An introduction to indoor air quality
30 March 2022
AIR QUALITY is one of the most significant health challenges of our time. Repeated exposure to air pollutants is one of the top potential causes of chronic health problems such as lung cancer, cardiovascular disease and respiratory infections.
According to the World Health Organisation (WHO), in 2016 air pollution was linked to over 4.2 million deaths per year, accounting for 11.6% of all deaths worldwide.
The quality of indoor air (IAQ) is often overlooked but it can affect people’s health as much as the more obvious outdoor ‘pollution’. An average person spends up to 22 hours a day indoors, so it is essential to ensure IAQ meets ongoing sustainable health objectives.
IAQ refers to the indoor air that circulates throughout the environment we work and live in. IAQ can be affected by: Microbial contaminants (i.e., mould and fungus) which depend on the temperature and humidity conditions of a room; gaseous pollutants (including carbon monoxide, carbon dioxide, volatile organic compounds (VOCs) etc); dust particles or aerosols.
There are many sources of indoor air pollution, including common cleaning products, air fresheners, aerosols, fuel burning appliances and even carpets, paints and building materials. On their own or collectively, these pollutants can all cause adverse health effects to occupants ranging from fatigue, headaches or eye, nasal and skin irritation through to asthma, COPD and even lung cancer.
Health-based ambient air quality standards are set at levels of pollutant concentrations that would result in adverse impacts on human health, so strategies, technologies and regulations are all developed with the aim of achieving a reduction in exposure.
Air Quality monitors use two main methods of monitoring and analysis:
- The Gravimetric method uses a cassette to collect a dust sample, which is then sent to a laboratory for analysis. This is an accurate method which can be used to speciate. However, there is a delay between taking the sample and receiving the analysis.
- Real-time air quality monitoring uses devices with laser photometer technology to count real-time concentrations of dust in different PM sizes e.g. PM10, PM4, PM2.5 & PM1.
Personal monitors are programmed to trigger visual and audible alarms to alert the user when concentrations have exceeded pre-set thresholds. In area monitoring applications, data is also often sent to and stored in the cloud, to be accessed and downloaded remotely. With cloud real-time monitoring, it is now possible to create a network across a large area to document contaminant levels. This information is often used to support a reduction strategy or to show that an air quality standard has been achieved.
Instruments are often calibrated against a standard test material commonly known as Arizona Road Dust, which is a good approximation of most ambient aerosol particles. Calibration factors allow for more accurate measurement of specific aerosols, as calculations are based on the properties of the specific compound being sought.
For example, if the user is looking for cadmium, a custom calibration can be entered into a device, allowing for a highly accurate, very specific real-time measurement to be taken.
At Shawcity’s in-house service & calibration centre, we can prepare a custom Calibration Factor for specific aerosols that have different properties to the standard test dust. Contact our Service Team to discuss your individual requirements: email@example.com
Shawcity offers an extensive range of real-time air quality monitors available to hire or buy, along with free unlimited technical support. From indoor monitors that measure particulate, smoke, fumes, mist, gas and VOCs through to outdoor environmental monitoring for temperature, humidity, PM1.0, PM2.5, PM10 and PMTotal, we will provide the right solution.
Contact our friendly team to discuss your requirements.