Radioactive material

Following these basic safety concepts, it is important first to accurately characterize the radioactive material that is planned for shipment. The various possibilities were introduced in the previous chapter on terminology. The factors that need to be known in order to characterize the radioactive material include:

- the form (special form or not);

- the applicable A1/A2 value;

- the A2/g value; and

- the nature of the material itself (e.g. instrument or article, surface contamination, combustibility, fissile properties, irradiated fuel, UF6, and other dangerous properties).

The derivation of A1/A2 values and their application to material types are the subjects of Chapter 6.

Knowledge of the factors listed, along with the quantity of radioactive material that

Continuing with the basic safety theme, material that is exempt from the Regulations (see Section 4.3) clearly falls under the inherently safe criterion. The same can be said for material that can be shipped in excepted packagings. In addition, the nature of LSA-I is such that it would be very difficult to ingest or inhale sufficient quantities to cause a radiological problem. More hazardous material types however, need to progressively rely on the packaging for some aspects of safety.

5.3. Packages

The correlation between the three conditions of transport discussed earlier in 5.1.2.

and the eight basic packaging types is an important aspect of the safety built into the Regulations. Table 5.1 just gives the broad overview.

TABLE 5.1. CONDITIONS OF TRANSPORT ASSOCIATED WITH DIFFERENT PACKAGES

Conditions of transport Type of package

Routine Excepted; Industrial Type IP-1, -2 and -3; Type A; Type B(U) and Type B(M); Type C

Normal Industrial Type IP-2 and 3; Type A; Type B(U), and

B(M); Type C

Accident Type B(U) and Type B(M); Type C

Since packages are very much the key to the Regulations, information on them is found in several sections of TS-R-1. The contents limits and material restrictions for the different types of packages are defined in Section IV. The requirements for packagings and packages, including the tests needed as well as the pass criteria, are presented in a hierarchical fashion in Section VI of the Regulations. These build from the "General requirements for all packagings and packages” (TS-R-1 paragraphs 606–616) to “Requirements for packages containing fissile material” (TS-R-1 paragraphs 671–682). The specific procedures for all of the tests referred to in Section VI for the various types of package designs are specified in a similar fashion in Section VII of the Regulations.

Because of this method of presentation in the Regulations, it is sometimes difficult to gain a general overview of the requirements applicable for all of the packages. For this reason, information on packages is presented differently in this training manual. Following the general philosophical introduction given here, the package types, their limits, and typical contents are covered in Chapter 7. The requirements, design considerations, and examples of packages are given in the Chapter 8. In Chapter 8, the Figures 8.1 and 8.2 and the Tables 8.1, 8.2, 8.3 and 8.4, have been developed as a summary of much of these data. The figures and tables provide at a glance both the requirements needed for a particular package type as well as the package types for which a particular requirement is applicable. Because there is always more detail in the Regulations than can be provided in the table, the relevant paragraphs are given for reference. Tables 8.2, 8.3 and 8.4. provide a general and a detailed listing of the requirements for all package types from excepted packages to Type C packages. They also include a summary of the test procedures that apply. These three tables can be used to assist in understanding the hierarchical nature of requirements imposed on package designs following the basic philosophical principles discussed in this chapter. Finally, detailed information about the package tests, and how to perform them, is provided in Chapter 8.

It should be noted that the additional considerations for packages containing fissile material are covered separately in Chapter 11.

5.4. Optimization

Optimal practice in radioactive material transport involves seeking the best combination of material type and packaging, as well as considering other factors such as exclusive use and conveyance. Sometimes the radioactive material to be shipped can be characterized to meet more than one of the definitions of material given in the Regulations. In addition, there is often more than one packaging type that may be used. This is especially true if the radioactive material can be split into smaller lots.

Since the Regulations have been designed with the safety principles discussed above, the minimum allowable packaging and transport methods should be used. For example, there is nothing in the regulatory requirements to prevent shipping some radioactive material with an activity totalling 0.5 A2 in a Type B(U) packaging. However, this is clearly excessive and expensive. The material could almost certainly be shipped more economically in a Type A packaging. Moreover, depending on a number of other factors, it might even be transportable in an industrial package as one of the LSA or SCO categories.

There are many advantages to be gained from optimally characterizing the radioactive material to be shipped and selecting the best packaging and transport options. This is the art of radioactive material transport. However, it can only be practised effectively when one has a complete knowledge of the Regulations.