Special Requirements for Fissile Class Ill Shipments (49 CFR 173.457)

TM 55-315

(a) The transport index assigned in the package approval for nuclear criticality control purposes does not

exceed 10 for any single package;

(b) The total transport index for nuclear criticality control purposes for all packages in the shipment does

not exceed 100;

(c) The shipment satisfies the provisions of 49 CFR 173.441(b) if any package has radiation dose rates

that exceed 10 millirems per hour at 1 meter from any accessible external surface of the package; and

(d) The shipment will not be transported by water.

4-15. Special Requirements for Fissile Class Ill Shipments (49 CFR 173.457)

A Fissile Class III shipment may be made only according to a, b, or c below or according to other procedures authorized

by DOT. The transport controls must provide nuclear criticality safety and must be carried out by the shipper or carrier,

as appropriate, to protect against loading, storing, or transporting that shipment with any other fissile material.

a. Transport in a vehicle assigned for the sole use of that consignor, with a specific restriction for such sole use to

be provided in the special arrangements, and with instructions to that effect issued with the shipping papers; or

Except for aircraft shipments, transport under the escort of a person in a separate vehicle, with the escort

having the capability, equipment, authority, and instruction to provide administrative controls adequate to assure

compliance with this paragraph; or

c. Transport in a vehicle containing no other packages of radioactive material that must bear one of the

"radioactive" labels described in 49 CFR 172.403. Specific arrangements must be effected between shipper and carrier,

with instructions to that effect issued with the shipping papers.

4-16. Fissile Class Assignments and Evaluation of an Array of Packages (49 CFR 173.455 and 10 CFR 71.55

through 71.61)

The numerical values of package assignments as Fissile Class I, the transport indexes for Fissile Class II packages, and

the vehicle limitations for Fissile Class II packages must be determined according to paragraphs 4-10 through 4-13 and

this paragraph.

a. Specific Assumptions. Specific assumptions concerning the standards set in b and c below are:

(1) The fissile material is in the most reactive credible configuration, consistent with the damaged condition of

the package, the chemical and physical form of the contents and controls exercised over the number of packages to be

transported together.

(2) Water moderation occurs to the most reactive credible extent, consistent with the damaged condition of

the package and the chemical and physical forms of the contents.

b. Specific Standards for a Fissile Class I Package. A Fissile Class I package shall be so designed and

constructed and its contents so limited that:

(1) Any number of such undamaged packages would be subcritical in any arrangement, with optimum

interspersed hydrogenous moderation, unless a greater amount of interspersed moderation is in the packaging, in which

case that greater amount may be considered; and

(2) A total of 250 such packages would be subcritical in any arrangement if each package were subjected to

hypothetical accident conditions, such as free drop, thermal, and water immersion (specified and in the sequence listed in

para 4-10), with close reflection by water on all sides of the array and with optimum interspersed hydrogenous

moderation unless a greater amount may be considered. The condition of the package shall be assumed to be as

described in a above

c. Specific Standards for a Fissile Class III Shipment. A package for Fissile Class III shipment shall be so

designed and constructed and its contents, the number of packages, so limited that:

(1) The undamaged shipment would be subcritical with an identical shipment in contact with it and with the

two shipments closely reflected on all sides by water; and

(2) The shipment would be subcritical if each package were subjected to hypothetical accident conditions,

such as free drop, thermal, and water immersion (specified and in the sequence listed in para 4-10), with close reflection

by water on all sides of the array, with the packages in the most reactive arrangement, and with the most reactive degree

of interspersed hydrogenous moderation that would be credible considering the controls to be exercised over the

shipment. The condition of the package shall be assumed to be as described in a above. Hypothetical accident

conditions different from those specified in this paragraph may be approved by the US Nuclear Regulatory Commission if

the controls proposed to be exercised by the shipper are demonstrated to be adequate to assure safety of the shipment.

4-17. Special Requirements for Plutonium Shipments (49 CFR 71.63, AR 385-11)

a. Plutonium in excess of 20 curies per package shall be shipped as a solid.

b. Plutonium in excess of 20 curies per package

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