Customers shopping at major department stores may be confused when the 50-cent levy on plastic bags takes effect next month, environmental officials admitted yesterday. They face having to make two separate payments for purchases, even at the same cashier counter, if they include both goods to which the levy applies and those to which it does not. Supermarkets, because of their size, must impose the levy regardless of the types of goods purchased, from July 7. But other retailers have to deal separately with prescribed goods - including food and drinks, personal care and beauty products and medicines and first aid items - and non-prescribed goods. Principal environmental protection officer Kenneth Chan Shu-to said some shops had already realigned their counters so there would be two machines at the same cashier handling the two types of goods separately. Shoppers would not have to queue twice at the cashiers if they had both types of goods to check out, although some minor problems were still expected, he said. 'They don't have to queue twice for their goods as the cashier will handle it flexibly. But it is possible that consumers might have to sign two separate bills as different machines will process different items.' Mr Chan said levy-free cashier counters would only provide bags in sizes just fitting the goods. He reminded shoppers not to ask for extra or bigger plastic bags at these counters to pack prescribed goods as this would cause the retailer to commit an offence. In a visit to a department store at City Plaza yesterday, Edward Yau Tang-wah, secretary for the environment, said he was impressed by the preparations by retailers and their staff for the introduction of the levy. He urged the public to try everything they could to minimise as much as possible plastic bag use and lead a greener life from next month. An average Hongkonger throws away about three plastic bags a day. 'There are many ways one can avoid the levy. They can simply bring their own shopping bags or put goods in the plastic bags already offered to them. Just save one more bag whenever it is possible,' he said. Mr Yau believed that sales would not be affected if most retailers enforced the law properly while shoppers' environmental consciousness was strong. Consumers are advised to pay attention to the signs posted at the cashiers about the levy arrangement and call a government hotline, 3187 0333, if they have doubts.