Powered Respirators

[Democritus]

Blister,

Do you have the Sundstrom 570SR with the Sundstrom 500 respirator?
D.

 

[Blister]

Blister,

Do you have the Sundstrom 570SR with the Sundstrom 500 respirator?
D.

Yes

 

[Lefley]

I started work back in 79 at Thames Marine who built GRP yachts & industrial mouldings. The guys who trimmed the mouldings were issued with the then new Racal Airstream helmet powered respirator, I believe they were designed for the mining & other hazardous industries. One of them showed me this bit of kit & told me what a difference it made.
In 84 I set up on my own & bought an Airstream powered respirator. At that time it cost £200, I worked in most of the local boatyards & i think i was the only bloke who owned one. At times doing a lot of GRP repairs & wood machining & sanding I virtually lived in it.
It lasted 20 years then i bought another one. 15 years later that one was getting worn out, Racal was brought out by 3M who continued making them, i bought three of them secondhand stripped & cleaned them & bought a pile of parts to keep them going. Most of the parts are still available except for motors which i cant find.
One of those GRP trimmers (who refused to wear one) died of silicosis, Several other chippies i know died of Copd & several more are now having problems.
You cant buy new lungs so investing in a good respirator makes sense!
3M, Sundstrom & Martindale are three manufacturers that spring to mind.
A quick google finds the following, Air Fed Mask | Powered Air Respirators | Air Fed Respirator Mask ,
Make sure you are sitting down when you look at the prices!

Yes but have you seen the price of a new set of lungs! Let alone the price of anti rejection medication if you even qualify!,,,,,,!,,,,!

 

[Paul Hannaby]

The power cap and Trend face shields will offer good protection from impact to the face and head when regular woodturning.

The trend respirator offers no protection to the head and has no rating. The power cap has a bump cap rating. I don't claim to be an expert on that but it's a different standard to hard hats and sounds like it's a lesser rating.

There was a sad news story posted on here a few weeks back of a 30yr old who recently was hit and killed by a workpiece flying off his lathe.

I hadn't fully realised that different safety glasses/shields offer different impact protection and shouldn't be used with some high speed tools. My full face shield is rated for high speed impacts as are my bolle glasses but my standard type dewalt glasses are not.

What face shield do you use that has a high speed rating and which rating does it have?

 

[Agent_zed]

What face shield do you use that has a high speed rating and which rating does it have?

I'm not using anything fancy just the cheap one from toolstation but it is B rated which is rated for 120m/s impacts, but even the more expensive ones seem to be B rated so I figure it should be ok. More expensive ones will most likely have perhaps a better optical rating or have a better shape etc. A lot of my safety specs are only F rated which is 45m/s.

It can get a bit confusing with all the various letters and numbers. but these 2 sites for example have more info.

https://www.safetyspecs.co.uk/british-standards
https://www.seton.co.uk/how-to-choose-safety-glasses

 

[Democritus]

Yes but have you seen the price of a new set of lungs! Let alone the price of anti rejection medication if you even qualify!,,,,,,!,,,,!

I note that you are in Canada, so lung transplant and associated medication would cost a fortune. Here in the UK we have the NHS....
Not that is any recommendation to not use dust protection!!!

 

[Inspector]

I note that you are in Canada, so lung transplant and associated medication would cost a fortune. Here in the UK we have the NHS....protection!!!

If you qualify, transplants are paid for here too if you live long enough to get one, although some medications would be on your dime. Each province is a little different as each runs their own show.

Pete

 

[Democritus]

Thanks, Pete.
My comment was given ‘tongue in cheek’. Nobody should act in such a way that, potentially, they put themselves in need of expensive medical treatment, no matter who picks up the bill.

 

[Rewound]

I'm struggling to believe the prices of these things, seems like a total rip off to me. Just look at the prices of some of the spares. The Powercap for instance, 4400mah battery - £108 I bought a 10,000 mah battery a couple of years ago, gets used all the time £16
And then look at the price of some of the more upmarket ones with belt mounted filtration units - £1000 - just stupid made up prices.

