Environmental Engineering Reference
In-Depth Information
Table 9.3
Methods Used to Characterize Contaminants/Contaminant Emissions
Associated with Indoor Sources
Laboratory Studies
Extraction and Direct Analysis
Provides information on material composition
Does not provide information on actual emissions or rates
Static Headspace
Provides qualitative and quantitative emissions data
Does not provide data on emission rates
Static Equilibrium Tests
Provides data on HCHO emission potentials from wood products
Dynamic Chamber Studies
Small Chambers
Provides emission composition/rate data for controlled environmental conditions
Chamber size limits use to small samples
Large Chambers
Provides emission composition/rate data under controlled environmental
conditions; used to evaluate emissions from large products
Used to simulate real-world conditions
Full-Scale Studies
Test Houses
Provides emission composition/rate data under semi-controlled real-world
conditions; useful for validating chamber emission test results using IAQ models
Source:
From Tichenor, B.A., Ed.,
Characterizing Sources of Indoor Air Pollution and Related Sink
Effects,
ASTM STP 1287, American Society of Testing Materials, West Conshohocken, PA, 1996,
10. With permission.
II. Source emissions characterization
A variety of techniques and systems are used to characterize emissions from
indoor sources, emission rates, changes in emissions over time, and potential
A. Laboratory methods
Several techniques are used to determine extractable compounds from
source materials and to infer potential emissions. These may be directed to
a single compound (e.g., HCHO) or multiple compounds (VOCs).
Extraction techniques typically attempt to identify and quantify sub-
stances present which are not intentionally a part of the product material
(e.g., free HCHO associated with urea-formaldehyde resins, free styrene
associated with styrene butadiene latex, etc.). Such free HCHO and styrene
are extracted by solvents such as water, sodium bisulfite, or toluene in the
first case, or an organic solvent in the second case. Extraction by methylene
chloride or other solvents followed by gas chromatography/mass spec-
