China's rehab centers will be required to notify in writing the families of inmates placed in isolation.

The rule comes into effect on June 1, according to a notice from the Ministry of Justice.

Centers are also required to give health checks to new arrivals and make records of any injuries, the notice states. These records must be signed by the police officer in charge and the addict.

Women who are pregnant, are breast-feeding or have given birth within the previous 12 months cannot be admitted into drug rehab centers, the notice adds.

Any inmate who participates in work for the center will receive payment and cannot work for more than five days a week, six hours a day.

Centers are also forbidden from releasing information on an inmate, the notice states.

If an addict dies during treatment at a center, workers should immediately notify the administrative authority and the family, the ministry said. It added that relatives who dispute the cause of death can appeal to the judiciary.