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HVA
VAC in schools
Chemicall y cleaner C
oncerns over the quality of air in public buildings have gained increasing media coverage during the past two years, with particular scrutiny of spaces accommodating vulnerable occupants such schools.
In July 2016, a study from environmental consultancy Aether revealed that secondary pupils at 86 London schools were exposed to dangerously-high levels of air pollution in 2013.
In 2010, the same year that a report revealed 433 primary schools were in breach of EU nitrogen dioxide (NO2) pollution limits, 5,900 deaths in the capital were attributed to long-term NO2 exposure. The inhalation of NO2 is known to aggravate respiratory problems such as asthma, bronchitis and emphysema. In September 2017, an FIA Foundation report (‘London’s Polluted Schools: the Social Context’) found that 20% of schools in London are situated in areas blighted by poor air quality.
The study also highlighted the link between exposure to polluted air and poverty, with the greatest number of primary schools affected by toxic air being in an area with a deprivation score of 35-40 (the average being 23.6). The figures for secondary schools followed a similar pattern, with more than 30 falling in the 35-40 deprivation score bracket.
Young people are at greater risk from air pollution than adults because their lungs and immune systems are still developing, plus they tend to breathe at a faster rate and inhale more air. The fact that schools are often sited on busy roads means that traffic pollution is a significant factor in what London Mayor Sadiq Khan has described as a “national air quality health crisis.”
Outdoor air pollution means that many schools depend upon heating, ventilation and air conditioning (HVA
VAC) systems to provide safe, clean air to staff and pupils.
Gibbons Ultraviolet Solutions manager Colin Hardman says: “Sadly, maintenance of these systems is often inadequate or overlooked entirely, leading to the development of mould, bacteria and viruses within the air handling unit (AHU) and ductwork. These contaminants are then introduced to classrooms via the airstream, leaving students and staff at risk of infection.
“Poor indoor air quality (IAQ) not only poses physical health risk s;
schoolchildren exposed to airborne pollutants may experience headaches and tiredness, leading to difficulty in concentrating and increased absenteeism. “A permanent solution to the challenge of maintaining HVAC hygiene is the treatment of AHU and ductwork surfaces with ultraviolet-C (UVC) light. UVC light is powerful enough to virtually eliminate biofilm, while continued application prevents the regrowth of such contaminants.
“UVC light works by disrupting the DNA of biofilm, preventing cell reproduction and eliminating cells altogether with continued use.
“Additionally, by permanently cleaning ductwork with UVC light-emitting lamps, AHU performance is improved, which increases energy efficiency and extends operational life. A major benefit of UVC systems is that they can be modelled to fit almost any system, making them ideal for both new and retr ofit installations. Running costs are low, and the efficiency gains from removing contaminants means that the initial outlay can be recouped in energy savings within a matter of months in some cases.”
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