Transport of Radioactive Material



Module No.:M2

TRANSPORT OF RADIOACTIVE MATERIAL

(Target audience: Senior Public Officials

Mode: All)

Scope

This module discusses the transport of radioactive material for various authorised applications of radiation. The module includes an introduction to radioactive materials and the uses of these materials in health care, industry and power production and certain consumer products commonly used in daily life. This module also discusses the need for the transport of radioactive material and the regulatory requirements which must be applied to ensure safety in the transport of radioactive material. The consequences of denial and delay of radioactive material shipments which comply with the applicable regulations are also included in the module.

The intended target audience for this module are Senior Public Officials concerned with all modes of transport viz., road, rail, sea, air and post.

What are radioactive materials?

Materials which emit radiation are called radioactive materials. Radiation is emitted as electromagnetic energy (gamma-radiation) or particles (alpha-, beta-, neutron-radiation).

Many substances in nature are radioactive. Granite, tobacco, some natural ores, milk, beer and many other products contain naturally occurring radioactive materials. In fact, all living organisms are continually exposed to radiation, which has always existed naturally. The sources of that exposure are cosmic rays that come from outer space and the surface of the sun ( cosmic radiation), naturally occurring radioactive material in the earth’s crust (terrestrial radiation), in building materials (e.g. ceramic tiles, concrete, marble) and in air (e.g. basements of buildings), water and foods (e.g. milk) and in the human body itself.

We have heard and read the names of materials such as iodine-131, technetium-99m, cobalt-60 and uranium-235 with symbols 131I, 99mTc, 60Co and 235U. These and other such materials are examples of radioactive materials. Some times they are called radioisotopes. Most of the radioactive materials are artificially produced.

What is the difference between radiation and a radioactive material? It is rather the same as the difference between fragrance and flowers! Radioactive materials emit radiation. Radioactive materials are used in many fields, namely, health care, industrial process control, quality control of industrial products, power production and consumer products in day-to-day use.

Uses of radioactive materials

Radioactive materials are very useful substances. However, the benefits they can provide are limited due to the useful radioactive properties gradually disappearing over time. As a consequence it is very important that these radioactive materials are shipped effectively and efficiently to reach their destinations in time, e.g. the waiting patient. They serve in many ways. Some examples are provided below.

Medical Diagnosis

We see in hospitals or in films or on the television, a patient undergoing a medical examination with a computer monitor showing pictures of the internal organs of the patient. The patient is first given some radioactive material orally or by injection. The material is directed to a specific tissue/organ which is to be examined. The doctor can view not only the organ under examination but also the functioning of the organ. That is, the doctor can see the insides of a patient’s body without surgery.

Every day over 75,000 such diagnostic procedures are carried out the world over. This number is increasing because the diagnosis is more accurate, faster, painless and cost-effective. Even children undergo these nuclear medicine procedures for a diagnostic study of heart, lungs, liver, kidney, thyroid, bone, intestines, brain, etc or detection of cancer.

Treatment of cancer

Large doses of radiation can kill cancer cells. With the ever-improving technology, more and more patients undergo radiation therapy. For thyroid cancer, radioactive iodine, called iodine-131, is administered to the patient. The radiation from a radioactive material called cobalt-60 is used for treatment of tumours. Over 45,000 treatments are carried out in more than 50 countries.

Sterilization of medical products

Large doses of radiation can kill germs. Single use medical supplies, such as syringes, gloves, cotton and bandages are sterilized using radiation from cobalt-60. Most first-aid kits found in our homes are sterilised by radiation. The products are exposed to radiation in a packaged condition. There is no need to repack them after sterilization. The products, after sterilization, are directly sent to the user. Thus, there is negligible chance of re-infection.

There are many more healthcare applications. For example, irradiated blood is used in life-saving blood transfusion as it reduces the risk of immunological reaction in the recipient.

