I was reading about tin alloys for electronics soldering and found it it has about 40% of lead in composition. Lead, everyone knows, it's very dangerous to breathe due to being a heavy metal. Also, I found some recommendations using the combination of an exhauster and a respirator when working with soldering. Is there any international regularization of which respirator type should I use? If not, which type do you recommend? Beyond this, is there any additional safety equipment recommended?
For economics reasons and for better soldering resistance, I've already discarded Pb free solder reflow.
Best Answer
The dangers of breathing soldering vapor has nothing to do with lead content of the solder. The vapor pressure of lead is so low at soldering temperatures that there just aren't that many lead molecules in the air.
The hazards of breathing soldering vapors is due to the flux getting vaporized, and sometimes parts of components emitting gasses when they get too hot. Lead solder is actually a little safer in that regard since soldering temperatures are lower. However, the biggest variable is the composition of the flux.
If you are worried about this, get something called a fume extractor. This is a little box with a fan and a filter. You place it right next to where you are soldering. It pulls the vapor from soldering away from you and thru its filter. By the time the vaporized stuff gets to the filter, it's no longer vaporized but a bunch of small particles. The filter removes these particles from the stream before exhausting it out the back.