Posted By davepennington2009
I am putting together a risk assessment for stud welding and am a little uncertain whether or not this activity would require a hot work permit ?, if it does then this would change the whole scope of the work to be carried out, sheeted scaffold ect. Anybody who has been involved with stud welding will probably have some answers, please let me know.

Posted By Bob Youel
it is hot work but common sense needs to come into play so create a proper RA + method of work thereafter a PTW will be found as needed/not needed

I would treat it as needing a PTW noting that a PTW can be a simple document/procedure

Posted By AHS
IMHO if they have a fire extinguisher and there are no flammable materials/explosive atmospheres present or anything else to complicate matters probably not - too much paperwork I think ridicules safety.

Posted By John Richards
There are two different types of stud weld[er].
Capacitor discharge: used to weld small diameter studs to thin parent metal. The stud to be welded onto the metal has a small "tip" that is placed upon the metal. The capacitor is then discharged through the stud melting the tip....a sping then forces the stud down pushing the molten tip into the pool of molten metal on the workpiece and hence the sweld is completed.

And Arc-Stud weld where the stud has a ceramic shield on the "welded" end. The stud is lifted from the metal and the arc initiated, then the stud is plunged down onto the work and the weld is done.

In both cases molten metal is present. Even if the job is done right there will be sparks flying around, if done wrongly there will be lots of molten metal as well !

Posted By Coshh Assessor
I agree with Crim; ensuring that an extinguisher is available, combustibles are removed, etc, is the whole point of a hot work permit!

Posted By Barrie (Badger) Etter
Dave
I find I have to disagree with MCK.
Just to clarify, is the process similar to spot welding?
If as I believe is so, then NO to your question (as long ago assoc'd with such) you'd be filling out a hot work permit every working day of the year!
A simple welders screen between each welder to arrest the flying sparks is enough and time to clean (sweep up) the area to remove any last 'living' sparks at days end. Hope this helps.

Contact me direct should you wish for further with digi photo of area.

Badger

Posted By Merv Newman
In agreement with CW. If welding is only done in a reserved place, which has been inspected and declared "OK for hot work" then no additional individual or daily HW permit would be required.

Just like in a dedicated welding shop or booth.

Merv

Posted By MCK
"if it does then this would change the whole scope of the work to be carried out, sheeted scaffold ect."

This does not sound like a welding booth or controlled environment to me. If it was i would agree that no permit would be required.

Again we do not have the whole story??

Posted By Pete Longworth
Dave

My first question would be, is this going to be a regular activity ie some form of production operation or is it only going to be done occasionally. If it is a regular production activity it makes no sense to issue a hot work permit every time it is used. If the process is properly assessed and the work area set up to take into account the evolution of sparks etc.with the requisite controls. If this is supported with a suitable fire risk assessment then I don't believe that a hot work permit would add any value to what you already have.

If the stud welder is used occasionally then a hot work permit may be useful, but a permit by itself won't protect you from fire. All it will do, if used correctly, will be to force you to implement the relevant controls, before the job starts, and inspect the area for signs of fire at an agreed time interval after the job ends.

At the end of the day hot work permits are not mandatory requirements. It is up to you what you do to control fire, as long as what you do is suitable and sufficient to your needs.

Posted By Andy Brazier
You cannot possibly say that a hot work permit is "definitely not required." It will depend entirely on where the work is taking place. If on an oil refinery or gas terminal I would suggest that a permit will definitely be required.

It bothers me that people are suggesting that if a hot work permit is required that different precautions will be required. This suggests to me that the permit system is either too rigid or is being misapplied. The problem is that people start to look for reasons why a permit is not required and can end up bending the rules too far so that risk controls are missed.

A permit to work system should not change the controls required for job. In fact, whilst it is a useful way of assessing a job and communicating controls, one of its key roles is to help coordinate work and avoid incompatible jobs taking place at the same time.

Posted By Barrie (Badger) Etter
The reason for saying HWP is not required:
1. The arc generated lasts for less than 1/2 a second
2. The stud being attached is normally around 5 to 8 mm
3. Heat disapation into base metal ie, that which the stud is attached to is nominally 5x's the stud dia. so at worst there's only localised material distortion
4. Yes there are sparks but if the system is set up properly they should be very minimal
5. What has not been indicated is if this is a manual application or automated. If automated then the system will / should be fully enclosed.

The rest I have already stated earlier speaking from past experience.

Badger

Posted By Paul

Hot works permit is required, as from information received to this thread, suggests that weld sparks will be generated.

I agree with posters, in that the work locations, will denote the risk assessment.

One must remember we must do all the is Reasonably practicable to prevent risks from hazards at workplaces.