I might just make my own, can soon knock to gether a belt mounted air filter unit, connect via a flexible pipe to some sort of face shield/ helmet, even a motor bike helmet!

Just looking at the powercap (the only one I could afoard) . It claims 8 hour run time for a 4.4ah battery Im thinking this is suggesting a fan around 2.75w
that is just a computer case fan!
I could soon mount two of them together and double the air flow of the powercap still only running at 5.5w (that is just over 1 amp) bog standard powerbank can easily do 2 amps.
Make a case and fit a couple of p3 filters - thats half the job done.

 

[Paul Hannaby]

It seems that anything under the PPE category has over inflated prices. Part of that may be due to the legacy of Covid, I know the disposable P3 masks I used to buy are now 3-4 times what they cost pre-covid so I have switched to a more economical brand. The high end belt pack respirators have always been eye waveringly expensive but they also seem to be the only ones that offer TH3 rating. Perhaps worth the extra for another 3% of protection!

 

[Lefley]

I note that you are in Canada, so lung transplant and associated medication would cost a fortune. Here in the UK we have the NHS....
Not that is any recommendation to not use dust protection!!!

In Canada our medical is free! We do not even pay a monthly fee.

 

[Inspector]

Depends in which province you live in Lefley. When I lived in BC I paid a monthly fee (about a hundred a month) until our union negotiated for the company to pay it. If you were poor then the province covered it. When we moved here I found out there was no fee. So each province is different.

Now let’s get back to talking about powered respirators.

Pete

 

[Lefley]

Depends in which province you live in Lefley. When I lived in BC I paid a monthly fee (about a hundred a month) until our union negotiated for the company to pay it. If you were poor then the province covered it. When we moved here I found out there was no fee. So each province is different.

Now let’s get back to talking about powered respirators.

Pete

You don't pay a dime in bc. Employers pay everything. Changed years ago. And I just ordered a. 3m system.

 

[Keith 66]

20 years ago the Nicad battery pack on my Racal Airstream respirator failed, at that time the explosion proof battery pack was over £100, I sawed & split the case & found ordinary nicad cells inside, Got 4 new ones for £16.
More recently the battery failed again, A new 7.2v 4000mah NiMh battery pack that will fit inside the case is today about £17.
As for the cost of a top of range respirator, We know they are expensive but as yet there are no cheap far eastern knock offs about.
My Dad had a Trend airshield for a while & I tried it when he passed away. Flimsy & cheap with a tiny battery, I went back to the Airstream.

 

[Democritus]

It seems to me that powered respirators are as ridiculously expensive as everything else associated with wood turning.
D.

 

[Blister]

It seems to me that powered respirators are as ridiculously expensive as everything else associated with wood turning.
D.

Not compaired to a new pair of lungs " If you can find any "

 

[Sideways]

I'm struggling to believe the prices of these things, seems like a total rip off to me. Just look at the prices of some of the spares. The Powercap for instance, 4400mah battery - £108 I bought a 10,000 mah battery a couple of years ago, gets used all the time £16
And then look at the price of some of the more upmarket ones with belt mounted filtration units - £1000 - just stupid made up prices.

I might just make my own, can soon knock to gether a belt mounted air filter unit, connect via a flexible pipe to some sort of face shield/ helmet, even a motor bike helmet!

Just looking at the powercap (the only one I could afoard) . It claims 8 hour run time for a 4.4ah battery Im thinking this is suggesting a fan around 2.75w
that is just a computer case fan!
I could soon mount two of them together and double the air flow of the powercap still only running at 5.5w (that is just over 1 amp) bog standard powerbank can easily do 2 amps.
Make a case and fit a couple of p3 filters - thats half the job done.

