三廢 [ㄙㄢ ㄈㄟˋ; san1 fei4] three types of waste product, namely: waste water 廢水[ㄈㄟˋ ㄕㄨㄟˇ; fei4 shui3], exhaust gas 廢氣[ㄈㄟˋ ㄑㄧˋ; fei4 qi4], industrial slag 廢渣[ㄈㄟˋ ㄓㄚ; fei4 zha1] ◄ ►