We were contacted by a company in London asking for an assessment of indoor air quality for the purpose of the BREAM assessment scheme. The objectives of this assessment were to;
Measure the concentration of formaldehyde in the indoor environment.
Measure the concentration of total volatile organic compounds (VOC) in the indoor environment.
Evaluate the site compliance against the BREEAM indoor quality requirements.
The site that we assessed was a 5-floor office building. The project consists of open-plan offices on each floor with a small number of private meeting rooms.
For more information regarding Formaldehyde & Voc’s click here
During the assessment the outdoor environment conditions were:
- Temperature: 23 Degrees Celsius
- Humidity: 54%
- Atmospheric pressure: 1012hPa.
At the time of the assessment each floor’s conditions was recorded:
- Fifth Floor: Temperature:22.5 Humidity: 59.4
- Fourth Floor: Temperature:21.5 Humidity: 59.1
- Third Floor: Temperature: 2.1.3 Humidity: 58.7
- Second Floor: Temperature: 21.2 Humidity: 63.4
- First Floor: Temperature: 22.5 Humidity: 59.8
- Ground Floor: Temperature: 21.8 Humidity: 59.8
- Lower Ground Floor: Temperature: 21.5 Humidity: 63.5
Sampling & Analysis
Volatile organic compounds (VOCs) and formaldehyde samples were collected via a Casella Gillian personal sampler fitted with TENAX anasorb thermal absorption tubes and glass tubes. Sampling flow rates were calibrated prior to and after sampling.
Samples of VOC were analysed by Thermal Desorption gas chromatography-mass spectrometry and the samples of formaldehyde were analysed by high performance liquid chromatography.
The requirements for indoor air quality are set out in the BREEAM HEA 02 document entitled “Indoor Air Quality” which states the following maximum limits:
Formaldehyde concentration in habitable rooms should be less or equal to 100 μg/m3 averaged over 30 minutes.
Total VOC concentration in habitable rooms should be less or equal to 300 μg/m3
over 8 hours.
|Lower Ground Floor||VOC||189.3||PASS|
|Lower Ground Floor||Formaldehyde||44.3||PASS|
Conclusions & Recommendations
The first-floor sample 9 exceeds the 300 μg/m3 indoor air quality limit. It is recommended to naturally ventilate the first floor to lower the VOC levels below the margin. It is in our opinion that the concentration of VOC in the affected areas has been reduced to blow the 300 μg/m3 by the time this report has been produced. The 16 days of natural ventilation between the sampling and completion of analysis would be more than sufficient to achieve indoor VOC levels below 300 μg/m3