本文件规定了便携式手持式链锯前护手及其开口的尺寸和间隙。这些尺寸和间隙确保了护手提供的必要安全性，护手既是操作员手和锯链之间的防护罩，也是手动操作链式制动器的执行器。 对于带缠绕手柄的链锯（见图1），本文件不适用于前手柄在顶部支架右侧（从后面看时）的部分。

This document specifies the dimensions and clearances for front hand-guards and their openings on portable hand-held chain-saws. These dimensions and clearances ensure the necessary safety provided by the hand-guard, which serves as both a shield between the operator's hand and the saw-chain and as an actuator for manually operated chain brakes. For chain-saws with wrap around handles (see Figure 1), this document is not applicable to the portion of the front handle to the right (when viewed from the rear) of the top brace.