's or MVOC's does not assure that problem molds are absent from a building, as the
production of MVOC's by molds varies by genera/species and specific growth and environmental conditions such as changes in moisture or RH. Unless my report
specifically states otherwise, my inspection and testing excluded these substances.
Notice: I am a consulting professional member of the American Industrial Hygiene Association -
AIHA. I am not a certified industrial hygienist, [29]
and my investigation is not intended to certify any building as meeting any government or industry standards for workplace environments.
FOOTNOTES on Gas Toxicity, Gas Exposure Level Testing, and Gas Exposure Standards
[1] Gas detection tubes are one of the classical measurement techniques of gas
analysis (Ref. Drager Tubes - CMS Handbook). The first detector tube was used in the U.S. in 1919 (for CO). Modern tubes offer quantitative results with a
high degree of accuracy and selectivity. Basically, a "tube" is a glass tube which contains one or more chemical reagents which react with the measured
substance by changing color, hence the name "colorimetric gas detector tubes". In most tubes, the length of stain, combined with the volume of pumped
test-air and with other environmental variables such as RH and temperature provide a quantitative measure of the level of target substance present at the
instant of sample collection. Other methods are available for long-term sampling where that approach is needed.
[2] These tests intended for use during and immediately after fires to protect firefighters and investigators.
[3]Draeger Simultaneous Sets I and II measure inorganic combustion gases. Set
III is for the measurement of organic vapors, most of which are not pertinent to this fire. The specific substances tested and the test results for each are listed in my Lab Report.
[4] Draeger Sampling Pump: I use the Draeger accuro � 100 ml multi-stroke bellows Pump
and Draeger-Tubes for gaseous substance sampling, or the Sensidyne Gastec� 100 ml multi-stroke piston pump and Gastec� tubes for certain gaseous substances. Both pumps are factory calibrated at 100 cc, and are leak-tested before and after each investigation. The adsorption tubes used for substance screening/identification are factory-calibrated.
[5] The 11th substance (phosphine) is related to fertilizer fires and is unlikely at a residential property fire.
[6] IDLH "Immediately Dangerous to Life and Health; TLV" Threshold Limit Value.
[7] Benzene
exposure limits: NIOSH REL: Ca TWA 0.1 ppm ST 1 ppm; OSHA PEL: [1910.1028]
TWA 1 ppm ST 5 ppm
[8] Carbon
dioxide exposure limits: NIOSH REL: TWA 5000 ppm (9000 mg/m3) ST
30,000 ppm (54,000 mg/m3) OSHA PEL: TWA 5000 ppm (9000 mg/m3)
[9] Carbon
monoxide exposure limits: NIOSH REL: TWA 35 ppm (40 mg/m3) C 200
ppm (229 mg/m3); OSHA PEL�: TWA 50 ppm (55 mg/m3)>
[10] Formaldehyde
exposure limits: NIOSH REL: Ca TWA 0.016 ppm C 0.1 ppm [15-minute]; OSHA PEL:
[1910.1048] TWA 0.75 ppm ST 2 ppm
[11] Formic
acid exposure limits: NIOSH REL: TWA 5 ppm (9 mg/m3); OSHA PEL:
TWA 5 ppm (9 mg/m3)
[12] Ozone
exposure limits: NIOSH REL: C 0.1 ppm (0.2 mg/m3); OSHA PEL�:
TWA 0.1 ppm (0.2 mg/m3)
[13] Toluene
exposure limits: NIOSH REL: TWA 100 ppm (375 mg/m3) ST 150 ppm
(560 mg/m3); OSHA PEL�: TWA 200 ppm C 300 ppm 500 ppm (10-minute
maximum peak)
[14] Ammonia
exposure limits: NIOSH REL: TWA 25 ppm (18 mg/m3) ST 35 ppm (27 mg/m3);
OSHA PEL�: TWA 50 ppm (35 mg/m3)
[15] "Health
Hazards of some Gases" Jack E. Peterson, P.E., CIH, Ph.D., May, 1987. This data
is from CompuServe's SAFETYNET forum 1989 and from the following articles:
[73766,1245] GASES.TOX 08-May-87 17240 ; 53
Title: Toxicity &
hazards discussion of various gases
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.
[74756,40]
CO
20-Dec-86
7050
40
Title : Carbon Monoxide
discussion by Jack Peterson
Keywords: CO CARBON MONOXIDE JACK PETERSON
DISCUSSION THREAD
This is a discussion of carbon monoxide
from lift trucks, by Jack Peterson, in response to a query on the message
board. Excellent nformation from one of the leading
experts on the topic.
74756,40. [76701,115]
COALAR.TXT
19-Aug-88
12814
17
Message thread on
Carbon Monoxide Alarms
Keywords: CO CARBON MONOXIDE ALARM
ALARMS MONITOR MONITORING TESTING
This file is a message board discussion
on Carbon Monoxide alarms, featuring comments by one of the leading authorities
on CO, Jack Peterson.
