BNIs are "nuclear activities", as defined by the Public Health Code, but are subject to specific regulation and supervision, owing to the significant risks of exposure to ionising radiation.

The operator is required to take all necessary steps to protect the workers against the hazards of ionising radiation, and more particularly to follow the same general rules as those applicable to all workers exposed to ionising radiation (annual dose limits, categories of exposed workers, definition of supervised areas and controlled areas, etc.), along with the technical and administrative requirements specific to BNIs (organisation of work, prevention of accidents, keeping of registers, medical monitoring of workers from outside contractors, etc.). The operator must also take the steps necessary to attain and maintain an optimum level of protection of the population, in particular by checking the effectiveness of the technical systems implemented for this purpose.

Under normal operating conditions, nuclear facilities discharge liquid and gaseous effluent, which may or may not be radioactive. The environmental and health impact of these discharges must be strictly limited.

The facilities must therefore be designed, operated and maintained in such a way as to limit the production of such effluent. It must be treated so that the corresponding discharges are kept to a level as low as reasonably achievable. These discharges may not exceed the limit values set on a case by case basis by the public authorities, using the best technologies available at an economically acceptable cost, and taking into account the particular characteristics of the site. Finally, these discharges must be measured and their actual impact regularly evaluated, in particular with regard to radioactive discharges, which are the one truly specific aspect of nuclear facilities.

When transporting radioactive or fissile materials, the main risks are those of internal or external exposure, criticality, or chemical hazard. Safe transport of radioactive materials relies on an approach called defence in depth:
- the package, consisting of the container and its content, is the first line of defence. It plays a vital role and must be able to withstand all foreseeable transport conditions;
- the transport medium and its reliability constitute the second line of defence;
- finally, the third line of defence consists of the response resources implemented to deal with an incident or accident.

The prime responsibility for implementing these lines of defence lies with the shipper.

Ionising radiation, whether generated by radionuclides or by electrical equipment (X-rays), is used in very many areas of medicine (radiology, radiotherapy, nuclear medicine), human biology, research, industry, but also for veterinary and medico-legal applications as well as for conservation of foodstuffs.

In terms of radiation protection, most of these activities - also considered to be nuclear activities - are the subject of a general system of licences or, as applicable, a special system of licences (case of BNIs, ICPEs and installations subject to the Mining Code) in which, on the basis of information forwarded by the licensee, the various radiation protection related aspects are examined, with regard to protection of both the workers and the population at large. Environmental protection is also taken into account through requirements applied to discharges of liquid and gaseous effluent. In the case of use for medical purposes, patient protection issues are also examined.

For activities other than those subject to the special systems mentioned above, the licences are issued to the persons responsible for use of the ionising radiation. The fact that the responsibility is targeted on the user in no way means that the head of the company is relieved of his duty to provide the person in possession of the sources with all resources necessary for radiation protection, be they human (person with competence for radiation protection, medical physics expert), technical (premises and equipment conforming to current standards) organisational, or measurements (dosimetry). Some activities (e.g.: radiology facilities) are simply subject to notification.