Enforcement Rules of Labor Union Act Article 28

When union members or member representatives request to audit the financial situations of the labor union, they shall file in writing.When proceeding to audit the financial situations of the labor union in accordance with the preceding paragraph they shall be accompanied by a supervisor. If the labor union has a board of supervisors, the supervisor shall be designated by the board in accordance with Paragraph 3 to Article 18 of the Act.
中文原文 工會法施行細則第28條
會員或會員代表依本法第二十九條規定查核工會之財產狀況,其連署應以書面為之。
依前項規定,會同監事查核工會之財產狀況,於設有監事會者,依本法第十八條第三項規定,應由監事會指派監事會同查核。

English translation for reference only; the Chinese text prevails. Not legal advice.