Annex B

CLARIFICATION OF ITEMS ON THE TRIGGER LIST

(as designated in Section 2 of Part A of Annex A)

1.  Nuclear reactors and especially designated or prepared equipment and components thereof

1.1 Complete Nuclear Reactors

 Nuclear reactors capable of operation so as to maintain a controlled self-sustaining fission chain reaction, excluding zero energy reactors, the latter being defined as reactors with a designed maximum rate of production of plutonium not exceeding 100 grams per year.

 EXPLANATORY NOTE

A "nuclear reactor" basically includes the items within or attached directly to the reactor vessel, the equipment which controls the level of power in the core, and the components which normally contain or come in direct contact with or control the primary coolant of the reactor core.

It is not intended to exclude reactors which could reasonably be capable of modification to produce significantly more than100 grams of plutonium per year. Reactors designed for sustained operation at significant power levels, regardless of their capacity for plutonium production are not considered as "zero energy reactors".

EXPORTS

The export of the whole set of major items within this boundary will take place only in accordance with the procedures of the Guidelines. Those individual items within this functionally defined boundary which will be exported only in accordance with the procedures of the Guidelines are listed in paragraphs 1.2 to 1.10. The Government reserves to itself the right to apply the procedures of the Guidelines to other items within the functionally defined boundary

1.2 Nuclear Reactor Vessels

Metal vessels, or major shop-fabricated parts therefor, especially designed or prepared to contain the core of a nuclear reactor as defined in paragraph 1.1 above, as well as relevant reactor internals as defined in paragraph 1.8 below.

EXPLANATORY NOTE

The reactor vessel head is covered by item 1.2. as a major shop-fabricated part of a reactor vessel.

1.3 Reactor Fuel Charging and Discharging Machines

Manipulative equipment especially designed or prepared for inserting or removing fuel in a nuclear reactor as defined in paragraph 1.1. above.

 EXPLANATORY NOTE

 The items noted above are capable of on-load operation or of employing technically sophisticated positioning or alignment features to allow complex off-load fueling operations such as those in which direct viewing of or access to the fuel is not normally available.

1.4 Nuclear Reactor Control Rods and equipment

Especially designed or prepared rods, support or suspension structures therefor, rod drive mechanisms or rod guide tubes to control the fission process in a nuclear reactor as defined in paragraph 1.1 above.

1.5 Nuclear Reactor Pressure Tubes

Tubes which are especially designed or prepared to contain fuel elements and the primary coolant in a reactor as defined in paragraph 1.1. above at an operating pressure in excess of 50 atmospheres.

1.6 Zirconium Tubes

Zirconium metal and alloys in the form of tubes or assemblies of tubes, and in quantities exceeding 500 kg for any one recipient country in any period of 12 months, especially designed or prepared for use in a reactor as defined in paragraph 1.1. above, and in which the relation of hafnium to zirconium is less than 1:500 parts by weight.

1.7 Primary Coolant Pumps

Pumps especially designed or prepared for circulating the primary coolant for nuclear reactors as defined in paragraph 1.1. above.

EXPLANATORY NOTE

Especially designed or prepared pumps may include elaborate sealed or multi-sealed systems to prevent leakage of primary coolant, canned-driven pumps, and pumps with inertial mass systems. This definition encompasses pumps certified to NC-1 or equivalent standards.

1.8 Nuclear Reactor Internals

"Nuclear reactor internals" especially designed or prepared for use in a nuclear reactor as defined in paragraph 1.1 above, including support columns for the core, fuel channels, thermal shields, baffles, core grid plates, and diffuser plates. 

EXPLANATORY NOTE

"Nuclear reactor internals" are major structures within a reactor vessel which have one or more functions such as supporting the core, maintaining fuel alignment, directing primary coolant flow, providing radiation shields for the reactor vessel, and guiding in-core instrumentation.

1.9 Heat Exchangers

Heat exchangers (steam generators) especially designed or prepared for use in the primary coolant circuit of a nuclear reactor as de£med in paragraph 1.1 above.

EXPLANATORY NOTE  

1.10. Neutron detection and measuring instruments

Especially designed or prepared neutron detection and measufng instruments for determining neutron flux levels within the core of a reactor as defined in paragraph 1.1 above.

EXPLANATORY NOTE

The scope of this entry encompasses in-core and ex-core instrumentation which measure flux levels in a large range, typically fi'om 104 neutrons per cm2 per second to 10l° neutrons per cm2 per second or more. Ex-core refers to those instruments outside the core of a reactor as defined in paragraph 1.1 above, but located within the biological shielding.

2.. Non-Nuclear Materials for Reactors

2.1 Deuterium and heavy water

Deuterium, heavy water (deuterium oxide) and any other deuterium compound in which the ratio of deuterium to hydrogen atoms exceeds 1:5000 for use in a nuclear reactor as defined in paragraph 1.1 above, in quantifies exceeding 200 kg of deuterium atoms for any one recipient country in any period of 12 months.

2.2 Nuclear grade graphite

Graphite having a purity level better than 5 parts per million boron equivalent and with a density greater than 1.50 g.cm3 for use in a nuclear reactor as defined in paragraph 1.1 above, in quantities exceeding 30 metric tons for any one recipient country in any period of 12 months.

EXPLANATORY NOTE

For the purpose of export control, the Government will determine whether or not the exports of graphite meeting the above specifications are for nuclear reactor use.

Boron equivalent (BE) may be determined experimentally or is calculated as the sum of BEz for impurities (excluding BEcarbon since carbon is not considered an impurity) including boron, where:

 Ez (ppm) = CF x concentration of element Z (in ppm);

CF is the conversion factor: Oz x A}3) divided by (JB x Az);

(JB and (Jz are the thermal neutron capture cross sections (in barns) for naturally occurring boron and element Z respectively; and An and Az are the atomic masses of naturally occurring boron and element Z respectively.