Hacker News Reader

Comment by thesimp | Hacker News Reader

Are there masks for sale then? Here in The Netherlands there are no n95 masks available for the average person. I understand that hospitals and 1st aid responders need them now, but in the short term I would like to be able to get some.

View on HN

JFYI, the N95 masks are NOT intended for the average person anyway. (in EU they are called FFP2/FFP3)

They need face fitting and some basic usage instructions.

If not correctly fitted they won't be effective, as air (like in more common "surgical" masks) will enter (and exit) from the sides.

They still help, but they help less when not used correctly. The average person likely won't use them correctly. This makes it a waste to give average people these masks when there's a shortage.

These masks are fairly standard consumer use in the UK for various DIY activities in the home and supplied by hardware stores as such. Note P3/FFP3 are higher standards than N95.

They are just fine if the idea is to protect oneself from dust, but here we are talking of protecting from a virus (and to protect others, so valved masks are not suitable).

Rough correspondence:

FFP2 is 94%

N95 is 95%

FFP3 is 99%

Source (an UK firm):

http://www.ashsafety.com/tips/filterClass.htm

> Finding a suitable respirator is not just a matter of choosing a model you like or by the cost of it. You may need to try different makes or sizes to find one that fits without leaking around the seal and letting dust in. A respirator that depends on face fit is ineffectual if you have a beard or thick beard stubble. The only way you can know if the seal is good enough is by having a proper respirator fit test. At present this is also the only way of meeting legal requirements.

And here is (again UK firm) how a fitting test works:

https://www.xamax.co.uk/blog/how-to-respirator-face-fit-test...

Supermarkets will be providing surgical masks (not N95) free of charge. In places where none are available, use will not be mandatory at this point (though strongly recommended).

Are n95 masks considered basic? I would think a basic face mask refers to something like a surgical mask, which doesn't protect the wearer but protects others from getting infected by droplets from the wearer.

Surgical masks are pretty good at protecting the wearer from droplets too. It's the fine aerosols where they're much worse than a surgical mask stopping maybe 80% of virus-sized particles where N95 masks tend to stop 99%+.

EDIT: Remember, though, that you can still be infected through exposed eyes, having virus on your hands and touching your face when taking off the mask, etc. Also, there was some evidence for rare cases of what looked like aerosol spread with the original SARS. In his recent interview on This Week in Virology Ian Lipkin mentioned a study in Beijing in the SARS outbreak where people with consistent mask use saw infections Ian Lipkin by 70% compared to no mask use. That's good but it isn't immunity.

>95%, which is why they are called N95.

They're guaranteed to stop 95% of the hardest to stop particulates which actually tend to be somewhat larger than viruses.

Yes, i was correcting you on your statement of 99%+. Its >95% of 0.3 micron particles, but as coronavirus is smaller it would be LESS than that - not more).

Looks like you're right surgical masks does give the wearer some protection.

Prior to this crisis, N95 masks were the cheapest, most basic respiratory protection you'd find in a DIY store. Pack of ten for $20, between the sandpaper and disposable earplugs.

Perhaps due to poor fitting, they were also seen as questionably effective and prone to making your safety googles fog up.

The article talks about mandatory masks, i.e surgical masks, for shoppers, to reduce spreading by shoppers.

No N95 masks needed, those are needed for healthcare workers (and need to be replaced very frequently).

You most certainly:

don't need it

would reduce the amount available for people that need it

would wear it wrong

would wear it too long

touch it with your hands

would get a false sense of safety

Reply on news.ycombinator.com