The centre on Friday said the ideal temperature that should be maintained while operating a domestic air conditioner amid the coronavirus pandemic is between 24-30 degree centigrade. Issuing an advisory regarding the use of ACs in homes and offices, it said the relative humidity must remain between 40-70 per cent.
The guidelines compiled by the Indian Society of Heating Refrigerating and Air Conditioner Engineers (ISHRAE) were shared by the Central Public Works Department (CPWD).
In preparing the document, a COVID-19 Task Force extracted, examined and analysed information related to the climatic conditions of the country. The team comprised members from academia, designers, manufacturers, service providers and experts related to sciences such as filtration, healthcare facility design, and indoor air quality safety.
“Recirculation of cool air by room air conditioners must be accompanied by outdoor air intake through slightly open windows and exhaust,” the document suggests.
“In dry climates do not allow the relative humidity to fall below 40 per cent. Water evaporating from a pan kept in the room will increase humidity if it falls below 40 per cent,” it added.
The panel suggests that the rooms should be kept ventilated even when ACs are not running. “As an extra precaution the frequency of service can be increased,” it said.
The guiding document further said windows should be partly kept open while using electric fans. “If an exhaust fan is located nearby then it can also be switched on to exhaust air for better ventilation”.
For commercial and industrial facilities, the document recommends ventilation with outdoor air as much as possible. “The mechanical exhaust air shall be 70-80 percent of the fresh air quantity to maintain necessary positive pressure in the space,” it said.
“Most commercial establishments have remained closed during the lockdown. These establishments will need maintenance for both engineering and health safety. The air-conditioned spaces of establishments under prolonged lockdown will pose health hazards due to fungus and molds in the ducts and open spaces depending on the humidity and temperature prevailing within. Further there may be bird droppings, and excreta of rodents as well increased level of insects,” the advisory added.