Ethics Guidelines
Part B - Guidelines for Projects Involving Ionising Radiation
Section 4 - Storage
In general, to minimise the effect on a radioactive materials store of fire or other major accident originating in the main building, it is preferable to locate the store as a separate building some metres away from any other building in the complex. It is generally possible to achieve this in Australia without unduly compromising other desirable attributes of a store, such as security or radiation levels external to the store.
It is recognised that in Antarctica the best compromise between competing requirements for a store may result in the store being within another building, particularly where the radioisotopes need to be kept in a refrigerator or freezer. In deciding on the location of the store, all the requirements of a store shall be kept in mind and a balanced assessment made where a compromise between competing requirements is necessary. The dangers of fire to buildings in the Antarctic should be particularly considered and the consequences of burning the store should be considered in relation to what will actually be kept in the store.
4.1 Each station shall be provided with one or more suitable storage areas where radioactive materials, when not in use, may be stored. On board ships the radioactive substances are to be stored away from any areas being used as clean areas for the measurement of naturally occurring radioisotopes. This may be in the radiation container laboratory.
4.1.1 Each storage area shall be exclusively for storage of radioactive material and shall not be used for general storage, and particularly not for storage of other hazardous substances, such as flammables, explosives or hazardous chemicals.
4.1.2 Each storage area shall be so sited as to be satisfactorily isolated from all food storage, food preparation or food consumption areas. (See also Section 4.4). Smoking, eating or drinking inside the store is prohibited.
4.1.3 The store shall not be used for other purposes (e.g. photographic darkroom, home brewing) than storage of radioactive materials.
4.1.4 Photographic films, particularly X-ray or high-speed emulsions, or other materials susceptible to degradation by ionising radiation, should not be stored in the vicinity of the store unless adequate shielding is provided, taking into account the actual radioactive contents of the store.
4.1.5 There shall be no upper or lower limit on the size of the store, provided that it fulfils the requirements of a radioactive store for the contents to be stored in it.
4.1.6 Access to the store shall be restricted to authorised persons and the store shall not be left unlocked.
4.1.7 The Site Radiation Safety Officer (RSO) shall also have responsibility for the safe storage of radioisotopes and operation of the radioisotope store. Where more than one project group is using the store, the store RSO shall be the Site RSO.
4.1.8 The Australian Antarctic Division (AAD) RSO shall be responsible for seeing that proper radiation safety is maintained in relation to storage at Kingston. The Site RSO shall be responsible for seeing that proper radiation safety is maintained in relation to storage in stores remote to Kingston. In particular, that the store is properly signed, routine safety checks are carried out and proper current records are kept. Both the AAD's RSO and the Site RSO are to keep researchers involved in natural abundance radioisotope measurement informed of all activities involving the usage of synthetic nuclides on the station or vessel.
4.1.9 The store shall be appropriately and conspicuously marked with a suitable warning sign made of durable material. The sign shall have a yellow background and black markings. The trefoil symbol shall form part of the sign together with appropriate wording. A typical example might be a large size trefoil and the word 'CAUTION' in large size letters together with the words 'STORE FOR RADIOACTIVE SUBSTANCES' in clear letters of more moderate size.
4.1.10 The store shall be constructed of durable materials and shall be designed to withstand severe weather conditions, such as blizzards. The store shall be so ventilated and constructed as to prevent the entry and build-up of drift within the store.
4.1.11 The store shall not be prone to flooding from any cause, whether the base water system or summer melt.
4.1.12 The materials used in the construction of the store should be fire resistant, and the amount of flammable material in the store should be minimised (e.g. uncontaminated flammable packaging, such as wooden crates, should be clearly marked as required packaging for radioisotopes and then stored elsewhere.)
4.2 Where radioactive gases may be emitted by stored sources, the store shall be adequately ventilated by mechanical means. Due to the desirability of excluding drift from the store and the problems of choking of ventilation ports by drift, this requirement will necessarily be subject to negotiation. For example, the port may normally be closed but will be opened and the store force ventilated for some minutes before entry into the store.
4.2.1 The air extraction system shall be installed so that it can be switched on from outside before a person enters the store.
