China has set a mandatory standard for plastic bags to curb its usage in the country.

Zhang Qiang is an official with the Beijing Municipal Bureau of Commerce.

"The bags must be at least 0.025 mm thick. According to the new standards, the bags must carry bar code and manufacturer's contact information on them, for the sake of supervision."

Plastic packages for fresh and cooked food are excluded from the standard to ensure their safety.

Retailers offering customers free or substandard shopping bags face heavy fines of up to a 10,000 yuan.

Li Xiaomei from Beijing Industry and Commerce Administration Bureau said they were taking several measures to make sure the new rules are implemented.

"We will first check whether the plastic bag markers and retailers have legal licenses and oversee the use of the bags to prevent substandard bags from entering the market. In the meantime, we need to raise people's awareness of environmental protection while shopping, and stop retailers from buying, storing, and providing ultra-thin plastic bags. Consumers also need to refuse such bags."

Experts say the regulation will help reduce China's plastic bag usage by two-thirds. They also urged the society to continue looking for environmentally-friendly substitutes for plastic bags.