Design considerations

Because the Regulations do not call for any testing to demonstrate containment or shielding integrity, the design of excepted packages is not demanding. Almost any normal shipping package design could meet the requirements.

8.2.3. Examples

8.2.3.1. Radiopharmaceutical package

An example of an radiopharmaceutical excepted package is a cardboard and Styrofoam packaging containing small glass bottles filled with a liquid radioactive tracer, such as ¹²⁵I.

These typically have an activity of a few MBq, and are intended for such tests as endocrinology function or in-vitro cancer diagnosis. Figure 8.3 shows a typical radiopharmaceutical excepted package.

RADIOACTIVE RADIOACTIVE

FIG. 8.3. Excepted package containing radiopharmaceuticals

8.2.3.2. Postal package

A common type of excepted package is the postal package. The limits of content for postal packages are reduced by a factor of ten compared to other modes of transport (see paragraph 579 of TS-R-1). Typical uses of postal packages include the sending of radiopharmaceuticals for medical purposes.

Attention is drawn to the fact that the relevant national Postal Authority may impose additional requirements that are not covered by the IAEA Regulations. Therefore, their advice should always be sought prior to the design and production of an excepted package for postal use.

8.2.3.3. Instruments and manufactured articles packages

Another type of excepted package can be one containing instruments or manufactured articles such as clocks, electronic tubes or experimental apparatus containing radioactive material as a component part (paragraph 517 of TS-R-1).

Included in this grouping would be aircraft counterweights made from depleted uranium coated with epoxy resin, as well as uranium shielding encased in metal for X or gamma ray radiography sources and medical devices. The inactive sheath, which should cover all readily accessible external surfaces, is required to absorb the alpha radiation and to reduce the beta radiation at the surface. Such sheaths may also protect the outer surface from abrasion, and reduce surface oxidation thereby minimising possible build-up of loose surface

contamination. Although not a regulatory requirement, it is advisable to identify the contents of such packages so that they are not disposed of carelessly.

8.2.3.4. Empty packagings

Empty packagings which have previously contained radioactive material, and which represent a very limited radiological risk, may be transported as excepted packages (paragraph 520 of TS-R-1). This is allowed provided that:

- The package is in a well maintained condition and securely closed; and,

- The level of internal non-fixed contamination does not exceed 400 Bq/cm² for beta, gamma and low toxicity alpha emitters and 40 Bq/cm² for all other alpha emitters.

8.3. Industrial packages Type 1 (Type IP-1) 8.3.1. Requirements

Type IP-1 industrial packages have to meet the same general requirements (paragraph 621 of TS-R-1) as excepted packages discussed above in 8.2.1. If carried by air, they also have to meet the same additional requirements as excepted packages. Finally, an IP-1 package has to comply with the 10 cm smallest overall external dimension requirement (paragraph 634 of TS-R-1).

No tests are required by the Regulations for the Industrial packages Type 1 (Type IP-1).

8.3.2. Design considerations

Because the Regulations do not call for any testing to demonstrate containment or shielding integrity, the design of such packages is not demanding. Generally, anything sufficiently strong to hold the contents will suffice.

8.3.3. Examples

A common type of Industrial package Type 1 is a steel drum. Standard 100 L or 200 L drums, which are used in many industries, are used to transport uranium concentrates. These drums can also be used for the shipment of low level wastes that comply with the applicable requirements for LSA-I material.

Another common type of packaging might be a plywood box. This may have a plastic lining or could be steel banded for extra strength.

8.4. Industrial packages Type 2 (Type IP-2) 8.4.1. Requirements

8.4.1.1. General case

A Type 2 Industrial package has to meet all the requirements of an Industrial package Type 1 (Type IP-1) (paragraph 622 of TS-R-1).

In addition, Industrial package Type 2 designs have to be submitted to the free drop (paragraph 722 of TS-R-1) and the stacking test (paragraph 723 of TS-R-1) described in the next chapter. These tests are part of the normal conditions of transport tests. The criteria,

which must be met by the package following the tests, are that the package will prevent:

- Loss or dispersal of the radioactive contents; and,

- Loss of shielding integrity that would result in more than a 20% increase in the radiation level at any external surface of the package.

8.4.1.2. Alternative requirements

The Regulations allow the alternative use of United Nations packagings, tank containers, tanks and intermediate bulk containers (IBC’s), as well as the use of ISO freight containers (paragraphs 624-628 of TS-R-1). This is allowed provided that they fulfil additional requirements relating mainly to the loss or dispersal of radioactive contents, or to the loss of shielding integrity. These alternatives are summarized in Table 8.5.

The alternative requirements are considered as acceptable for two reasons. Firstly because the requirements and tests included in the United Nations Recommendations on the Transport of Dangerous Goods provide an equivalent level of safety. Secondly, (applicable to tanks and freight containers), because their extensive history of use has proved that they can provide safe handling and transport of LSA and SCO.

