The following article is a letter sent to WorkCover News by LAS (NSW) in response to an enquiry received by LAS (NSW) from a female radiator repairer. Comments by Prof. Chris Winder in italics.

Despite being recommended in "WorkCover News" [No. 32, June - August 1997], our research suggests that not only is lead-free solder rarely used in radiator repairs, but it is also much more expensive than normal leaded solder and its suitability to radiator repairs is open to question.

The normal solder used for radiator repairs contains 60% lead and obviously from the case reported in WorkCover News the fumes affect those working with it, potentially leading to a variety of health problems for workers.

We rang Bob Littley [Senior Inspector, Chemical, Legislation and Investigation Section] of WorkCover NSW, who said "I don’t know anyone who uses it [lead-free solder]". He said the solder "has not been tried or tested in NSW" and that the feeling in the radiator repair industry is that they don’t know what the strength and penetration is and they "can’t afford to use it in case it doesn’t work and comes back and has to be done again for nothing". He also said modern radiators are plastic [or ceramic] and that the radiator soldering industry is a dying industry. As Professor Chris Winder points out - "Elimination of the need for leaded solder is the right approach - you don't need solder if you design right!"

Bob said there were currently [June 1997] two suppliers of lead-free solder: "Multicore Solders Australia" and "Consolidated Alloys".

We rang Multicore, who said that most radiator repairers go for a cheaper alloy than lead-free solder. They said that the lead-free solder costs $16/kg, whereas normal solder costs $8/kg. Unlike leaded solder, the lead-free solder also has no "sticky stage" - in-between solid and liquid - where it is more workable. A lot of the success of the solder depends on the flux you use [which helps the solder stick] - Flux 305 and Flux 366 are popular for electronics purposes, but because radiators are so dirty it would be "trial and error".

A female radiator repairer rang Consolidated Alloys and was told there is no lead-free solder for the radiator industry. Consolidated Alloys supply a product called "Aquasafe", which they recommend for plumbing, but it costs $31.15/kg and is not recommended for radiator repair - they had not researched radiator repair solders. Aquasafe apparently requires temperatures 20 - 30 degrees higher than normal solder in order to melt, and even if you had a lead-free solder, you could still get lead fumes from the lead which is already on the radiator. They said using lead-free solder on radiators would be trial and error - some of the failures you would get twelve months down the track.

The "Welding Technology Inst. of Australia" said the short answer to the problem was to use specific hood ventilation to draw away the fumes.

See: Working with lead – Radiator repair WorkSafe Victoria, 16 July 2009.

Quotable Quotes

"I had a tradesman come to quote on a job and when I questioned if the paint contained lead the tradesman pulled some paint off the wall - ate it - and declared it was safe" [heard at a workshop run by Michelle Calvert for LAS NSW]