Has ‘Paxolin’ ever contained asbestos?

[Phil G4SPZ]

The reason for this question is that a survey by some asbestos consultants at the Museum, where I work as a volunteer, has resulted in big asbestos warning labels being stuck on some vintage radios and record players, mentioning Paxolin specifically.

I am aware of the possible presence of asbestos fibres in Bakelite, or in panel form near mains droppers, and the appropriate precautions are well known. But in Paxolin or SRBP? I can find no references to it ever having incorporated asbestos.

[Maarten]

I don't know paxolin specifically, but since it's a bonded fibrous material it would be quite easy to uses asbestos instead of or in addition to paper. Being bonded, this would not be a problem, unless disturbed. Also, I would guess the likelihood of it including asbestos can be estimated by eye.

[paulsherwin]

This seems extremely unlikely. My guess is there's a paper somewhere saying that some circuit boards 'may' contain asbestos, and this has been picked up by the 'trainers' of the consultants. We all know that modern H&S culture is extremely risk averse, and people doing any sort of analysis are primarily interested in covering their rear ends,

[McMurdo]

Just had a quick google about, as we used loads of paxolin-type sheets when I was an apprentice and used to cut it with a hacksaw, phenol-like smell and dust everywhere.

Paxolin was a trade name of a resin-bonded paper made by Miconite (aka M&I) , last registered in 1948 and expired and not renewed by 1997 whenupon it became a generic name for any resin-bonded paper, woven cotton or glass fibre laminate. M&I are still trading in Manchester after having passed through the ownership of Metrovick, AEI and GEC. (source: .gov and M&I websites)

Certain grades of the similar Tufnol could be supplied as an asbestos bonded laminate but I believe these were super high-performance materials for high speed bearings and friction surfaces. (source: lawyers specialising in asbestos claims).

Sounds like an over-reaction to me. I shan't be putting any yellow tape around my 30's radio collection.

One of my industrial clients runs a textile mill dating from the mid 1800's. They have fire doors in between levels which were installed in the 1930's. They use asbestos sheets over wooden frames. They are so thickly painted after 90-odd years of redecoration that I'm sure they're half an inch thicker than when they were installed. A recent risk-assessment of the working environment has seen prohibition notices slapped over the doors, and they've got to come out. Men in white suits will be called.

[chriswood1900]

I have never heard of Paxolin containing Asbestos it is made up from paper with Phenolic resin under pressure, the similar product Tufnol is resin bonded cotton.
Neither is on the HSE list of product’s likely to contain asbestos.

[Radio Wrangler]

The name SRBP Synthetic Resin Bonded Paper was used as the generic to avoid saying the registered trademark "Paxolin"

The other material on the go was "Tufnol" being a synthetic resin bonded cloth. Much tougher, fibrous and layers of woven fabric could be seen in the material. It was also amenable to being turned, milled, drilled and tapped. I don't believe any asbestos was added.

Adding Asbestos to SRBP sounds odd. The primary selling point of asbestos was its resistance to heat. The resin in SRBP would give in long before asbestos would be needed. These resins being thermoset types, of course.

David

[stevehertz]

During my twenty years at Thorn Automation I came into contact with paxolin on a daily basis used as insulation and packing between electronic subassemblies. I also acquired pieces to use in foreigners and would saw and file them. At no time did I ever see or sense any kind of fibres in cut sections or filed areas. That's just my anecdotal take on it.

[Ed_Dinning]

Perhaps you should ask the H&S people to justify their asbestos call on paxolin.
The call "it might/ to be on the safe side" only seems to justify their large fee for disposal.
If any good these people should be able to document their reasons

Ed

[turretslug]

I'm as wary and concerned about the presence of asbestos in various situations as anyone- but my cynical side wonders if, as asbestos-containing materials are progressively eliminated from day-to-day life, we're going to see less-than-honest vested interests falsely tarring more and more materials as suspect. People are understandably fearful of this insidious substance, and it's difficult to prove that a proprietary material never included asbestos from any manufacturer.

A variation on the shysters knocking on the timid old widow's door, telling her that her roof's in terrible condition with a sucking of teeth, followed by, "Tell you what, we can sort it for cash".....

[M0FYA Andy]

I have a catalogue booklet from Tufnol listing all their products (I don't have it in front of me but I think it dates from the 60s). They certainly explicitly included a variant containing asbestos, but I think this would only turn up in very specific applications.

Andy

[Phil G4SPZ]

I’m indebted to all contributors for this comprehensive series of responses. I concur with the view that the surveyors are being ultra-cautious. Bear in mind, too, that they never actually dismantled the equipment to look inside. To do so would expose the surveyor, presumably.

