The operation of various technical devices in hazardous enterprises is possible only with permission from Rostekhnadzor to use them. This document is issued both for single devices and for a whole batch of devices of a certain type, if they are produced in series. It can be issued to a set of devices, if they all perform related functions. The validity of the permit is 5 years, in some cases it is possible to issue a permit for the entire period, while these devices will be operated.