Acceptance of PVC for fire resistance?

[wee brian]

there are some really high spec ones about - they have a plastic coating and look like UPVC but they are fire doors underneath.

[colin todd]

I was waiting for someone to tell them that Wee B. You can get  heaps of doors that seem like uPVC or fireglass but have an FR core.  The days of tapping fire doors or looking a surface finishes ended after the last World War.

[SamFIRT]

OK.........................

So I say again

How can you tell?

[kurnal]

You can tell a great deal by tapping a door Sam. I do it all the time. It will eliminate hollow doors straight away. Then if it appears to be of substantial construction you can tap it a bit harder. That can be especially useful when someone then opens it and you can then look for the label on the top edge or on the hinged edge.

Sorry to be a smartass but some folk round here want to try and help each other out whilst others just want to pick holes in everybody else' helpful suggestions but rarely seem willing to offer any practical solutions themselves. Foll de roll.

[AnthonyB]

you can then look for the label on the top edge or on the hinged edge.

If only every door had the label or the cores......most sadly do not! A pity it wasn't mandatory on all fire doors.

[SamFIRT]

whilst others just want to pick holes in everybody else' helpful suggestions but rarely seem willing to offer any practical solutions themselves

It would make me very sad to think that comment was directed at me Kurnal?  

If only every door had the label or the cores......most sadly do not! A pity it wasn't mandatory on all fire doors.

AnthonyB's post

Is actually my point. Along with my original post pointing out the manufacturers of uPVC are claiming it is in itself intrinsically fire resisting. It is not. And one of the qualities that it is claimed make the product self-extinguishing is the liberation of halogens by pyrolysis in the form (usually) of chlorine gas. Not particularly good for the lungs. Allied to this the pyrolysis liberated vapours are potentially extremely flammable.
 
I did an interesting experiment the other day igniting petrol on an apparent PVC door. It did not burn in the way I would have expected. The door was not marked or sold as fire resisting in any way. But it had an interesting core. Felt very solid to tapping as well.

 I did however, examine a PVC replacement front door to a flat that had charred to destruction and assisted in filling the dwelling with HSG which had subsequently ignited (the HSG not the door). The door was onto a common walkway that originally had been a balcony approach but had been modernised by the fitting of uPVC frame glazing to the balcony (enclosing it to a corridor) and replacement uPVC front doors to the flats. The newly formed corridor had filled with nasty HSG and the heat had started to char that PVC as well.

[kurnal]

Certainly not Sam. Why ever would you think that?

It was a muted snap in the direction of one Mr Todd, borne of frustration. A passing niggle that comes over me once in a while thats all.

I just wish he would give us a pull out of a hole once in a while rather than watching and laughing if we fall on our backsides. But then again we often have a lot of fun in the mud.

[SamFIRT]

 He he