The World Health Organization is seeking public comment on its first attempt to create international shelf life policies for medical products.

In a draft guidance, the agency says drugmakers should set out expiration dates and those who buy medicines shouldn’t re-test the drugs to extend shelf life.

Occasionally, drugmakers may decide that their medicines should be re-tested after delivery, the agency says. But those products should have at least a year of shelf life remaining when they’re delivered.

The WHO hopes to strike a balance between making sure medicines are still potent and making sure they’re still available.