International Atomic Energy Agency Information Circular (Unofficial electronic edition)

INFCIRC/26/Add.1 9 April 1964 GENERAL Distr. Original: ENGLISH

On 26 February 1964 the Board of Governors approved provisions to extend the Agency's safeguards system to make it relate to reactors of 100 or more thermal megawatts, notwithstanding the limitations specified in paragraph 4 of document INFCIRC/26. The present document sets forth these provisions for the information of all Members.

A. Introduction
The safeguards provisions set forth in document INFCIRC/26 (hereinafter referred to as the "principal safeguards document"), except those in sections V.B and C thereof and as otherwise specified herein, will also apply to reactors of 100 or more thermal megawatts and to the source and special fissionable material used or produced in them. The following additional provisions relate to reactor facilities of 100 or more thermal megawatts and also to other reactor facilities to which the table in paragraph 65 of the principal safeguards document does not extend (together hereinafter referred to as "large reactor facilities").
B. Attachment to special fissionable materials produced in large reactor facilities
The provisions for the attachment of safeguards contained in the principal safeguards document and in paragraph 3 below will relate to all generations of special fissionable material derived from special fissionable material produced in a large reactor facility, notwithstanding any provision to the contrary in that document. The procedures of application will be in accordance with the safeguards procedures in effect at the time of such application.
With respect to a large reactor facility to which Agency safeguards are not attached, Agency safeguards will be attached at least to such fraction of the special fissionable material produced in the reactor as is equal to the ratio of the fissionable isotopes ("fissionable isotopes" means the isotopes uranium-233, uranium-235 and plutonium-239) within the nuclear material to which Agency safeguards are attached to all fissionable isotopes in the reactor. If this ratio is greater than 0.3, safeguards will be attached to all such material produced in the reactor. The ratio will be calculated on the basis of estimated average values for the period specified in the appropriate agreement. (This paragraph constitutes an interpretation of paragraph 35 of the principal safeguards document).
C. Procedures to supplement those in section V.A of the principal safeguards document
(a) Routine reports
The required frequency of routine reports for a large reactor facility shall not exceed twelve a year.
If requested, the State shall make available to the Agency progress reports on the construction of a large reactor facility, starting when construction has reached an advanced stage as specified in the appropriate agreement. These reports shall provide such information on the current condition of the facility as is relevant to the application of safeguards, and a forecast of the further work planned for the following four-month period. Not more than four such reports shall be required annually.
(b) Frequency of routine inspections
The maximum frequency of routine inspections during and after the construction of a large reactor facility shall be as shown in or as obtained by extrapolation from the table in paragraph 65 of the principal safeguards document. If such extrapolation indicates a frequency in excess of twelve per year, the Agency's inspectors shall have access to the facility at all times. In determining the inspection requirements for a particular facility, due account shall be taken of paragraphs 63 and 64, and of the considerations in subparagraphs (a) to (d) of paragraph 65, of the principal safeguards document.