Continuous indoor air quality monitoring: What this means for ground gas risk assessment

25Oct / 2018

Continuous indoor air quality monitoring: What this means for ground gas risk assessment

When site development is close to completion, continuous indoor air quality monitoring can bring another line of evidence that is easy to understand and interpret, especially if there are doubts on the effectiveness of ground gas protection measures.

Maintaining good indoor air quality in a building is critical for ensuring a safe, comfortable and habitable environment for its occupants. One of the many causes of poor, and potentially hazardous, indoor air quality includes ground gas entry through the floor structure and service penetrations. Different ground gases pose different health and safety risks. It is therefore important to identify the ingress to apply appropriate corrective measures that guarantee excellent indoor air quality.

ggs indoor air quality

Figure 1 Continuous indoor air quality monitoring instrument in situ.

When is continuous indoor air quality monitoring suitable?  

On most sites where ground gas ingress is a concern, continuous monitoring of the sub-floor void can be performed to identify the hazards to a building. However, in some cases, a sub-floor void is not present in the building design, and therefore monitoring the indoor air quality is the best alternative.

Once the indoor air quality parameters have been assessed, the results can be examined to identify if any ground gas has entered a building. If this has occurred, the appropriate measures can then be applied to mitigate the ground gas risk.

Continuous indoor air quality monitoring can help demonstrate that an existing building or protection measure are appropriately mitigating ground gas ingress to a building. It also allows for “worst-case scenario” events, such as a rapid fall in atmospheric pressure, to be captured and identified during a relatively short monitoring period.

How can GGS help?

The latest instruments used by GGS, including the Gas Sentinel®, can continuously monitor indoor air quality at high resolutions. They are also compact and can be comfortably deployed within any building without causing unnecessary disruption. These industry leading devices are housed within a robust and secure box to protect from damage during the monitoring period (See Figure 1), thus providing a discreet service and a practical solution to many sites where access and security are difficult. GGS also offers insurance to clients for instrument damage or theft so there won’t be any hidden additional fees for replacing the equipment.

GGS engineers are extensively trained and experienced in deploying air monitoring instruments in a variety of settings. Quick decision making on site by our staff often saves our clients time and money, with quicker response times to issues identified on site. High-resolution hand-held devices are used to undertake gas sweeps of buildings to assist the selection of appropriate continuous monitoring locations. Our standard service includes deployment, maintenance and collection of the equipment on site, so if anything goes wrong, we’ve got it covered with no additional hidden fees.

The continuous monitoring data is processed and presented in our market leading graph format to aid interpretation (See Figure 2). This makes it easier to identify the significant relationships between indoor air quality and environmental parameters and provides confidence when identifying any ground gas ingress into a building.

Figure 2 Continuous monitoring results including atmospheric pressure (top), oxygen concentrations (middle) and high-resolution methane and carbon dioxide concentrations (bottom).

With almost ten years of continuous monitoring and risk assessment experience, GGS is the only specialist company that can provide a complete service from instrument deployment, data processing, factual reporting to, when required, full risk assessment and outline remedial design.

Our new fleet of GasSentinels® with high resolution sensors have further enhanced our capability. We provide accurate data and evidence to our clients to ensure that appropriate ground gas protection measures are installed in developments where they are needed. The upshot to this is that through high quality monitoring and risk assessment, expensive retrospective protection measures are avoided on those sites where they are not needed.

GGS’ reputation for reliably delivering a high-quality service, underpinned by continuous innovation and market leading technology, ultimately means that our clients save time and money. Adopting continuous indoor air quality monitoring is further evidence of the company’s commitment to continuously improve its service to its clients.

GGS’ continuous monitoring services can help you: 

  • Reduce risk
  • Avoid expensive corrective measures
  • Speed up planning and building control approval
  • Provide time and cost savings