Following the reblog of On the 14th Day comes these scribbles of mine.
They are all about breathing what you shouldn’t i.e. Contaminated Dust and in particular fallout and the reason why I frequently remind people to don a filter mask to FFP3 or P100 as you can always wash dust off but you can’t wash out your lungs.
Particle Size is the danger here only what sizes are we talking about?
TINY! Below what is visible and the average eye can just about see 50 microns.
Very small particles may be inhaled and enter the deepest regions of the lungs.
This is where the aleoli ‘live’. That’s the little air sacs in your lungs where blood is close enough to exchange gases within it to the air. There is also 30 to 100 SQUARE METERS of them and they have a thickness of only 1 cell.
What size of dust are we talking about? 0.4 microns. 0.015748 thousandths of an inch.
As particle size increases to about 10 microns and above, the dust is too big to enter the aleoli. Still too small to be seen, they usually stick in the upper respiratory tract.
This stuff can be cleared by violent coughing. Even larger stuff than that won’t pass nasal hairs .
Anyway donning a mask will help your long-term survival chances a lot.
They come in all sorts of grades and styles but I’m only interested in the fold flat types.
The ones I carry as part of my basic PPE.
It is said that the worse size for these masks to handle is 0.3 microns and that is what they are tested to.
In the UK they are rated FFP 1 to 3.
FFP3 has a filtering efficiency or 98%
In the US they are rated by NIOSH letter and number.
P-100 are fully resistant to liquids and oils. 99.97% Efficient
How good is a FFP3 or P100 mask?
They can filter 99% of all particles .3 microns or greater
No one has ever claimed that face masks are ever 100% safe and they aren’t.
Don’t ever think they are BUT they will help in a “dusty” environment.
Other things to watch out for include your eyes..
Naturally wet and thus a magnet for dust, you need to keep them covered as well.
Here are a few examples to look at in the way of protective equipment for eyes.
In order the protection:-
- Safety glasses aren’t much good at stopping driven fine dust.
- Eye pads fit inside most glasses and form a fair to good dust barrier which is good
- Swimming glasses rate about the same only, unlike eye pads, they won’t fit on prescription glasses. So if you are visually impaired at all they afford less protection.
- Safety goggles. The only type that work reasonably well is those with indirect ventilation. The advantage is some designs will fit over prescription glasses.