If you mean the regular contacts,you had better not wear, for it is very dangerous to wear contacts when we are in the high temperature,like during the barbecue .When serious enough, people may get blind. However, if you add one pair of professional electronic welding goggles, and use eye drops scientifically under the advice of the doctor, it is ok.
It is really dangerous and not safe to wear contacts while welding. There are several reasons for this. In the first place, welding itself is a dangerous job for the eyes. It may hurt our eyes easily. Then, the sparks are even more harmful. The sparks produced while welding may fly into our eyes and melt the contact lenses with their high temperature. Thus, our eyes may be hurt by the burn and heat. Therefore, you'd better not wear contacts while you're welding.
NO, that is absolutely dangerous. No matter you wear contacts or not, welding is a dangerous activity. Workers are always equipped well enough to protect themselves, especially their eyes. The temperature on the spot is very high, if the contacts are near it, the material of resin could be very fragile and give out some harmful substances, which are bad for the eyes. Moreover, the harmful gases and dust around the spot can be easily attached to the surface of contacts, which will also lead to denaturation of serin. So be certain not to wear contacts while welding and protect yourself well.