Can Class A Health Certificate be used for Class B work?

I can't. A health certificate can be engaged in work directly related to food, while B health certificate can be engaged in tourism, culture and entertainment, beauty salons, and the two health certificates are not interoperable, so A health certificate cannot be engaged in B work. Health certificate refers to the proof of preventive health examination, which proves that the examinee has the health quality to engage in the prescribed business.