N-95 masks protect users, not those around: Experts

CAUTION Valves could act as easy passage for germs and endanger those in proximity N-95 MASKS WITH VALVES MASKS WITH NO VALVE

nNEW DELHI: People using N-95 masks with respiratory valves may be protecting themselves, but those around them could be at high risk of contracting an infection, according to experts who recommend the use of face covers without valves in a viral outbreak such as the coronavirus disease (Covid-19) pandemic.

Using N-95 masks with valves is recommended when pollution levels are high as they do not allow carbon dioxide to accumulate inside, experts said. But the same valve — used for exhalation — could act as an easy passage for germs and endanger those in close proximity if user has an infection. “If you’re using N-95 masks, use those without a valve,” said GC Khilnani, a member of Delhi CM’S advisory committee on Covid-19 preparedness and chairman, PSRI Hospital New Delhi.

While all masks filter air users are inhaling, ones without valves also trap most germs coming out with exhalation, protecting people around those wearing them.

The Union health ministry has been issuing regular advisories, asking people to avoid wearing N-95 masks, which are used as part of personal protection equipment (PPE) kit for health care and other frontline workers dealing with Covid-19 cases.

Harsh Mahajan, owner of Mahajan Imaging, a diagnostic centre, said N-95 masks should be prohibited even for health care workers. “In fact, in Covid times, N-95 masks with valve should be banned as these are meant to be used during high pollution levels...valve meant to breathe out air will also let germs (viruses and bacteria) pass, making it unsafe for others in close proximity. Purpose of wearing a mask to protect others will get defeated in the time of Covid-19,” he said.

Khilnani said it is important to

Experts say N-95 masks with valves — effective when air pollution levels are high — puts those around users in risk during a pandemic

WHAT’S AN N-95 MASK? wear a mask in way it covers the face snugly from upper part of nose to chin. “If you use washable masks, wash, dry and reuse after five days...surgical masks should be disposed of after every use.”

Surgical masks are recommended by World Health Organization for health care and sanitation workers not directly involved in dealing with Covid patients. These masks create a barrier around nose and mouth, but such face covers should be discarded after each use. Another option is a homemade face cover (preferably made of cotton fabric) that can be reused after washing.

SK Chhabra, a senior pulmonologist at Primus Hospital in New Delhi, said: “For healthy persons stepping out, face covers should provide some protection as these will stop exposure to bigger droplets. However, use of handkerchiefs or stoles should be avoided as there will be too many leak points.” Only cotton should be used to make masks, he said. “Apart from not being virusfriendly, cotton is also a breathable fabric. Chances of the face cover not getting wet easily are higher in cotton-made covers. Once it gets wet you have to replace it; otherwise, it isn’t effective. Nylon ones serve no purpose,” Chhabra added.

Cotton-made face covers are recommended for healthy people or those with flu-like symptoms who are stepping out. But face masks don’t provide 100% protection and should be used while maintaining hand hygiene, cough etiquettes and physical distancing. Gloves too are important, and need to be regularly disinfected even while wearing. “Gloves are usually disposable and must be discarded after single use,” said Srikant Sharma, a senior consultant at department of medicine, Moolchand Hospital.