Haryana PWD advises against use of ACs in offices to prevent Covid-19 spread
An advisory issued by PWD states that Covid-19 spreads due to droplets and when these droplets mix with dust particles and set on different materials, they become all the more infectious.Updated: Apr 29, 2020 15:33 IST
In view of chances of spread of coronavirus in an air-conditioned environment, the Haryana government on Tuesday recommended that air conditioning should not be used in offices or used restrictively.
An advisory issued by the public works department (PWD) after consultations with the health department stated that Covid-19 spreads due to droplets and when these droplets mix with dust particles and set on different material, they become all the more infectious.
“If the environment of an area is cool and air conditioned, the virus remains there for a longer time. Proper ventilation and increase in temperature reduces the magnitude of virus spread in that particular area. So, air conditioning should be used under strict restriction when absolutely needed. Open window gives better ventilation and is very effective for controlling the transmission of disease. Hence, it is recommended that air conditioning should not be used in offices or be used very restrictively,” said the advisory.
It is advisable not to operate centralised air conditioning system in the present scenario because even if the return air ducts are closed, contamination can spread within the room as office spaces are occupied by multiple persons.
Allow natural or mechanical ventilation in hospitals
The PWD has recommended to keep the central air conditioning system non-operational in healthcare facilities and allow natural ventilation by opening windows and doors in quarantine and isolation wards, morgues, waste zone, screening and triage area, staff area, waiting rooms in hospitals. It also recommended mechanical ventilation by using exhaust fans in sampling room, severe and critical cases wards.
“In district hospital, where there is sufficient space, natural ventilation should be allowed. Isolation facilities should have large windows on opposite walls of the room allowing a natural unidirectional flow (top to down) and air changes. The principle of natural ventilation is to allow and enhance the flow of outdoor air by natural forces such as wind and thermal buoyancy forces from one opening to another to achieve the desirable air change per hour,” the communication said.
Keep ACs on in vacant rooms only
The advisory said that for residential use, fans should be operated with windows kept partly open. If an exhaust fan is located at a nearby location, then it must be kept running to exhaust air for better ventilation.
Desert coolers are useful in drawing air from outside to ensure good ventilation and windows must be kept open to release the humid air. Portable room coolers that do not draw air from outside are not recommended.
Room ACs (windows and split) should be switched on in a vacant room in the absence of people to cool the premises. However, they should be switched off on arrival of people. Ceiling fans should be kept running. Adequate ventilation must be ensured by opening the windows, the advisory said.