Hospital indoor air quality

Health and Wellbeing and Indoor Environmental Quality in Buildings – A Guide to BS 40102-1:2023

BS 40102-1:2023 – Health and Wellbeing and Indoor Environmental Quality in Buildings is a new code of practice which launched in April 2023.

In this post we’ll explain what BS 40102-1:2023 entails and discuss how you can meet the new regulations in your workplace.

What is BS 40102?

This new code of practice outlines a monitoring and reporting strategy for assessing wellbeing and indoor environmental quality (IEQ) of non-domestic buildings. It establishes a rating system for benchmarking the quality of the:

  • Air
  • Light
  • Thermal comfort
  • Acoustics and soundscape

With these benchmark scores, facility managers can identify any problematic areas and make any necessary improvements.

BS 40102 applies to all forms of non-domestic buildings, existing or new.

Why Has ‘Health and Wellbeing and Indoor Environmental Quality in Buildings’ Been Introduced?

The BSI Group acknowledges that previous regulations, coupled with certain commercial pressures, encouraged designers, builders, and facility managers to prioritise energy efficiency. All too often, a focus on energy efficiency means that the health and wellbeing of a building’s occupants gets overlooked. For instance, a building might be constructed with efficient insulation, but with little thought given to the quality of ventilation and light levels.

These new standards will help facility managers and others improve the IEQs of the buildings they oversee. Improving IEQ can help reduce operating costs through increasing energy efficiency. But for hospitals and other healthcare settings, addressing IEQ can help improve staff and patient health and wellbeing while contributing to infection prevention and control.

BS 40102 Air Quality Standards

When it comes to air quality, BS 40102 outlines rating systems for:

Example Indoor Environmental Quality Benchmarks

Below are the BS 40102 rating systems for two forms of particulate matter – PM2.5 and PM10.


Level Description 24 Hour Average (μg/m3)
0 Very High ≥32
1 High 16 – <32
2 Acceptable 10 – <16
3 Low 5 – <10
4 Very Low <5



Level Description 24 Hour Average (μg/m3)
0 Very High ≥68
1 High 46 – <68
2 Acceptable 30– <46
3 Low 10 – <30
4 Very Low <10


How Cairn Technology Can Help You Meet BS 40102 Regulations

We can measure the air quality throughout your healthcare setting and monitor your staff’s exposure levels to any potentially harmful substances. As well as the hazardous pollutants covered by BS 40102, we can also test for levels of sevoflurane, isoflurane, Entonox, and more. This will help you understand your risk levels so you can devise an air quality solution that works for you. Head here to learn more about our bespoke air quality monitoring services.

We also stock a range of specialist air purification systems. Our Blueair HealthProtectTM  air purifiers are fitted with advanced HEPASilent technology. This is capable of catching 99.97% of particles down to 0.1 microns, including PM2.5 fine air particles, as well as VOCs, dust, mould, and up to 99% of viruses and bacteria. Browse our full range of hospital grade air purifiers.