Powered Respirators Vs Dust Masks

[deema]

The problem with unpowered masks is getting a perfect seal, and as the filter starts to clog up the negative pressue that breathing creates causes dust to enter around the edge of the mask due to the pressure difference. If you the read the 3M7500 instructions it actually says that it's time to change the filter when you notice your getting a bypass around the mask.

The powered masks have far less issues with bypass as they have positive pressure. The Trend Airshield must be checked regularly for the pressure with the included tester. If the filters get too blocked the positive pressure is reduced to the point where you get bypass and breath unfiltered air.

The other thing to consider is where you buy cheap disposable masks, if it says it's P3 and is from an unknown retailer and its from China, chances are it isnt even P1. There may be standards, but there is no one actively policing them. The prospect of suing someone in China for a faulty mask when you have lung problems is a none starter. So, a leading retailer may be more expensive buy but you do have a high degree of assurance that they will have verified that it actually does what it claims to do.

So, IMO in summary the positive air pressure masks have a lower tendency to create bypass if tested properly. Although P2, which by the way is above what is recommended for MDF (P1).

Personally use a Trebd Airshield for most woodworking and for painting / thinners etc use a 3M7500 with both a p3 filter and an organic filter. Of the two the Trend is a long way more comfortable and wearable all day long compared to the 3M, which if fitted correctly should leave a faint impression all around your face when you remove it.

 

[skipdiver]

Think I'm going to get a power cap and hope it does the trick as it's 200 quid wasted otherwise.

 

[n0legs]

n0legs what extra is involved when getting air from a compressor clean enough to breathe. I picked up a 3M hood and regulator recently.

Hi Wallace,
I modeled mine on my BIL's at his workshop (body shop). His is obviously bigger and better (expensive), but mine is still effective.
I asked the guys who service his compressors for some advice and basically the more filters the better. Getting the water out is hard if you don't have a dryer, but it is doable.
My air fed mask is an older DeVilbiss set up with a belt mounted filter pack. I believe this filter does the really hard work and needs changing every couple of months if used a lot, mine gets changed at most twice a year.
Filtration starts with a Clarke filter, I've had this years. It's a really simple thing with a water drain on the bottom.
The filters I bought to use the air fed are these:-
http://www.sturdyfluidpower.co.uk/Produ ... 110004000f
There's two of these always connected and are inline with each other after the clarke. The second one has a push fit/quick release fitted. I just plug tools in when in use.
To use the mask I connect one of these:-
http://www.sturdyfluidpower.co.uk/Produ ... 110004000e
It's got a male push fit one side and a quick release the other.
I have a rubber hose for the mask and it only gets used with the mask, I cap the fittings when it's not being used. I don't know the spec of it, it came from the people where the filters came from upon request for something suitable. It gets cleaned every now and then using the same method as the BIL.
He has an inline oiler that has never been used for oil. He fills it with a sanitiser, Dettol I think (don't quote me on that) I'm sure it comes from a first aid place. Then plugs the airline in, letting the oiler feed the contents down the hose. The hose is then just left to blow for ages to dry it out. I do mine down there, the compressors are much much bigger than I have at home.

What I will say is wearing the air fed kit, whilst you feel super safe (you really can't taste or smell anything other than air), it is a pain. The hose drags along behind you and depending how vigorous the work you're doing it can really get in the way. I wore it when we did the paving last summer when doing all the cuts with a disc cutter. Yes it was nice and safe not breathing in the dust, but christ it got on my ****. Walking the same way each time to my pile of uncut slabs, so as not to get caught up, then back to my cutting station, then over to put the cut piece in another pile. Wow really tedious, and getting it snagged -- right pain. But still I didn't breathe in any dust.
Then there's from the noise from the compressors. that really wears thin.
It's nice to have but there are limits. I don't know how the painter at the BIL's does it for 6-8 hours a day, it would drive me bonkers.
Makes me feel like a goldfish :lol:

 

[MattRoberts]

Deema, did you know you can get a charcoal filter for the trend for when you use chemicals?

 

[PAC1]

Think I'm going to get a power cap and hope it does the trick as it's 200 quid wasted otherwise.

If you spend all day all week in the shop then you really should be collecting all the dust at source and wear a mask only for machines with leakage or where 99.9% collection is impossible. You really cannot believe the difference in the environment including air quality when you achieve this.

 

[deema]

Deema, did you know you can get a charcoal filter for the trend for when you use chemicals?

I didn't, that's really helpful thanks. I will look out for the filters because apart from paint spraying that would be ideal.

 

[lurker]

Deema, did you know you can get a charcoal filter for the trend for when you use chemicals?

It's not quite that simple as a quick look at the range of different filters wil demonstrate

 

[wallace]

Thanks for all the info, I was thinking of using air fed when I'm turning so I didn't have to drag air lines around. Also for when I'm doing restoration work on machines, I wanna be as protected as possible because I'm probably dealing with lead based stuff. Another avenue to go down could be pumping air as apposed to compressing air. A few years ago I played with a little 12v fan that was army surplus and came off a cold war radar system. It took an air feed from outside and pumped it down some new 1" hose to a mask. It worked fantastic but the hum off the fan was horrible.
I might try one of the new powered respirators since they seem to be P3 now

 

[skipdiver]

Think I'm going to get a power cap and hope it does the trick as it's 200 quid wasted otherwise.

If you spend all day all week in the shop then you really should be collecting all the dust at source and wear a mask only for machines with leakage or where 99.9% collection is impossible. You really cannot believe the difference in the environment including air quality when you achieve this.

Yes, i am aware of that and am upgrading my dust extraction as well. Ordered an air filter unit today and will endeavour to keep improving all the areas i can. The airflow mask is just another facet.

 

[skipdiver]

Now have the AC unit fitted and used the Powercap for the first time today. Was routering for hours with my table hooked up to extraction but there is always some dust that escapes. The AC and Powercap kept it all at bay and the shop had no dust hanging in the air when i had finished. It also kept my napper cool on a hot day. £360 well spent.

 

[skipdiver]

Well, it was good while it lasted. Put it on charge for 16 hours ala instructions and it died after 10 mins use this morning. Seems the battery is not charging and it's going back to Axminster tomorrow. Very disappointing and am not sure whether to get another or have a refund and get a Trend one.

 

[CHJ]

Well, it was good while it lasted. Put it on charge for 16 hours ala instructions and it died after 10 mins use this morning. Seems the battery is not charging and it's going back to Axminster tomorrow. Very disappointing and am not sure whether to get another or have a refund and get a Trend one.

Did you actually confirm that the current was flowing from the charger to the battery?

I f the battery pack is charged in situ I always switch the device on and then the charger, the immediate increases in fan speed confirms that the charger is supplying power to the unit.

 

[skipdiver]

Tried everything but it wouldn't charge, so it's going back.