Vapour Intrusion Analysis

Vapour Instrusion
Vapour intrusion pathway poses an unacceptable risk to human health and has received increased attention recently. Vapour intrusion is defined as the migration of volatile organic compounds (VOCs) from the subsurface into overlying buildings. VOCs present in contaminated soil or groundwater can emit vapors that may migrate through subsurface soil into buildings through cracks in foundation, basement walls, or pipe lines. Such vapour intrusion can affect the indoor air quality and cause potential chronic health risks due to long term exposure of the chemical vapours.


Vapour intrusion into buildings can occur from contamination of soil and groundwater, which may happen due to leaks from underground storage tanks, pipe lines, contaminated soil gas, or surface spills. For example, petroleum fuel can leak from subsurface storage tanks at gas stations; run off from landfills and spill from a train derailment can contribute to contaminant contents in the soil.

Possible signs of Vapour Intrusion:

  • Unknown chemical odour in the basement
  • Health issues (eye, throat and skin irritations; headaches, allergic reactions)

CASSEN Provides the testing of the following common analytical packages:

Hydrocarbons – Gasoline
Benzene Heptane m/p-Xylene
Cyclohexane Hexane o-Xylene
Decane 1,2,4-Trimethylbenzene Toluene
Ethylbenzene Isooctane
Hydrocarbons – Fuel Oil
Benzene Naphthalene m/p-Xylene
Ethylbenzene Tridecane o-Xylene
Toluene 1-Methyl Napthalene TVOC
Dodecane 2-Methyl Naphthalene
Hydrocarbons – BTEX
Benzene m/p-Xylene
Ethylbenzene o-Xylene
Chlorinated Hydrocarbons
1,1-Dichloroethane Tetrachloroethylene
2-Dichloroethane 1,1,1-Trichloroethane
1,1-Dichloroethene Trichloroethylene
1,2-Dichloroethene, cis- Vinyl chloride
1,2-Dichloroethene, trans-
CCME Petroleum Hydrocarbons (F1 & F2 – 8 Sub-Fractions) In Air
Aliphatic  Fractions Aromatic Fractions
CWS Aliphatic (>C6 to C8) CWS Aromatic (>C6 to C8)
CWS Aliphatic (>C8 to C10) CWS Aromatic (>C8 to C10)
CWS Aliphatic (>C10 to C12) CWS Aromatic (>C10 to C12)
CWS Aliphatic  (>C12 to C16) CWS Aromatic (>C12 to C16)
Naphthalene Benzene
Toluene m,p,o-Xylene
Ethyl Benzene

Vapour Instrusion

Conceptual Site Model of Vapour Intrusion—USEPA 2002
(Source: USEPA 2002) NAPL: non – aqueous phase liquid.


Other target compounds or packages are available upon request.