Indoor air and soil vapour evaluations are on the increase due to strengthening regulations and public awareness. EDI has completed numerous vapour intrusion & indoor air investigations, long-term environmental monitoring projects and developed risk assessment and management strategies for complex and high profile jobs. Due to the sensitive nature of vapour intrusion jobs EDI has consulted with Alberta Health Services and Alberta Environment and Parks to ensure public health is protected and works closely with our clients to minimize any inconvenience to the occupants.

Indoor Air Quality (IAQ) Assessments

We conduct basic indoor air testing to verify the general quality of the indoor air. Parameters included in the basic testing are usually dependent on the type of building occupancy. When a contaminant is suspected or confirmed to be present in the building, targeted indoor air testing can be conducted. In this case testing would focus on the chemical of concern and its direct by-products. Allowable Indoor Air Concentrations are developed in-house and calculated based on the current policy guidance. When buildings are located in the vicinity of sites contaminated with volatile parameters a vapour intrusion investigation is needed to evaluate whether the chemicals have migrated into the structure and determine if the building is safe for its occupants. If the air is deemed unsafe mitigation and a risk management program can be implemented or the occupants can be evacuated until the quality of air improves. Thorough indoor air testing is required prior to re-occupancy.

We also conduct indoor air complaint investigations. In the workplace good indoor air quality helps in providing a healthy environment for employees/staff. Problems with indoor air quality have become more common in the last decades due to energy conservation methods being implemented. Often the cause is improper air circulation which impacts air quality, therefore, an HVAC specialist should be contacted prior to starting an IAQ investigation.

Soil Vapour Evaluations

Soil vapour is defined as gas that occupies the pore space in the soil. On contaminated sites this pore space can contain volatile chemicals and is an important transport medium for the contamination. Soil vapour testing can be conducted as a part of the vapour intrusion investigation or as a stand-alone investigation. Sub-slab soil vapour testing is often completed in conjunction with a vapour intrusion investigation since it offers more information with respect to future patterns and can help to exclude confounders usually present in the indoor air.

Soil vapour testing is also conducted as part of supplemental investigations when previous assessments confirm the site has been impacted by volatile contamination. It can offer critical information in the development of a conceptual site model. Allowable Soil Vapour Concentrations are developed in-house and calculated based on the current policy guidance.