International News
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contain extensive tables and lists of tests and inspections that should be regularly performed on all ventilation components and equipment by registered , suitably qualified persons .
As many worldwide studies have shown , thermal comfort and indoor air quality have a considerable impact on general wellbeing , as well as on people ’ s levels of concentration and efficiency , not least in offices . These studies have demonstrated that , for instance , where temperatures or humidity levels are too high or too low , and considered to be uncomfortable , or if the air quality is inadequate , performance and concentration levels can quickly dip by 5 to 10 %.
As from the beginning of 2016 , the efficient operation of ventilation units has been prescribed by the implementation of EU Regulation 1253 / 2014 on the “ ecodesign requirements for ventilation units ”. This regulation specifies , for example , the use of heatrecovery systems and air filters , which entail maximum permissible electricity consumption for the fans used . All companies in the EU , that manufacture or supply ventilation systems , must observe and document these requirements .
Experts agree that the Covid pandemic , which has persisted since the spring of 2020 , and the need to protect people from being infected by the coronavirus in enclosed spaces is going to have a major impact on ventilation and air-conditioning technology . Ventilation units play an important role here , as constant flushing of indoor spaces with large volumes of clean external air will significantly reduce the concentration of Covid aerosols in room air and thus greatly limit the risk of infection . In effect , the more external air that is used , the better the effect .
And if the existing ventilation system is not powerful enough to provide an exchange of air from the outside sufficient to provide a significant reduction in Covid aerosols , two further measures are recommended :
Firstly : windows should be opened at regular intervals to provide ventilation . Secondly : supplementary air-purifying units should be set up and operated . These plug-in devices continually suck in the room air , filter out any viruses that it may contain using high-efficiency , particulate filters ( HEPA ) and / or UV-C irradiation and then return the purified air into the room .
Efficiency levels of over 99 % can be achieved . Such devices , which are also recommended by virologists as a sensible additional measure to complement the introduction of external airflow are now available from many manufacturers , with a variety of designs and airflow levels . They are suitable to provide effective supplementary protection from coronavirus infection in , for example , classrooms , open-plan offices and conference rooms , as well as in doctors ’ surgeries , fitness rooms and other similar applications .
At the same time , we can assume that the coronavirus pandemic and the need for personal protection will , in future , be given greater consideration in the planning and installation of ventilation and air-conditioning systems – with , for example , higher airflow volumes and the use of highefficiency air filtration systems . Detailed information about ISH digital can be found at the official website . RACA
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