What must portable power-driven circular saws have for safety?

Portable power-driven circular saws are designed with safety in mind, and having both an upper guard and a lower guard is essential for preventing accidents and injuries. The upper guard covers the top of the blade, protecting the user from potential contact when handling the saw. The lower guard serves to shield the bottom part of the blade, providing additional safety when the saw is in use or when it is being set down.

The presence of both guards ensures that the blade is covered except when it is in contact with the material being cut, reducing the likelihood of inadvertent injury. This dual-guard system is a crucial feature for promoting safe operation and is typically mandated by safety standards and regulations governing the use of such power tools.