What is the purpose of a welding helmet in the mechanics lab?

The primary purpose of a welding helmet in the mechanics lab is to protect the welder's eyes and face from the intense light, heat, and potential sparks generated during the welding process. It is essential to safeguard against harmful radiation, such as ultraviolet (UV) and infrared (IR) rays, which can cause severe eye damage or burns.

While wearing safety glasses underneath may offer extra protection against flying debris, it is not the main function of the welding helmet. The helmet includes a tinted lens to reduce glare and improve visibility while ensuring the welder's safety. Thus, the correct answer focuses on the critical protective features of the helmet, emphasizing its role in ensuring safe welding practices.