A B C D E F G H I J K L M N O P Q R S T U V W X Y Z

O

occupational exposure:
See exposure, types of.

off-site:
Outside the site area.

on-site:
Within the site area.

operating conditions:
See operational states.

operating organization:
1.   The organization authorized by the regulatory body to operate a facility.

! Note that it may be the operating organization before operation starts.

In practice, for an authorized facility, the operating organization is normally also the licensee or registrant.  However, the separate terms are retained to refer to the two different capacities.
2.   The organization (and its contractors) which undertakes the siting, design, construction, commissioning and/or operation of a nuclear facility.
This usage is peculiar to waste safety documentation, with the corresponding understanding of siting as a multistage process.  This difference is partly a reflection of the particularly crucial role of siting in the safety of repositories.

operating personnel:
Individual workers engaged in the operation of an authorized facility.

! This may be shortened to operator(s), but only if there is no danger of confusion with operator in the sense of operating organization.

operation5:
All activities performed to achieve the purpose for which a facility was constructed.
For a nuclear power plant, this includes maintenance, refuelling, in-service inspection and other associated activities.

operational limits and conditions:
See limit.

operational states:
See plant states.

operator:
Any organization or person applying for authorization or authorized and/or responsible for nuclear, radiation, radioactive waste or transport safety when undertaking activities or in relation to any nuclear facilities or sources of ionizing radiation.  This includes, inter alia, private individuals, governmental bodies, consignors or carriers, licensees, hospitals, self-employed persons, etc.
Synonymous with operating organization.
Operator is sometimes used to refer to operating personnel.  If used in this way, particular care should be taken to ensure that there is no possibility of confusion.

optimization:
The process of determining what level of protection and safety makes exposures, and the probability and magnitude of potential exposures, "as low as reasonably achievable, economic and social factors being taken into account" (ALARA), as required by the ICRP System of Radiological Protection.

! This is not the same as optimization of the process or practice concerned.  If there is any danger of ambiguity, a more explicit term such as ‘optimization of protection (and safety)’ should be used.