Using DeviceRequest.occurrence[x] element

Could you help me to find out if we can use DeviceRequest.occurrence[x] element to set the validity period of the request? or this particular element only indicates the usage schedule of the device that specifies in the DeviceRequest.code element?
In other words, which element is responsible for the period of validity of DeviceRequest?

A question about the context. Is the period of validity set by the author or by some regulation that is independent of the author?

occurrence[x] indicates the ‘ordered’ time - i.e. when should this device be used according to the order. It doesn’t reflect device availability. The ordered time could be influenced by regulation as well as by the author (as it is in pharmacy, where there’s often a ‘maximum’ allowed duration, but the ordering clinician might well tighten it further).