The health benefits of good ventilation

Patrick Calvey of Siegenia looks at the issue of air pollution and the considerations designers of new facilities and refurbishments need to make in order to combat it

The effects of air pollution and the dangers of exposure to NOx particles in particular have hit the public consciousness in recent months and with the risks to heart and cognitive health becoming ever clearer, ventilation is increasingly becoming a priority when building or renovating public facilities, especially healthcare establishments. Last summer a study on the effects of NOx particles on the heart by Queen Mary University of London made the headlines. The study of 4,000 people in the UK found that changes to the structure of the heart occurred even when exposure to NOx was less than the UK legal limit. Other recent studies carried out in China and London have also suggested that air pollution can have a negative effect on cognitive intelligence, and that it can increase the risk of developing dementia in the over 50s. While many healthcare sites across the country, as part of the Carbon Reduction and Sustainable Development Strategies, have implemented green measures which will reduce air pollution levels in the vicinity, there remains the problem of indoor air quality.

Far from providing respite from the outdoor air, a study by the US Environmental Protection Agency has found that indoor air pollution is often between two and five times greater than outdoors ­– and can reach up to 100 times greater – as pollutants entering from outside are added to the CO2 and VOCs (Volatile Organic Compounds) indoors. Poor indoor air quality can have numerous detrimental effects including worsening asthmatic symptoms, headaches and loss of productivity. Poor air quality in the workplace has even been found to be the cause behind 800,000 premature deaths per year, according to The Lancet. In order to provide a healthy indoor environment for staff, patients and visitors it is therefore important that planners make indoor air quality at least as great a priority as outdoor air pollution has been.

The benefits of mechanical ventilation units

The best way to address poor indoor air quality is to introduce a mechanical ventilation system into the building. Mechanical ventilation provides constant fresh air and, unlike natural ventilation methods such as the opening of windows, modern mechanical systems can filter out pollen, carbon, coarse and fine dust and NOx particles. These systems are therefore a much better means of tackling indoor air pollution and minimising the associated health risks. Up to now, natural ventilation has often been favoured in healthcare facilities due to the perceived energy and cost savings. However, decision makers should consider the lifetime costs of mechanical as opposed to natural ventilation. Modern ventilation units require very little energy to run, some using as little electricity as a TV on standby. They can also provide savings elsewhere.

For example, the provision of fresh air in the colder months means that windows do not have to be opened and heat wasted. Furthermore, the sustained provision of fresh air can help to prevent damage to the building structure and windows caused by damp and mould, thereby decreasing future maintenance costs. There are also the aforementioned health co-benefits, as the provision of filtered air reduces the risks to patient, staff and visitor health, therefore lowering the future burden on the NHS. By protecting the health of both the buildings and inhabitants, ventilation systems can provide ongoing savings which offset the original outlay. Mechanical ventilation need not be expensive or time-consuming to install.

Planners are often put off by centralised systems, which require ducting throughout the building; however simple single unit versions are also available on the market and can be just as effective. These can take as little as 45 minutes to install, requiring only a core drill hole in the wall for the pipe and a couple of screw fixings for the unit. Maintenance also does not need to be a costly job. Some filters need only be cleaned or replaced once a year and units are available that will indicate this. If the right system is chosen, mechanical ventilation should provide a net positive impact on the environment and on health, improving not only environmental but also economic sustainability with net savings across the lifetime of the system.

Patrick Calvey is sales manager at Siegenia