Soil Gas Testing
Soil gas testing helps assess and reduce vapour intrusion by volatile chemicals.
Volatile chemicals can migrate from subsurface soils into overlying buildings by vapour intrusion. Soil gas testing helps organisations understand the impact of this exposure, enabling informed decision making to protect employees, the environment and resources.
SGS Soil Gas Testing Services
We employ both passive sampling and active sampling methods to assess subsurface gas contamination. Common methods include:
- Passive Sampling – sorbent media is left in the soil for a set period before analysis either by thermal desorption or by GC-MS. It is a simple and inexpensive tool used to gather site contamination data prior to spending large sums of money investigating soil and groundwater
- Waterloo membrane sampler:
- Simple and inexpensive for screening approach
- Used to assess large sites before targeted and costly investigations
- The passive sampler is then analysed for Volatile Organic Compounds (VOCs), TPH including BTEXN, NEPM Hydrocarbon Suites
- Radiello Passive Air Sampler:
- Does not require any electrical power and easy to install
- High and constant sampling rate – ideal for determining numerous gaseous concentrations. For each gaseous component there is a specific collection cartridge and sampling protocol
- High accuracy – detection limits range from 0.01μg/m3 to 0.1μg/m3
- Included in ISO 16200-2 method for the sampling and analysis of volatile organic compounds
- Conforms to the CEN/TC 264 WG 11 standard
- Considerable use in Europe and USA
- The Radiello passive sampler is then analysed for a wide range of chemicals like BTEX, VOCs, ammonia, phenols and cresols, anaesthetic gases, aldehydes, hydrogen fluoride, hydrogen chloride, hydrogen sulphide, ozone, ammonia, NO2, SO2…
- Active Sampling – sample is actively drawn. As environmental, health & safety professionals, you may need to access sampling and monitoring equipment for your projects. SGS can support with a network of equipment rental centres in North America. This service will be soon offered in the rest of the world at targeted depth
- Preferred method for vapour intrusion data, particularly for health-based risk assessments
- TO-15 Method – using negative pressure canisters
- Less complex sampling methodology
- Does not require power source
- Analysis using GC-MS with results presented in μg/m3
- Multiple analyses and high concentration samples can be diluted by transferring a small volume
- Standard analysis covers 62 compounds
- Capable of providing general gases data from the canister
- TO-17 Method – thermal desorption tubes
- Sorbent tubes that are packed with multiple beds of carbonized molecular sieve sorbents, separated by glass wool
- Target range of compounds, depending on sorbents used
- A range of sorbents are available to target compounds
- Analysis using GC-MS with results presented in μg/m3 (5 μg/m3 detection limit for a 1L sample)
- Low cost
- Standard analysis covers 56 compounds
Why choose SGS?
With over 6,000 environmental specialists operating in over 100 countries, we will help you choose the right soil gas testing system for your needs. Our experts understand the advantages and disadvantages of each system, meaning you get the level of accuracy you need to make informed decisions about controlling vapour intrusion.
Contact your local SGS office to learn more about soil gas testing services.