Soldering -- Tips and Best Practices

Updated July 31, 2013

Prevent skin burns and fires

Never hand someone a soldering iron, even if you think it isn't hot there is no way to tell until it’s too late. A soldering iron burns skin faster than a frying pan, stove top or oven. They usually operate around 500-700°F. Place the soldering iron back in the metal holder and let the other person pick it up.

While soldering, be sure to keep at least 2-3 inches of length between the tip of the solder touching the heat and where you are holding it. This helps prevent accidental burns.

Be aware of your surroundings. Create a soldering station free of combustible materials and an area where others recognize the hazardous work being performed.

When putting away the soldering iron, always turn off, unplug and LET IT COOL before wrapping up the cables and stowing it away. A fire started when a researcher put a Soldering iron back into the drawer and left the lab in a hurry.  The custodian noticed smoke coming from the drawer when they started cleaning the lab.

In general, hold the soldering iron like you would a pencil, keeping the wire running to the iron on the outside of your working area. This decreases the likelihood of you melting the power cable accidentally.

Prevent exposure to fumes

Always solder in a well-ventilated area. If possible, use a soldering hood to draw the fumes away from you. Over exposure to these fumes can be toxic.

Wear safety glasses while soldering. Fumes and hot solder/ flux can irritate the eyes.

Lead-based solder works better than lead-less solder. Unfortunately, lead is also toxic, so if you are using lead-based solder, WASH YOUR HANDS afterwards.

Age limit 

High School students, who are learning about soldering, should be closely supervised to reduce the risk of injury.  Middle School students should only observe their mentors solder, instead of doing it themselves.