I propose to invite these experts to provide documentary evidence of the specific risks posed by Paxolin.

Thank you all.

[Craig Sawyers]

Made and sold by Presspahn https://secure.presspahn.com/Cart/150-srbp-paxolin-p1

I buy sheet material from them from time to time in various thicknesses. No asbestos in the stuff.

Craig

[Radio Wrangler]

We're into territory where the deciding factor is "Might" augmented by "We can't check to find out for fear of exposure"

It's a bit like the accusation of witchcraft.

If applied similarly, all waste becomes hazardous waste. There is no discrimination between 'really does' and 'really doesn't'

David

[stuarth]

After any obvious fibrous heat shielding materials (which the surveyors would not know about if they didn’t look inside the set), I think the most worrying thing inside an old set would be the dust collected over the years. Without knowing where the set was used, who knows what’s in that dust. I wouldn’t worry about the Paxolin. How did the surveyors know there was Paxolin in them anyway?

Stuart

[Trigon.]

From the Tufnol website:-

https://tufnol.com/glass-fabric-lami...l-grade-6g-92/

What is Tufnol Grade 6G/92 used for?

Tufnol polyimide glass laminate is widely used throughout industry, particularly in the aircraft industry, as electrical insulation and in industrial machinery where high temperatures are required. Applications in general engineering range from heat barriers on plastic injection moulding machines, to support assemblies on diesel engine exhaust systems.

It is also used for certain high temperature applications where asbestos based materials were previously used. Typical examples are:

Sealing rings in high temperature chemical plant
Components on equipment for use in microwave ovens
Terminal plates for high temperature strain gauges
Aircraft components, such as high temperature insulation on jet engines
Electrical insulation fixtures for high temperature testing of solid state devices
Scraper blades in high temperature processing

It doesn't actually say the previous 'asbestos based materials' were a type of Tufnol though...

Cheers

[Craig Sawyers]

I bought a Tektronix transient digitizer some years ago from the US when USPS used to do really slow shipping by ship that was cheap (they no longer offer that option).

From where the seller lived it was a fair guess that the unit come from Los Alamos. It was fairly dusty and gritty inside.

Who can say what that dust and grit was.

But like David said, might or might not. That way lies madness.

Craig

[David Simpson]

As a young RAF trainee, back in the early '60's, paxolin-wise, use of & construction projects were a major part of workshop training. Ten years later, I was back as an electronics instructor - heaps more paxolin work !
There was never any mention of asbestos at all. So no worries chaps.
The only worry, looking back, was the use of so much CTC to clean off flux residue on completed paxolin based projects. Then, to make things jolly presentable for an instructor's examination & marking, a wee dab of Hellerine was used polish the paxolin's surface.

Regards, David

[Nickthedentist]

I cannot understand why it is even relevant to Phil's museum whether or not Paxolin contains asbestos.

Unless he's planning to drill or cut it, fibres cannot escape.

Droppers and heatshields are a different matter of course, and caution (along with a "common sense" risk assessment) would be advised.

[high_vacuum_house]

Good morning,
I would rather like to know what "expertise and experience" the asbestos consultants have in regard to old equipment. I cannot see any issue with Paxolin as any fibres would be encased in resin and cannot be released into the atmosphere. Were they doing a survey for a particular reason, i.e. for H+S audits.

The material I would mostly be concerned about in valve equipment is the getter and cathode materials in valves which I think can be a bit fruity if exposed in large enough quantities (though we usually try and keep them inside the glass!!)

I have had a fire safety "expert consultant" visit me at one of our power generation sites and wanted to remove all powder fire extinguishers and have only CO2 instead. (because they make a mess was the reason!) This is on a site where oil fires would have been high and CO2 extinguishers would not have smothered any oil burning fire!
Also wanted to fit an extinguisher on a bracket in a place that would partially block a fire door! I ignored all of his advise and recommendations!!

Christopher Capener

[Nickthedentist]

Originally Posted by McMurdo

One of my industrial clients runs a textile mill dating from the mid 1800's. They have fire doors in between levels which were installed in the 1930's. They use asbestos sheets over wooden frames. They are so thickly painted after 90-odd years of redecoration that I'm sure they're half an inch thicker than when they were installed. A recent risk-assessment of the working environment has seen prohibition notices slapped over the doors, and they've got to come out. Men in white suits will be called.

Our local, nationally-renowned hospital was built in the late 1970s.

On the ward my dad was recently in, there were substantial fire doors between the lifts/stairs, and the wards. They looked like they had painted asbestos panels, and sure enough, there was a little sticker on them to say that this had been proven. But as it was all sealed, they were declared safe for purpose, but was prohibited to drill into them to attach hooks etc. Common sense indeed.