TABLE 8.5. THE USE OF SOME STANDARD PACKAGING AS ALTERNATIVES FOR IP-II OR IP-III

Package Substitution

IP equivalent Conditions for Allowed Package Substitution UN PG 1/II

packages (para 624)

IP-2 - Satisfies IP-1 requirements of para 621

- General UN recommendations on packing for Packing Groups I or II

Tank container (para 625)

IP-2 or IP-3 - Satisfies IP-1 requirements of para 621

- Meets UN multi-modal tank transport requirements or equivalent

- Minimum test pressure = 265 kPa - Retains shielding

Tanks (para 626) IP-2 or IP-3 - Satisfies IP-1 requirements of para 621

- Limited to LSA-I or LSA-II liquids or gases as prescribed in Table IV

- Excludes tank containers Freight

containers (para 627)

IP-2 or IP-3 - Satisfies IP-1 requirements of para 621 - Solid contents only

- Prevent loss or dispersal of contents and loss of shielding Interm. Bulk

containers (IBCs) (para 628).

IP-2 or IP-3 - Satisfies IP-1 requirements of para 621 - Metal construction only

- Conforms to UN design requirements for PG I or PG II IBC

- Drop tests on most damaging orientation 8.4.2. Design considerations

The mere fact that these packages have to be submitted to the free drop test means that they have to have a certain minimal strength, which must be consistent with the mass of the

package. However, such packages are not difficult to design. Generally, a package designed to withstand the free drop test can also easily withstand the stacking test.

8.4.3. Examples 8.4.3.1. Drums

A drum, filled with low level waste meeting the requirements of LSA-II material, may be transported as a package in its own right, or as a group of packages. Alternatively, for ease of handling, it can be transported inside an International Standards Organization (ISO) approved container. The use of an ISO container allows the option of declaring either the drums or the container as the packaging. Specifying the container as the package may provide some relaxation on the drum design, but may introduce other problems such as meeting the allowable quantities of fissile material in a package. Figure 8.4 shows a typical waste drum loading operation.

FIG. 8.4. Steel waste drum loading operation

8.4.3.2. Concrete cylinders

Ion exchange resin mixed with either cement or a polymer resin is often poured into a reinforced concrete cylinder to be used for final disposal. This constitutes a typical Industrial package Type 2 that can be used for transport.

8.5. Industrial packages Type 3 (Type IP-3) 8.5.1. Requirements

8.5.1.1. General case

In addition to the general design requirements of paragraphs 606-616 of TS-R-1

(discussed in 8.2.1.), industrial packages Type 3 must also meet several requirements (paragraph 623 of TS-R-1) that are essentially the same as those required for Type A package designs (contained in paragraphs 634-647 of TS-R-1). In summary, paragraphs 634-645 of TS-R-1 refer to:

- The smallest dimension not to being less than 10 cm;

- The use of seals to indicate opening;

- Tie-downs not interfering with the package’s ability to meet the requirements;

- The effect of specified ambient temperatures on packaging components and materials;

- Use of design and manufacturing standards;

- A containment system with a positive fastening device;

- Special form material potentially being part of the containment system;

- Separate unit containment systems also having separate positive fastening devices;

- Consideration of radiolytic decomposition;

- Ability to withstand reduced ambient pressure;

- Enclosures to retain any leakage from valves;

- Radiation shields designed to prevent unintentional release of components from the shield.

Industrial packages Type 3 have to be submitted (paragraph 646) to the tests designed to demonstrate ability to withstand normal conditions of transport. These are described in detail later in this Chapter, but include the water spray test (paragraph 721 of TS-R-1) preceding each of the free drop test (paragraph 722 of R-1), the stacking test (paragraph 723 of TS-R-1), and the penetration test (paragraph 724 of TS-R-1). The criteria that must be met by the package design following these tests and that the package will prevent are:

- Loss or dispersal of the radioactive contents; and

- Loss of shielding integrity that would result in more than a 20 % increase in the level of radiation at any external surface of the package.

As before, if being shipped by air the package must meet the requirements of paragraphs 617-619 of TS-R-1 (discussed in 8.2.1.).

Therefore, the requirements for a Type IP-3 carrying solid material are the same as those that apply to a Type A package carrying solid material.

Type IP-3 packages containing liquid radioactive material have to make allowance for ullage to address variations in temperature, for dynamic effects, and for filling effects (paragraph 647 of TS-R-1). However, the Type A package requirement of either absorbent material or a two-level containment system (paragraph 648 of TS-R-1) is not required for IP-3 packages designed for liquids.

8.5.1.2. Alternative requirements

The Regulations allow the use of some United Nations packagings under alternative requirements for Industrial Packages Type 3. (see paragraph 8.4.1.2. and Table 8.5 of this chapter). Figure 8.5 illustrates some typical Industrial Packages under the alternative requirements.

8.5.2. Design considerations

Since the requirements for Type IP-3 and Type A packages carrying solid radioactive material are the same, then many of the design considerations are similar. Often the material in the industrial package will have a lower specific activity and therefore, a Type IP-3 will be considerably bulkier.

8.5.3. Examples

Designers of Industrial package Type 3 frequently take advantage of the alternative that is allowed by the TS-R-1 Regulations. Consequently, a typical Type IP-3 is made of a 20 foot ISO container, with an internal stainless steel liner. The liner provides containment so that the internal part of the container can also be easily decontaminated. It is loaded with drums filled with Low Specific Activity (LSA) waste.