XVII. FacilitiesA. Work Areas
Portions of the laboratory should be designated as radioactive material work areas. Keep these areas isolated from other non-radioactive areas in order to reduce the likelihood of the spread of contamination. The radioactive material work areas should be clearly labeled and laboratory personnel not working with radionuclides should be restricted from these areas. Yellow and magenta rope, ribbon or tape and appropriate warning signs may be used for this purpose. These may be obtained from the R.S.O.
All radioactive material under the control of an RI shall be stored in a secure, lockable storage area. If more than one user shares a common facility, all radioactive material belonging to each RI shall be segregated in such a way that accidental transfer of material is unlikely.
C. Fume Hoods
A fume hood is necessary when working with volatile radionuclides (iodine) or when heating or stirring solutions containing radioactive materials. All work should be performed in a hood that has a capture velocity of 100 linear ft. / min. measured at a sash height of 18" and at least 60 linear ft./min. fully open.
Desirable characteristic of rad material fume hoods:
- The hoods should be designated as a Radioisotope Fume Hood by the vendor.
- The interior should be one-piece, seamless material, with covered corners free of joints, cracks or gaskets. The preferred material is stainless steel.
- Ducts should be of stainless steel. Each hood should be ducted independently directly to the roof.
- Blowers should be roof-mounted, spark-proof, explosion-proof units.
- A HEPA filter should be used in the exhaust duct if the unit is to be heavily used for radioisotope work.
- New units should have an air motion sensor and alarm to ensure proper air velocity and direction. Older units should have, at a minimum, a signal light to show that the motor is receiving power.
- When possible locate hoods in areas that would not have to be passed in order to exit in case of an emergency. As much as possible, locate hoods in a draft-free, low-traffic area. If ceiling mounted vent ducts terminate directly over a fume hood, provisions should be made to deflect the incoming air away from the fume hood opening.