氢氟酸

qīng fú suān xún huán liú

氢氟酸循环流

hydrofluoric acid circulating flow

dāng shuǐ chéng qīng fú suān de nóng dù dī yú shí tā yǒu yán chí dà yú gè xiǎo shí de bào lù zhèng zhuàng

当水成氢氟酸的浓度低于50%时，它有延迟大于6个小时的暴露症状。

When aqueous hydrofluoric acid concentration is below fifty percent, it has delayed up to six hours symptoms of exposure.