4.2.2 The point of discharge for the extraction system should be well away from any occupied area and remote from any air conditioning intake.
4.2.3 An extraction system which is automatically switched on by the opening of the door should be considered.
4.3 The inside of the store shall be of such materials and so designed as to allow for easy decontamination.
4.3.1 Liquids in the store shall be stored with their containers in trays having sufficient volume to hold any liquid released through breakage or rupture of the container. This is particularly important where the liquid may freeze and expand if the temperature inside the store drops sufficiently. The trays should be made of a material that is easily cleaned and resistant to fire.
4.4 Refrigerators or freezers used to store radioactive materials should be used exclusively for that purpose and shall be kept locked and properly marked. Food or drink shall not be stored in the refrigerator/freezer. (See also Section 4.1.2).
4.5 Within the store, all containers shall be clearly marked with labels or tags on which the relevant information has been clearly printed, engraved or stamped. At very least the information shall include the radioisotope and its form, its activity, a relevant date related to the activity, the name and organisation responsible for the container. When the experiment is completed (or completed for that expedition or season so that there is a definite break or change in the experimentation), then a new label shall be prepared giving the activity remaining and the new relevant date. (The record keeping shall indicate the actual activity remaining at any time during the course of the experiment). Waste containers in the store shall also be appropriately labelled.
4.6 As soon as the stored source of radioisotope is no longer required, it shall be prepared by its user for return to Australia by packaging it in accordance with the 'Transport Code' (see Section 8). However, if the packaging material is flammable, the preparation shall take place but not the final packaging which should be stored elsewhere (after confirming that it is contamination free).
4.7 Dose rates in any occupied area shall be kept as low as reasonably achievable through any or all of the following means: location of the store - shielding of the containers within the store; shielding of the store itself - shielding of the occupied area.
Dose rates within the store and external to the store shall be kept as low as reasonably achievable, having regard for the time likely to be in and around the store by any individual.
4.7.1 The store Radiation Safety Officer shall survey and record the dose rates in and around the store and check and record the radiation levels at appropriate intervals. A radiation survey shall be carried out whenever there is any significant change in the contents of the store (i.e. any change in the contents in relation to penetrating radiation, such as gamma or neutron radiation).
4.7.2 Signs on the store shall indicate external dose rates where those dose rates exceed 2.5 uSv/hr. The dose rate external to the store shall not exceed 25 uSv/hr.
4.7.3 The Site RSO shall ensure that each user surveys and records the surface and one metre dose rates of that user's package(s) at appropriate intervals, where applicable. The survey shall be recorded and the information provided to the Site Radiation Safety Officer.
4.7.4 The Site RSO is responsible for ensuring that wipe test and/or contamination checks of the store are carried out at the start of the expedition, at the finish of the expedition, and at appropriate intervals in between. The Site RSO in stores remote to Kingston should, with the assistance of users, carry out such checks in relation to the store itself. The Site RSO and the AAD's RSO at Kingston should oversee such checks carried out by users on their respective containers within the store. Each user should do a contamination check prior to replacing the container in the store.
4.7.5 The store should not be used for drawing off quantities of radioisotopes. The user should take the container from the store and transport it in an appropriate manner (which may involve additional containment for transport) to the work area for drawing off. The container should then be checked for contamination and returned to the store. If any incident occurs during transport back to the store, the container should be re-checked for contamination.
4.8 All users are responsible for formulating appropriate radiation protection working rules and emergency procedures in relation to their respective operations. The Site RSO, in conjunction with users of the store, is responsible for formulating working rules and emergency procedures in relation to the store, and of coordinating the availability of user's survey instruments and protective clothing in order to implement the working rules and, if necessary, the emergency procedures.
4.9 Temporary field storage is likely to present particular problems and the standard expected of a permanent store is unlikely to be able to be maintained. Particular care with field storage is therefore indicated.
4.9.1 The temporary field store shall be maintained for only the minimum period necessary.
4.9.2 The quantities of isotopes stored in the field store shall be the minimum required.
4.9.3 The standard of containers in the field store shall be such as to minimise the risk of any inadvertent contamination occurring. The containers should preferably be containers meeting the requirements of field transport.
(ASP&C)
May 2002
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