[16] Arsine
exposure limits: NIOSH REL: Ca C 0.002 mg/m3 [15-minute];OSHA
PEL: TWA 0.05 ppm (0.2 mg/m3)
[17] Benzene
exposure limits: NIOSH REL: Ca TWA 0.1 ppm ST 1 ppm; OSHA PEL: [1910.1028]
TWA 1 ppm ST 5 ppm
[18] Bromine
exposure limits: NIOSH REL: TWA 0.1 ppm (0.7 mg/m3) ST 0.3 ppm
(2 mg/m3); OSHA PEL�: TWA 0.1 ppm (0.7 mg/m3)
[19] Carbon
monoxide exposure limits: NIOSH REL: TWA 35 ppm (40 mg/m3) C 200
ppm (229 mg/m3); OSHA PEL�: TWA 50 ppm (55 mg/m3)
[20] Benzene
exposure limits: NIOSH REL: Ca TWA 0.1 ppm ST 1 ppm; OSHA PEL: [1910.1028]
TWA 1 ppm ST 5 ppm
[21] Formaldehyde
exposure limits: NIOSH REL: Ca TWA 0.016 ppm C 0.1 ppm [15-minute]; OSHA
PEL: [1910.1048] TWA 0.75 ppm ST 2 ppm
[22] Formic
acid exposure limits: NIOSH REL: TWA 5 ppm (9 mg/m3); OSHA PEL:
TWA 5 ppm (9 mg/m3)
[23] Nitric
oxide exposure limits: NIOSH REL: TWA 25 ppm (30 mg/m3); OSHA
PEL: TWA 25 ppm (30 mg/m3)
[24] Ozone
exposure limits: NIOSH REL: C 0.1 ppm (0.2 mg/m3); OSHA PEL�:
TWA 0.1 ppm (0.2 mg/m3)
[25] Propylene
exposure limits: ?
[26] Sulfur
dioxide exposure limits: NIOSH REL: TWA 2 ppm (5 mg/m3) ST 5 ppm
(13 mg/m3); OSHA PEL�: TWA 5 ppm (13 mg/m3)
[27] Toluene
exposure limits: NIOSH REL: TWA 100 ppm (375 mg/m3) ST 150 ppm (560 mg/m3); OSHA PEL�: TWA 200 ppm C 300 ppm 500 ppm (10-minute maximum peak)
[28] Vinyl chloride: NIOSH REL: Ca; OSHA PEL: [1910.1017] TWA 1 ppm C 5 ppm [15-minute]
[29] Daniel Friedman is a consulting professional member of the American Industrial Hygiene Association - AIHA. His credentials and experience can be viewed at www.inspect-ny.com/danbio.htm
More expert information on this topic
More Information on Toxic Gases, Gas Hazards, & Indoor Air Quality
Toxic Gas Exposure Hazards and Test Protocols including links
to our toxic gas exposure screening and gas testing protocols.
Gases: Toxic gases, indoor exposure levels, testing, identification
- A Toxic Gas Testing Plan: A Gas Sampling Plan for Residential and Commercial Buildings lists some of the toxic indoor gases for which we test, depending on the building complaint and building conditions
- Gas Exposure Hazard Levels: for Toxic Gas Exposure to Ammonia, Arsine, Arsenic, Bromine, Carbon Dioxide, Carbon Monoxide, Hydride, Ozone - allowable exposure levels and hazard levels
- Carbon Dioxide Gas Toxicity hazard levels & testing
- Carbon Monoxide Gas Toxicity hazard levels & testing
- Formaldehyde: US EPA. UFFI (Urea Formaldehyde Foam Insulation) was previously considered a hazard (formaldehyde outgassing).
Subsequent research virtually closed concern regarding this material; however formaldehyde appears to remain a health concern for sensitive individuals.
- Ozone Warnings - 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,
Draeger-Safety's detector-tubes and Drager accuro� bellows pump, the Gastec� cylinder pump
and detector-tube system produced by Gastec or Sensidyne, and
we also use Sensidyne's Gilian air pump. 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 Gas Sampling Plan online document.
- Radon Gas U.S. EPA Radon level maps
Sick house Website - Other Indoor Air
Quality Concerns - Gases
 InspectAPedia TM Home & Site Map - Building Inspection, Diagnosis, & Repair, Environmental Inspection & Testing - Research Website
 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
 Home Inspection Construction Consulting Services & advice for home buyers
 Use this simple, economical mold test kit by following
our instructions on how to collect and mail mold samples to our lab
 Environmental
Inspection, Testing, & Diagnosis On-Site IAQ, Gas, Air Testing, Mold Investigation, Sick Building Diagnosis,
Lab Services, & Remediation Plan Preparation - indoor air quality testing, problem source determination, supporting lab work, written remediation plan addressing
removal of environmental and other hazards and prevention of their recurrence.
 Contact Daniel Friedman for website content suggestions or for fee-paid consulting
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