Central waste store for radioactive substances (ZAL)

In the "Central waste store for radioactive substances" (ZAL) radioactive waste from the hospital clinics and institutes is disposed of, in which open radioactive substances are handled. Waste disposal is subject to strict compliance with the legal provisions and in accordance with the principles of waste prevention, minimisation of waste volume, revaluation of radioactive substances and minimisation of waste costs.

Radioactive waste which arises in different areas of radiation is transported within the hospital to the ZAL and processed and managed further there. Subsequently radioactive waste is separated into decayable waste (radioactive waste which after an appropriate long storage time and clearance measurement cannot be disposed of as radioactive waste) and long-lived radioactive waste (radioactive waste with long half-life, is disposed of in NES Seibersdorf).

There is a tank facility with 26 steel tanks with a volume of 35m³, 17m³ and 6m³ as decay installation for the disposal of liquid radioactive waste. In the decay installation the radioactive waste water comes from the wards on the Clinical Department for Nuclear Medicine and the liquid radioactive waste from the Research and Routine Laboratory of the Hospital.

Radionuclide activity in the decay tanks is ascertained by means of gamma spectroscopy and scintillation measuring methods and the time it takes to decay is calculated by the time the end of release time is reached. Before the final discharge release with the waste water a control measurement is taken to guarantee that it is definitely below the discharge threshold.

The following radioactive waste is currently disposed of on a regular basis via ZAL:

• solid flammable waste
• solid non-flammable waste
• liquid radioactive waste
• biological waste
• enclosed radiation sources