CHAPTER 9

BIOLOGICAL SAFETY

9.0 PROCEDURES FOR CENTRIFUGATION

 

9.1  Low-Speed Centrifugation

9.2  Microfuge Use

9.3  Centrifuge Spill

9.4  Decontamination Procedures


9.1       Low-Speed Centrifugation

All low-speed centrifugation must be done in capped tubes in centrifuge safety cups or centrifuge rotors which provide a gasket for containment.  Centrifuge safety cups must be used to be effective – if a tube breaks infectious material will stay in the bucket.  Buckets can be removed and opened in the biosafety cabinet.   

The following procedures should be followed during centrifugation:

·         Each operator should be trained on proper operating procedures

·         Keep a log book detailing operation records for centrifuges and rotors

·         Do not exceed safe rotor speed

·         Place a biohazard label on the centrifuge if used for infectious agents

·         Before centrifuging, inspect tubes for cracks and stress marks.  Avoid centrifuging in glass, if possible.

·         Make sure the correct adapters are in place

·         Fill and decant all centrifuge tubes and bottles within the biological safety cabinet. 

·         Wipe outside of tubes with disinfectant before placing in rotor.

·         Wipe the exterior of safety carriers or rotors with disinfectant before removing from the biosafety cabinet

·         Never overfill centrifuge tubes as leakage invariably occurs when the tubes are filled to capacity.  The maximum for general purpose centrifuge tubes/bottles is ¾ full.  Always cap tubes before spinning.

·         Stop the centrifuge immediately if an unusual condition (noise or vibration) begins

·         If decontamination of a rotor or bucket is required, soak rotor in Cavicide or equivalent disinfectant, followed by a mild detergent, then water rinse.

·         Always use sealed safety cups or sealed rotors with O-rings.  A variety of safety tubes/bottles and safety centrifuge cups have been developed specifically for work with infectious agents.

·         Decontaminate safety carriers or rotors and centrifuge interior after each use.

·         Wait 5 minutes before opening centrifuge lid after end of cycle.

 

9.2       Microfuge Use

Several models of microfuges are used in laboratories.  Microfuges should be placed inside a biosafety cabinet.  Microfuges with containment features may be used outside the biosafety cabinet, as long as the gasket in the rotor lid is in place and intact and the centrifuge lid does not open automatically when the cycle ends.

 

9.3       Centrifuge Spill

If leak is outside the safety cup or sealed rotor when opening centrifuge:

·         hold breath

·         close the centrifuge lid

·         turn centrifuge off

·         immediately leave the laboratory

·         notify others to evacuate the lab

·         post laboratory door with a biohazard spill note

·         presume the aerosolized material is contaminated

·         treat the incident as a potential exposure (call PI)

 

9.4       Decontamination Procedures

·         Allow area to rest for 30 minutes prior to entry for decontamination

·         Notify the supervisor or Principal Investigator and EHS Biological and Chemical Safety ext. 772-1781.  Do not re-enter laboratory for decontamination until the PI or EHS has authorized re-entry.

·         Don appropriate personal protection equipment (cover gown, booties, gloves, eye protection, respiratory protection) before entering the laboratory.

·         Use absorbent materials to cover spill areas before the addition of a disinfectant.  Absorbent material reduces the potential of generating an additional aerosol due to the decontamination procedure itself.

·         Decontaminate all exposed environmental surfaces before releasing the room for normal use.

·         Remove rotor and place in a biological safety cabinet.  To decontaminate the rotor, soak it in a disinfectant approved for use by the manufacturer’s instruction and followed by mild detergent, then water rinse.

·         All contaminated material will be disposed of according to procedures for the biosafety level of the laboratory. 

NOTE:  If unsure of procedure contact Environmental Health and Safety -Biological and Chemical Safety (extension) for information.