Indoor air quality
Assessment and evaluation of indoor air quality
Indoor air quality has a major influence on the health, comfort and well-being of building occupants. Poor air quality has been linked to Sick Building Syndrome, reduced productivity in offices and impaired learning in schools.
As people in Europe spend at least 90% of their time indoors, their total exposure to many air pollutants largely depends on their indoor exposure. These pollutants include volatile organic chemicals (VOCs), gases such as nitrogen dioxide, ozone and carbon monoxide, particulate matter and fibres, and biological particles such as bacteria, fungi and pollen.
Pollutant sources include outdoor contaminants from traffic and industry, which enter buildings by infiltration and through ventilation systems, and indoor contaminants from burning fuels, candles and tobacco, and emissions from building materials, furnishings, cleaning products, electronic equipment, toiletries, people and pets. New building products can be particularly important pollution sources.
Pollutants' impacts on health depend on their toxicity, concentration and exposure period, and range from odour to irritation to serious toxic effects. The 2006 revision of the Building Regulations concerning ventilation (ADF) set performance criteria for several air pollutants, including VOCs, nitrogen dioxide and carbon monoxide.
The control of pollutants depends on both tackling their sources and having adequate ventilation with 'fresh' outdoor air. BRE is actively involved in writing international standards for the measurement and control of indoor air pollutants. Our services are based on extensive experience in this area and include:
Evaluating indoor air quality in homes, offices, hospitals, schools, etc. We undertake a wide range of measurements and carry out sampling and analysis within an accredited UKAS framework.
Measuring air exchange rates in buildings and advising on remedial actions.
Advising on appropriate mechanical ventilation systems and evaluating the performance of air cleaners (see our HVAC pages for more information).
Dealing with ground contaminants - soil gases entering buildings from the ground are important pollutants at many UK sites. These include radon, a carcinogenic gas occurring in some regions, landfill gases that can be explosive hazards near waste sites, and chemical vapours that can occur where former land use has caused ground contamination. BRE evaluates the impacts of ground contaminants on indoor air quality and assess risks to health.
Assessing other indoor environments such as aircraft cabins, motor vehicles and trains.
Case Study: Greenwatt Way, Slough
A £3.5 million development of ten homes in Slough, which was designed to Code for Sustainable Homes Level 6 and launched in September 2010 by Scottish & Southern Energy (SSE), will undergo a series of performance tests by BRE as part of a jointly funded SSE and NHBC Foundation research programme.
The Greenwatt Way development will be tested for airtightness, ventilation rates and indoor air quality. The homes’ mechanical ventilation with heat recovery (MVHR) systems will be monitored, and a post-occupancy evaluation of inhabitants’ behaviour and experiences will be carried out.
‘In order to meet energy requirements, homes built to the upper levels of the Code for Sustainable Homes have to be very airtight,’ says Dr Andy Dengel, an Associate Director at BRE, ‘and typically feature MVHR systems to manage a healthy airflow in the home. BRE’s tests on Greenwatt Way will provide a very useful evidence base of information on the air quality and thermal conditions in these houses, the effectiveness of the MVHR systems, and the occupants’ response to the technology – which will in most cases be outside their normal home experience.’