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SOP-014: Cleaning and Disinfection of a Class II Biosafety Cabinet

Purpose​

To ensure that the Class II Biosafety Cabinet (BSC) remains clean, sterile, and suitable for mammalian cell culture by following standardized cleaning and disinfection procedures.

Scope​

This SOP applies to the routine cleaning and disinfection of Class II Biosafety Cabinets used for mammalian cell culture before and after laboratory procedures.

Responsibilities​

The operator is responsible for:

  • Cleaning the biosafety cabinet before and after each use.
  • Using appropriate disinfectants.
  • Removing biological waste and spills promptly.
  • Reporting cabinet damage or malfunction.

Required Materials​

Reagents​

  • 70% ethanol
  • Laboratory-approved disinfectant (if required)

Equipment​

  • Class II Biosafety Cabinet
  • Lint-free wipes or sterile disposable wipes
  • Biohazard waste container

Procedure​

1. Prepare the Cabinet​

Ensure that all cultures, reagents, and waste have been removed from the cabinet.

Inspect the work surface for spills or debris.

2. Clean Interior Surfaces​

Using lint-free wipes moistened with 70% ethanol or an approved disinfectant, clean the following surfaces:

  • Work surface
  • Side walls
  • Back wall
  • Interior glass sash (accessible portion)

Clean from the cleanest area toward the dirtiest area.

3. Remove Residues​

If spills or dried residues are present, remove them carefully before final disinfection.

Avoid using abrasive materials that may damage cabinet surfaces.

4. Disinfect Equipment​

Disinfect reusable laboratory equipment before removing it from the cabinet.

Discard disposable items into the appropriate biohazard waste container.

5. Final Disinfection​

Perform a final wipe of the work surface and interior surfaces.

Allow the disinfectant to remain on the surfaces for the recommended contact time.

6. Complete the Procedure​

Leave the cabinet clean and free of unnecessary materials.

Return the cabinet to standby or operating mode according to laboratory policy.

Acceptance Criteria​

ParameterAcceptance Criterion
Work surfaceClean and free of visible residue
Interior surfacesProperly disinfected
WasteRemoved from cabinet
Cabinet conditionReady for the next user

Critical Control Points​

  • Perform cleaning before and after each cell culture session.
  • Observe the recommended disinfectant contact time.
  • Avoid excessive liquid that could enter cabinet openings.
  • Never block airflow grilles during cleaning.
  • Use only laboratory-approved cleaning agents.

Documentation​

Record the following when required:

  • Date
  • Cabinet identification
  • Cleaning completed
  • Operator initials
  • Any abnormalities or maintenance needs

Quality Control​

Verify:

  • Interior surfaces are visibly clean.
  • No biological waste remains inside the cabinet.
  • Cabinet airflow openings are unobstructed.
  • Cleaning supplies are suitable for laboratory use.

Troubleshooting​

ObservationPossible CauseCorrective Action
Persistent stainsDried biological materialClean with an appropriate laboratory-approved disinfectant and repeat if necessary
Sticky residueDisinfectant buildupWipe with sterile water if recommended by laboratory procedures
Visible debris after cleaningIncomplete cleaningRepeat cleaning before using the cabinet
Cabinet damage observedMechanical wear or accidental damageReport the issue and discontinue use if cabinet integrity is compromised

Safety Considerations​

  • Wear appropriate personal protective equipment (PPE).
  • Handle all waste as potentially biohazardous.
  • Use only disinfectants approved by institutional policy.
  • Dispose of contaminated cleaning materials as biohazardous waste.
  • Report spills involving hazardous materials according to laboratory procedures.