Are all lithium cells and batteries required to be mailed using surface transportation only if mailed separately from their equipment?

The requirement that all lithium cells and batteries must be mailed using surface transportation only if mailed separately from their equipment is based on safety regulations concerning the potential hazards these batteries can pose during air transportation. Lithium batteries are known to have a risk of overheating and possibly catching fire, which is why there are specific guidelines in place.

When these batteries are shipped separately, they cannot be transported by air due to the increased risk they present; thus, surface transportation is required to minimize the potential danger. This regulation applies universally to ensure the safety of the postal service and its employees, as well as the general public.

While there may be other conditions or exceptions for specific types of lithium batteries used in equipment or in certain situations, the general rule establishes the safest approach for handling lithium batteries when they are not in their intended devices.