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Research Compliance and Tech Transfer

Appendix E: Cell Sorter Guidelines and Standard Operating Procedures

This section establishes biosafety and operational requirements for the use of cell sorting instruments (e.g., flow cytometers equipped with sorters) that can generate aerosols during operation. These guidelines are intended to protect personnel, prevent environmental contamination, and ensure compliance with the Biosafety in Microbiological and Biomedical Laboratories (BMBL), 6th Edition, and the NIH Guidelines for Research Involving Recombinant or Synthetic Nucleic Acid Molecules.

Cell sorting instruments present a potential risk of aerosol exposure when sorting viable cells infected with or containing infectious agents, recombinant or synthetic nucleic acids, or other biological materials.

These procedures apply to all University of Montana research personnel and core facility users conducting cell sorting or analysis involving:

  • Human or nonhuman primate-derived materials (e.g., blood, tissues, or primary cells);
  • Risk Group 2 (RG2) infectious agents or materials potentially containing such agents;
  • Recombinant or synthetic nucleic acid constructs, including viral vectors (e.g., lentivirus, adenovirus, AAV) that require containment at BSL-2 or higher;
  • Unknown or uncharacterized samples that may contain infectious material.

All cell sorting involving potentially infectious or recombinant materials must be conducted under biosafety containment conditions appropriate for the biological agent and experimental design. The Institutional Biosafety Committee (IBC) and the Environmental Health & Safety (EHS) Biosafety Office determine the required containment level and facility configuration following a documented risk assessment.

Containment and Facility Requirements

Containment Level

  • BSL-2 containment is required for sorting viable cells infected with or containing RG2 agents, viral vectors, or human-derived materials.
  • Sorting of RG3 or Select Agents is prohibited unless conducted in a facility specifically designed and approved for such work.
  • BSL-1 containment may be appropriate for noninfectious, non-human materials following IBC review and risk determination.

Engineering Controls

  • All cell sorting of potentially infectious material must be conducted in an aerosol containment enclosure (ACE) or equivalent biosafety containment device.
  • The aerosol containment unit must maintain negative pressure relative to the laboratory and exhaust through HEPA filtration or directly outdoors.
  • Containment verification must be performed and documented at least annually, after maintenance, or following instrument relocation.
  • The aerosol management system (AMS) must be tested using the aerosol challenge test recommended by the manufacturer or institution.

Personal Protective Equipment (PPE)

Minimum PPE for BSL-2 sorting typically includes:

  • Lab coat or disposable gown
  • Gloves
  • Eye protection
  • Face protection (e.g., shield) when risk assessment warrants

Enhanced PPE may be required depending on the hazard assessment.

Training Requirements

Researchers must complete:

  1. Institutional BSL-2 training (or higher, as required)
  2. Instrument-specific training, provided by the cell sorting facility or core
  3. Any additional IBC-mandated training for work involving viral vectors or rDNA

Untrained personnel may not operate cell sorters handling BSL-2 materials.

Facility Responsibilities

Cell sorting facilities hosting infectious or recombinant materials must:

  • Maintain and document annual aerosol containment verification
  • Ensure sorters are located in appropriately rated laboratory spaces (BSL-2 or BSL-2+ as indicated by risk assessment)
  • Provide posted instructions for emergency shutdown and spill response
  • Maintain logs of decontaminations, maintenance, and incidents
  • Notify the IBC of equipment changes or relocation

User Responsibilities

Users approved to perform sorting must:

  • Follow all posted procedures and facility rules
  • Use only IBC-approved materials and adhere to biosafety levels assigned by the Committee
  • Notify the facility manager of any spills, incidents, or exposure concerns
  • Ensure samples are clearly labeled with the biosafety level and potential hazards 

Failure to follow IBC or facility requirements may result in suspension of cell sorting privileges.

Incident Reporting

Any spills, exposure events, containment failures, or unexpected aerosol release must be reported immediately to:

  • The Flow Core Manager
  • The Biosafety Officer