You are absolutely right that this kit is £££.
I especially agree with your assessment of the batteries. I have a fancy Fluke portable oscilloscope and they charge nearly £300 for a replacement lithium battery pack for those. It;s only 4 cells for heaven's sake !

The comparison with computer fans isn't fair though. Those really are a commodity item built in huge numbers, but they are also designed to move highish volumes of air against very little resistance. Put one or even two against the resistance of a P3 filter, part clogged, possibly a corrugated flex hose etc and I expect that it won't do well at all. You need a differently shaped turbine that creates higher pressure. Probably a squirrel cage - like you find in some laptop fans perhaps but substantially bigger. They are not rocket science but someone has to design them, invest seriously in injection moulding tooling and manufacture in much lower volumes than computer fans.

Funnily, if more people were buying them, there would probably be more price competition. A few more COVIDs and maybe we'll see prices starting to come down !

 

[Rewound]

The comparison with computer fans isn't fair though. Those really are a commodity item built in huge numbers, but they are also designed to move highish volumes of air against very little resistance. Put one or even two against the resistance of a P3 filter, part clogged, possibly a corrugated flex hose etc and I expect that it won't do well at all. You need a differently shaped turbine that creates higher pressure. Probably a squirrel cage - like you find in some laptop fans perhaps but substantially bigger. They are not rocket science but someone has to design them, invest seriously in injection moulding tooling and manufacture in much lower volumes than computer fans.

Any idea what type of fan is needed ? a name, a type. I am seriously interest in building one of these things, I have a 3d printer etc that should come in handy.

I'm going to mock one up in the next few days with some 12v computer fans, P3 filtes , see if I can get some measurements of air flow rates. I will need to get some measurements from proper ones so that I have a goal to aim for, not sure how I will achieve that though.

 

[Democritus]

Not compaired to a new pair of lungs " If you can find any "

Hi Blister
As a retired medical professional I appreciate the need to protect the respiratory system as a whole ( i.e.not just the lungs) from harm, and the need to spend as much as you can afford to do so, bearing in mind the nature and intensity of your work. I think the problem is more acute for those who work in very dusty environments every day for hours on end than for those , like me, aged 77, who do about 3 or 4 hours a week in my workshop.
My point about expense, however, ( which I think is still valid )was that just about everything needed for wood turning, tools, chucks, etc. etc., is priced very high, certainly in the UK. Stuff may be cheaper elsewhere.
D

 

[Sideways]

Any idea what type of fan is needed ? a name, a type. I am seriously interest in building one of these things, I have a 3d printer etc that should come in handy.

I'm going to mock one up in the next few days with some 12v computer fans, P3 filtes , see if I can get some measurements of air flow rates. I will need to get some measurements from proper ones so that I have a goal to aim for, not sure how I will achieve that though.

Sundstrom's SR500 has a two speed fan that delivers 175 or 245 litres per minute.
The 3m versaflo tr300 and tr600 are specified at 2 or 3 speeds 185 / 205 / 225 lpm depending on the model.
Both have a feedback system that increases power to the fan and maintains flow as the filter becomes loaded. And an audible alarm when it can no longer maintain that airflow.

I don't know how the devices measure airflow, but to test performance, the sundstrom has a nylon bag with a simple "ball in a slightly larger tube" pressure gauge. The fan is connected to the bag, air blows in and leaks through the fabric of the bag, and the pressure read from the gauge.

It might be worth downloading the manuals for these three, but i'll look and if the fan is visible without dismantling, I'll put up a photo.

This is taken looking into the air outlet of the Sundstrom SR500.
If you are familar with impeller types, it's recognisable as a single stage centrifugal impeller, about 5" diameter.
These draw air into the centre and "throw" it outwards, the same way that a workshop hvlp dust extractor works but the impeller is more refined and of different proportions (bigger diameter, slimmer, closed on both sides and backward curving blades) which greatly increase the pressure that it develops.
Similar style of impellers are used in power showers, some air curtains, air blade cutters, and many industrial processes.