Table 2-3. Neutron Flux Dose Equivalents

TM 55-315

a. An exposure of 1 R because of X or gamma radiation.

b. A dose of 1 rad because of X or gamma radiation.

c. A dose of 0.1 rad because of neutron or high-energy radiation.

d. A dose of 0.05 rad because of particles heavier than protons and with sufficient energy to reach the lens of the

eyes.

e. If enough information exists to provide a reasonable estimate of the approximate distribution in energy of the

neutrons, the incident number of neutrons per square centimeter equal to 1 rem may be estimated from table 2-3.

2-41. Sievert (Sr)

A sievert is a unit, in the international system, of dose equivalence which is equal to 1 joule per kilogram. One Sv is

equal to 100 rem.

2-42. Special-Form Radioactive Material

Special-form radioactive material is any radioactive material that meets the following conditions:

a. It either is a single solid piece or is contained in a sealed capsule that can be opened only by destroying the

capsule.

b. The piece or capsule has at least one dimension that is 5 millimeters (0.197 inch) or greater.

c. It satisfies the test requirements for special-form radioactive materials outlined in 49 CFR 173.469. Special-

form encapsulations designed according to the requirements in effect on 30 June 1983 and constructed before 1 July

1985 may be used. Those designed or constructed after 30 June 1985 must meet the requirements outlined in this

paragraph.

2-43. Specific Activity

The specific activity of a radionuclide is the activity per unit mass of that radionuclide. The specific activity of a material

in which the radionuclide is essentially uniformly distributed is the activity per unit mass of the material.

2-44. Specification Container

Specification containers are approved containers or packages whose specifications are included in 49 CFR 178. These

containers are of two types - Type A and Type B packagings.

2-45. Specially Approved Containers

Specially approved containers are those containers that have been specially approved by the DOT. Each shipment using

a specially approved container is subject to the conditions specified in the pertinent permit or approval.

2-46. Transport Index

The transport index is the dimensionless number (rounded up to the first decimal place) placed on the label of a package

to designate the degree of control the carrier must exercise during transport. The transport index is determined as

follows:

a. The number rounded up to the first decimal place expressing the maximum radiation level in millirem per hour

at 1 meter (3.3 feet) from the external surface of the package.

b. For Fissile Class II packages or Fissile Class III packages, the number expressing the maximum radiation level

at 1 meter (3.3 feet) from the external surface of the package, or the number obtained

Table 2-3. Neutron Flux Dose Equivalents

No. neutrons per square

Average flux to deliver

Neutron energy

centimeter equivalent to a

100 mrem in 40 hours

dose of 1 rem (neutrons/cm2)

(neutrons/cm2 per second)

(MeV)

970 x 106

Thermal

680

0.0001

720 x 10

500

820 x 106

0.005

570

0.02

400 x 10

280

120 x 106

0.1

43 x 106

0.5

26 x 106

1.0

2.5

29 x 10

5.0

26 x 10

7.5

24 x 10

10 to 30

14 x 10

2-11