N 95 respirator

Subject: Science and tech

Context:

The Union Health Ministry cautioned against the use of N-95 valved respirator/masks as it does not offer the desired protection against the spread of COVID-19.

Concept:

• The evidence which suggests that with a valved mask the person wearing it is safe but if they are COVID-19 positive or asymptomatic, then propensity of that person infecting others is there.

Source: The Hindu

• An N95 respirator is a respiratory protective device designed to achieve a very close facial fit and very efficient filtration of airborne particles
• N95 mask named because it is able to block at least 95% of particles in the air that are of the size 0.3 microns or bigger (1 micron is a millionth of a metre).
• A single SARS-CoV2 virus is typically up to 0.2 microns in size, so it can possibly penetrate the N95 mask.
• N:This is a Respirator Rating Letter Class. It stands for “Non-Oil” meaning that if no oil-based particulates are present, then it can be used in the work environment.
• Other masks ratings are R (resistant to oil for 8 hours) and P (oil proof).