Preservation of food

Enormous quantities of food grains, vegetables, spices, etc. are wasted every year due to infestation. This wastage can be stopped by treating food with large doses of radiation. Cobalt-60 is used for food irradiation. Many food products sold in super markets are sterilised by radiation. Food sterilisation has been approved by many countries and is encouraged by the World Health Organization (WHO).

Industrial Process control

Radioactive materials play a useful role in industrial process control. For example, the filling level of soft drinks or beer in metallic cans is controlled by passing the filled cans between a source of radiation and a radiation detector. The filled portion of the can stops the radiation and the unfilled portion allows all radiation through. The detector can find out the filling level. Such a device is called a level gauge.

The conventional methods of level detection are less effective. For determining the density of materials, for example, in the dredging of rivers and harbours, density gauges are used.

Thickness gauges are used for determining very precisely the thickness of metal sheets, plastic films, papers, etc. For exploration of oil and construction of roads, moisture gauges are used.

Industrial radiography

Defects in the welding and casting of metal objects are detected without damaging the objects by using a source of radiation. The principle is similar to the common diagnostic X-ray examination. The radiation source is kept on one side of the object being tested and X-ray films on the opposite side. A pressure vessel or an industrial boiler that has been tested by radiography assures high reliability and quality , e.g. radiography of welded pipe lines and castings. This kind of testing yields highly reliable results saving considerable cost and assuring the quality of the product.

Power production

Radioactive material (uranium compound) is used as fuel in nuclear reactors to produce clean and cost-effective power which provides lighting and heating to our homes, hospitals and work places, illuminates the streets, runs the trains, moves the elevators and escalators and enables the functioning of the communication systems.

Consumer products

Millions of smoke detectors operate all over the world providing early warnings of fires and thus saving lives and property. Smoke detectors use a small quantity of a radiation source. Dials painted with luminous radioactive compounds are in common use. The dials can be read in the dark. If a power failure occurs in a theatre hall and we have to rush out for safety how do we find the exit? The “Exit” sign could go off because of the power failure! Many of the “Exit” signs we see in public halls operate even if there is a power failure because they glow due to the radiation from the radioactive material inside the signs. Radioactive materials are used in fluorescent lamps for improved efficiency at low cost.

Other uses

Radioactive material is used for determining the soil quality for agriculture and to study nutrient uptake by plants. If we want to find out if a certain element, say, gold, is present in a sample given to us, using a very small quantity of radioactive material in a device, called an XRF analyser, we can detect not only the presence of the various elements present in the sample abut also the exact quantities in which they are present and very accurately too!

These are but a few of the uses of radioactive materials. As can be seen, radioactive materials are used in many fields. Not only hospitals and patients, but industrial establishments, agricultural scientists, manufacturers and users of the many industrial and consumer products and the many public utilities including communication systems operated by power delivered by nuclear plants depend on radioactive materials for the day-to-day necessities and conveniences.

Radioactive materials are integral to the quality of life today.

Why transport radioactive material

Radioactive materials are produced only in a few facilities in the world. From there the radioactive materials have to be carried to the user: a hospital, a factory, a power station or a home. Some of the radioactive materials have a short useful life losing their strength with time. (like a candle which burns down). They have to be rushed to the user. The radiation sources used in nuclear medicine are transported in small quantities by air. If they are not used within a short period they lose their radioactivity!

Consequences of delay

If the radioactive material is not delivered to the user in a timely manner the following consequences may result:

Patients are given appointments by hospitals and clinics well in advance and the supply of the radioactive materials is scheduled accordingly. If the radioactive material does not arrive on time, patients who may have travelled from far off places have to be turned away. They have spent time and money incurred in travelling. Many of them have spent on hotel accommodation. All that would be wasted. Most importantly, the diagnostic examination would be missed and the treatment that may be urgently warranted would be postponed.

Similarly, if a cobalt-60 source intended for a cancer therapy facility or a sterilization plant is not delivered on time, many patients will go without treatment, several tons of medical supplies or food products would miss radiation processing.

