Acquisition and disposal of radionuclides
- It is intended that radioisotopes should be purchased in the quantities needed at a particular time, and not stored "For future use" unless purchase of small enough quantities is impracticable. This system is designed to ensure, as far as possible, that disposals cannot exceed permitted limits.
- No radionuclide sample may be brought to the University by any route without prior consultation with the Radiation Service to ensure that licence limits for holding and disposal are not exceeded.
- All radioisotopes must be ordered through the Radiation Service and will be received centrally (direct delivery will be made to theTremough Campus). Their arrival will be recorded, and each sample will be assigned a code reference and distributed by the Radiation Service to the end-user or designated representative at the laboratory of use, unless this is impracticable for any reason, when a registered radiation user (preferably the orderer or end-user of the radionuclide) will be asked to collect the sample and deliver it directly to the laboratory of use. At the Tremough Campus, Cornwall, delivery will be received via central reception and collected by the departmental RPS/responsible person. Delivery information will be transmitted to the URPO by the responsible person using e.mail, the URPO will then issue a record code number for that batch and records maintained at Tremough by the RPS as per Exeter
- A transmission form identified by the sample code reference must accompany the radionuclide sample from arrival to final delivery, being signed by each person who receives the radionuclide sample, until the form is signed by the end-user to signify receipt at the laboratory of use. The form must then be returned to the Radiation Service, this applies to Tremough Campus as well (copy back to URPO at Exeter).
- A form for recording the use and disposal routes of the radionuclide, identified by the sample code-reference, will accompany the sample, and must be kept up-to-date with accurate entries every time the radionuclide sample is accessed or used.
- Storage of the radionuclide will be in a locked facility within the laboratory area, cupboard or cold-store as appropriate, marked with the appropriate symbol and wording, and bearing the designated code-reference. The stock sample must not be absent from its store for any longer than is necessary for the purpose of the experiment, and it must be returned to its store at the earliest possible time.
- Aqueous waste will be disposed of via a designated disposal sink leading directly to a sewer. The disposal amount and rate will be controlled by the availability of radioisotope and the protocols of the experiments. Care must be taken to ensure that licence limits are not exceeded. If there is any likelihood of the limit being exceeded, the RPA must be consulted before any disposal action is taken, in order that a protocol may be devised to prevent contravention.
- Solid and non-aqueous waste will be collected at the storage facility on Streatham Campus. Each container of waste will be identified by a unique serial number, assigned by the Radiation Service, when it is taken into the waste store. Waste at the Tremough Campus will be collected and held within the appropriate departmental approved waste store.
- Very Low Level Waste (swabs, pipette tips, gloves, washed-out sample containers etc) must be collected in non-biodegradeable white or black plastic bags of suitable robustness, double-thickness, held in a suitable waste-bag support (for radiophosphorus this should be a purpose-made box of acrylic of minimum thickness 7 mm, with a lid) labelled to indicate that radioactive materials only must be disposed of there, and where separate waste streams are maintained, to identify which bag is for which waste type. The bags themselves should not be marked as radioactive. When a bag is full, the Radiation Service must be informed, and arrangements made to collect the bag with minimum delay. When it is collected, the bag will be marked with a radiation symbol which can be removed when it is finally disposed of.
- Each container of scintillation and other counted radionuclide samples must bear a radioactive warning sign and a legend identifying it as radioactive waste. It must have associated with it a schedule listing each disposal, with the activity disposed of, and a running total of activity in the container. When the container is full and passed to the Radiation Service for disposal, this schedule (or an exact copy thereof) must accompany the container at all times. On the container being taken into the waste store, the schedule will be assigned the same identifying code as the container to which it relates.
- Non-aqueous waste disposal routes are as follows:
- Dustbin waste - pipette tips, swabs, gloves etc - are collected in bags, recorded, checked for radioactive emission and placed in dustbins at a controlled rate.
- Rapidly-decaying isotope waste (Phosphorus-32 and 33, Cr-51, I-125) will be separated from other isotope waste and stored for decay to minimise environmental impact. When it has decayed for a suitable period (such that the activity is demonstrably below the statutory limits) it will be disposed of to dustbin.
- Scintillation waste will be disposed of regularly to our licensed disposer, Veolia Environmental Services(UK) Ltd, Southampton.