4 All removable internals shall be checked by suitable methods to ensure their insertability and removability through the manhole.
所有可拆除内件均需使用适当的方法进行检查以确保其通孔的可嵌入及可拆除。
4 All removable internals shall be checked by suitable methods to ensure their insertability and removability through the manhole.
所有可拆除内件均需使用适当的方法进行检查以确保其通孔的可嵌入及可拆除。