As far as safety is concerned, this product meets all standards.

as 在这里是连词，表示"就...而言"或"在...方面"。 far 本义是"远的"，在这个短语中与as连用构成固定搭配。 as far as 是一个固定短语，表示"就...而言"或"在...范围内"。 is concerned 是动词concern的被动语态形式，concern意思是"涉及、关系到"。 as far as...is concerned 是一个完整的固定表达，意思是"就...而言"或"在...方面"。