A delay in the delivery of fresh fuel to a nuclear power plant will result in reduced production of power. The consequences of reduced power are too obvious to warrant listing.

Regulations for transport of radioactive material

Transport of radioactive material is governed by international regulations. The IAEA has been publishing, for nearly half a century, Regulations which have been adopted by The International Maritime Organization (IMO) for transport by sea and the International Civil Aviation Organization (ICAO) for transport by air and other international organizations such as UN-ECE for road, rail and inland waterway transport in Europe (ADR, RID, ADN) and MERCOSUR/MERCOSUL in Latin America. These regulations specify –

▪ design safety standards for

o radioactive materials and

o packages;

▪ control measures during transport and

▪ approval requirements

The IAEA continuously reviews the Regulations and updates them as required.

Radioactive materials can be transported by post in conformity with the UPU requirements in quantities which are negligibly small.

The implementation of these regulations assures the safe transport of radioactive material for all modes of transport.

Package types

The strength, quantity and hazard of radioactive material determine the package type. The package types range from simple card board boxes ( e.g. excepted packages for radioactive material of low hazard) up to robust accident resistant packagings (e.g. Type B(U)/(M) packages for high level harard radioactive material). If a package has to carry high hazard radioactive material, the approval of the concerned Regulatory Authority is required.

Package information

How can you know that it is safe to handle a package? It is through labels on the package and documentation that packages communicate with the outside world.

The labels

▪ announce the package “Type”

▪ describe the contents

▪ indicate the radiation level outside the package and

▪ suggest emergency response needs.

The documentation which accompanies the package provides comprehensive details .

Involvement of public authorities

In addition to the competent authority for transport of radioactive material, other public authorities, may have responsibilities in connection with shipments of radioactive material e.g., Port Authorities, Civil Aviation Authorities, Customs and security agencies. Close coordination among the various public authorities including the competent authority for transport of radioactive material would ensure safe and efficient shipment in the interest of the public.

However, in some cases radioactive shipments which comply with the international transport regulations, are reported to have been delayed / denied.

The reported reasons include:

✓ There were additional requirements for handling radioactive cargo.

✓ The ports were in nuclear free zones! (Common radioisotopes used for healthcare and industrial applications are not nuclear materials.).

✓ A port would refuse to receive the vessel if radioactive material on board the ship was intended for use in the some other country.

✓ A port would not allow a ship in its waters even if the radioactive material on the board the ship was intended for use in its country!

✓ Ships carrying radioactive material would be allowed berthing in a port only if they arrive during daylight hours!

✓ Ships carrying radioactive material were accorded a low priority in a port.

✓ The competent authority for transport of radioactive material of a State considered that a shipment was safe but a port authority official of the same State refused the shipment because he thought it was not safe!

✓ Lack of harmonization between national and international regulations

✓ Lack of appropriate training on safe transport of radioactive materials

The public authorities can help improve the situation.

What can be done to facilitate safe uninterrupted movement of radioactive material

There are just a few producers of isotopes and millions of users world-wide. The purpose of transport of a radioactive material is to deliver the material to a user who may be a patient, a licensed industrial establishment or a power station or the manufacturer of a consumer product. In any case, the ultimate beneficiary is the common man. Radioactive materials are transported in accordance with international regulations assuring the highest standards of safety.

If your department proposes to introduce a requirement that may impose restrictions on transport of radioactive material, examine how best the objective of the proposal could be achieved without denying the society the benefits from the use of radioactive materials.

Effectively coordinate with the various authorities of your State.

Inform the other authorities and carriers in advance about deviations of your regulations and procedures from international practice.

Minimise such deviations.

Any delay or a denial of a shipment is going to result in patients being turned away; a factory or a nuclear power plant having to stop its legitimate operations; or a home being denied its right to use a safe product that would enhance the quality of life!

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