Nanjing City, the validity of health permits and review time limit is as follows: food hygiene license is valid for 3 years (small certificate, site canteen certificate is valid for one year), an annual review; public **** place health license is valid for 3 years, every two years, a review; drinking water health license is valid for 4 years, a review every year; dry cleaner's health license is valid for 2 years, a review every year; Medical institutions health license is valid for 5 years, an annual review; radiation device work permit is valid for 3 years, every 165 years review.