Electronic – What do these two icons mean

lead-freepcbpcb-designrohssafety

image

Left one – "no plumbum/lead"

Right one – "triangular invert color no picking by hand"

(found on BeagleBone Green)

Best Answer

The "no Pb" means that only lead-free solder was used. For most of the 20th Century, the most common type of solder was made from lead and tin. Lead may have other uses in electronics, but I can't think of any offhand. Lead was leaking from landfills containing discarded electronic products. Lead was banned or limited. The device in the photo conforms to the new standards.

The "no hand" symbol tells people to not finger with the board, almost certainly due to digital chips or especially sensitive transistors such as MOSFETS. A little static electricity could damage those components. A lot of static electricity - well, that's just plain bad sensitive components or not.