Narcotics Hazard Prevention Act Article 33

To control and prevent the spread of narcotics, agencies of authority may, when necessary, request specific personnel, whom they supervise or monitor, to accept having a urine test. The request shall not be refused. Persons refusing to the test will be physically restrained for the sake of enforcement.Regulations governing the scope of the specific personnel affected and the measures required to take a urine test as described in the preceding Paragraph shall be determined by the Executive Yuan.
中文原文 毒品危害防制條例第33條
為防制毒品氾濫,主管機關對於所屬或監督之特定人員於必要時,得要求其接受採驗尿液,受要求之人不得拒絕;拒絕接受採驗者,並得拘束其身體行之。
前項特定人員之範圍及採驗尿液實施辦法,由行政院定之。

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