Broken 3M Aura Strap - How SOL Are You?
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- Опубліковано 25 сер 2024
- 3M Aura 9205+ N95s are awesome, but sometimes the straps spontaneously break. I tested how badly the mask leaks when a strap breaks to find out if you are totally SOL or not when that happens.
In the video I test:
00:32 A new Aura mask as a control for comparison
01:20 An Aura I've used on and off for about 3 weeks
03:03 The 3 week old Aura with the top headband broken
I'm using a PortaCount fit testing machine that gives scores in "Fit Factor".
Fit factor is the the concentration of particles outside the mask divided by the number inside the mask. So if there were 100 particles outside and 10 inside, 100 divided by 10 is 10, so the air inside the mask is 10 times cleaner and the fit factor is 10. If there are 100 particles outside and only 1 inside, the mask would be a 100x cleaner inside, for a fit factor of 100.
You can buy 3M Auras at Home Depot and at Amazon (buy Ships and Sold by Amazon to in sure you get real ones). They are very good masks that filter very well and comfortably fit a wide variety of people, more so than the old cup style masks like the 8210. For me they are a game changer.
I wonder if a broken bottom headband would yield a better fit factor, though I imagine it's usually the top one that gets stretched out and fails first. Great video. Thanks!
I'm not sure. I think it might depend partially on the shape of one's face. I think the crown strap may be the most important, but I accidentally wore an aura with just one strap around my neck, and I couldn't figure out why the chin was so loose until I felt that there was no strap over the top of my head. I had just forgotten to put the top strap on. The nose fit was just fine, but the chin may have leaked. I don't know if that would make for a bigger leak and if a test or not.
I do have another aura with a strap that broke spontaneously, this one broke at the bottom strap, again, right near the staple but not directly under it. I considered adding it to the testing for this video, but I didn't want to make the video too long. I don't really have a good feel for how much people will put up with in terms of length, and I haven't really mastered the art of making short pithy videos, such as are required for TikTok or Facebook reels.
@@gerardhughes You're doing great so far! I think the length is perfect - not too short, not too long.
I was wondering about something similar. If the top strap breaks, does it make sense to adjust the bottom strap to the top strap position? Likewise, if one of the straps fails, can you buy elastic band used for clothing and use this instead? (a possible DIY solution for those with less money available?).
Has definitely happened to me on several occasions, also with the 3M 8210s. The breakage is accelerated also because I have glasses that seem to create friction on the straps. I've moved solely to the 9210+ for the fabric straps.
Thanks for providing these videos, much appreciated. Do you have a website with a summary of your findings? If not, would be great to see summaries at the end of each video. Keep up the amazing work!
Is it quite fair to call it failure "without warning" when you have been storing a rubber product in a hot car, as heat accelerates the deterioration of rubber (in which case a backup mask stored in the same location might not be any more reliable)? Also, if you usually wear the strap over a hat, seems like the degree of stretching that might be needed to put that off and on might be a little more than the mask was intended for. Last but not least, I noted your upper strap was twisted. I don't know how much of a difference that makes, but I always bring mine flat after putting the mask on, starting at the connection points, and just running the strap through my fingers on both sides until they meet in the back. This also ensures the tension is evenly distributed along the strap.
"Is it quite fair to call it failure "without warning" "
I would say yes, because the 3M 9210+ straps don't do this, they don't just break spontaneously while you are wearing the mask the way Aura straps can and do. The braided 9210+ straps are fault tolerant. Catastrophic failure of the Aura headbands is a known issue, so much so one doctor wears a cup-style N95 over his auras because he can't afford a strap failure while doing a procedure.
And, yes, I do wear the straps over a flat cap, but some people have bigger heads than I do, so that minor increase of my wearing a hat (a measured difference of 1/2" extra extension, from 18" to 18.5" wearing the hat I normally wear) is well with in the expected operating range the straps are meant for.
For me it is reassuring that leaving the mask inside a warm car for three weeks did not affect the filtration. Sometimes it gets warmer in Europe than the 25 degrees Celcius that many masks give as the range to store the mask in (and most of us have no air conditioning). This means that the mask material can withstand some weeks of higher temperatures. Masks often have an expiry date. How safe is it to use a mask that is, say, 1 year beyond that date?
Can you measure the fit factor with both straps behind the neck(at the bottom)?That's how i go to do my haircuts nowadays.
I did a fit test on a friend who does exactly that.
With the straps used normally she got a fit factor of 227, that is it was 227 times cleaner inside the mask than outside the mask. (A leak of .4%)
With both straps behind her head she got a fit factor of 59 (a leak of 1.7%).
So, the mask worn with the headbands behind the neck was about 1/4 as protective as when the headbands were worn normally.
The mask fits her well, so even with both straps behind her neck she still did get much better protection than most people get from their masks. I can't guarantee that you will get the same results since fit is very individual.
I have also cut the headbands in half and tied them into ear loops for the same purpose, for haircuts - they were a little tight, but that combination fit tested very well on me. About the same as with headbands in my case. But the tension matters a lot as we saw from the cut strap test. So you do need good tension and in the right direction. And, again, I can't guarantee you'll get the same fit and results because it is very individual.
@@gerardhughes Interesting! Thank you for the reply.Considering the stamps my Aura leaves all over my face,probably i would get an equal or better fit factor.
When you say 3 weeks of use, is that like an hour each day or 8 hour work day? Huge drop in just three weeks.
The mask was used intermittently, maybe an hour most days, up to 4 hours. I don't do shift work in a mask, so I don't have used masks that are good examples to compare to that.
It's possible the lower score I got was just an anomaly. Sometimes that tests are a little bit different from one another because mask fit isn't always perfect every time you put it on.
Another possibility is that the straps get stretched out on the 3M Aura 9205+ model specifically each time you put the mask on and take it off off rather than from the length of time you wear the mask. I suspect the filtration media is just fine, I think it was strap tension that caused the lower score. But I'll need more tests to establish whether that's the case.
@@gerardhughes I do wear these ones and I think it's a strap issue as sometimes mine break even within a week :( I'm also wondering over time would the filtration itself lose effectiveness? I change mine every few weeks....that's if the strap hasnt gone by then!
@@asmrfoodieuk7965 I suspect that 3M has all sorts of data on this, but doesn't necessarily share it.
A 3M rep Aaron Collins interviewed says you can keep wearing N95s until they are soiled, damaged or can't keep a good seal.
ua-cam.com/video/6tk9PNOHWng/v-deo.html
I think the filtration media should hold up well, which is something Aaron Collins has tested with KF94s used over time. With the Aura 9205+ with the blue bands, the straps are the biggest weak point for me.
I plan on doing some experiments to try to find out how much wearing the mask stretches them out, vs how much putting the mask on and off does, and how much being in the car does.
But, my sample size will be small, and my testing methods will be very much middle school science experiment, so the results will not be perfectly reliable.
@@gerardhughes for me it's taken it on and off constantly as I take my work breaks outside and there several times throughout the day, it weakens them so much. What's the relation with the car making them weak? Look forward to the mini experiment 👍
@@asmrfoodieuk7965
Leaving them in my car in summer exposes the straps to heat, which may weaken them.
Unfortunately, I do not have a low temperature oven so I'll have to test whether heat affects the straps by leaving a mask in the car and comparing to one that was kept at controlled temps.