Biological risk

As a researcher, you’ll probably be in contact with biological materials that have a known risk to people and the environment.

Research that is potentially biohazardous often includes these materials:

  • Microorganisms (bacteria, viruses and parasites) 
  • Human blood tissue and body fluids (human blood, serum, tissue and faecal specimens including FACS analysis). This can include cell lines of human or primate origin that are known to contain infectious viral agents. 

Work with Genetically Modified Organisms (GMO) requires statutory approval.

Keeping safe in the lab

Biohazardous materials can be infectious. Work must be carried out in labs that meet a minimum of PC1 containment with the following important considerations:

  • Work with biohazardous material is often confined within Class 2 Biosafety Cabinets. Laminar-flow cabinets are not suitable and must not be used for handling microorganisms.
  • Biohazardous waste must be disposed of properly.
  • Never use cells from staff or their relatives to generate cell lines, due to the high risk of exposure to transformed lines that are histocompatible.

Note: General guidelines for work with biohazardous material are provided further down this page.

Biological Risk Management Standard

This covers biological safety in addition to the requirements for containment as specified in HSNO and biosecurity requirements.

Read now: Biological risk management and containment standard.

1. Research involving microorganisms

The risks associated with the microorganisms, bacteria, viruses and parasites are dependent on their ability to:

  • Infect
  • Cause disease
  • And the availability of treatment for any
    laboratory-acquired disease.

These risks are codified in a number of risk classifications. We observe the NIH/CDC risk classification.

Find out more: NIH classification of biohazardous agents by risk group.

Prior approval

Work with any higher risk microorganisms (NIH/CDC risk classification of Risk Group 2 or higher) requires prior approval from the University’s Biological Safety Committee. This will ensure proper review of proposed procedures, training and oversight of work.

Learn more (staff only): Making applications for work with higher risk microorganisms.

2. Work with human blood tissue and body fluids

Unfixed human blood tissue and body fluids can potentially contain a variety of infectious agents so all must be treated appropriately and with care. Unfortunately the prevalence of the Hepatitis B virus in NZ is much higher than the equivalent in North America, Europe and Australia. The incidence of Hepatitis C is also high. 

Learn more about working with human tissue and faecal samples in the 'Use it' section of Risk Management and Containment:

Work with genetically modified organisms (GMO)

Any development or importation of genetically modified organisms requires prior Hazardous Substances and New Organisms (HSNO) approval and must be undertaken in a containment facility.

Explore more (staff only): Applying for the development or importation of genetically modified organisms.

General guidelines for working with biohazardous material

  1. Work must be undertaken in a laboratory that meets PC1 requirements at a minimum.
  2. Treat all human blood and body fluids, bone marrow, tissue culture and tissue specimens as if they were contaminated with an infectious agent.
  3. Avoid techniques which have a high potential for creating aerosols (for example, sonication, vortexing, blowing out pipette contents, centrifuging unsealed tubes).  Any aerosol generating manipulation must be carried out in a biohazard cabinet.  Sealed tubes must be used for centrifuging hazardous materials using sealed rotors or buckets. This is to minimise contamination in the event of tube failure.
  4. Use the appropriate containment conditions for your experiment, for example a class II hood for handling human material or a pathogen.
  5. Note that laminar flow cabinets are not suitable and must not be used for handling microorganisms.
  6. Disposable gloves must be worn when handling biohazardous materials. They must be disposed of into biohazard waste containers immediately upon conclusion of task. Care should be taken to prevent contaminated gloves coming in contact with laboratory furniture, doorknobs, telephones etc.
  7. Wherever possible use disposable pipettes and tubes rather than washing glassware.
  8. Contaminated material must be carried in a leak-proof container when being transported out of the laboratory.
  9. Contaminated recyclable glassware and equipment must be sterilised by autoclaving before being washed. Equipment that cannot be autoclaved must be decontaminated using approved decontamination agent.  Allow at least 30 minutes contact for proper decontamination.

View the University's protocols on the chemical decontamination of liquid biohazardous waste under the section 'Clean It' in Risk Management and Containment.

Decontaminating benchtops

  • Have a regular routine of cleaning and decontaminating bench tops and hood surfaces where biohazardous material is handled.
  • Use an approved decontamination agent.
  • Clean and decontaminate at least once a day. At all times, keep lab and bench tops clean. This especially applies to hood surfaces and ancillary rooms such as the cold room.
  • Keep the floors clear.

Read more about benchtop decontamination in the 'Clean It' section of the Risk Management and Containment page.

Segregate and dispose of all biohazardous waste correctly

  • Take appropriate precautions with contaminated sharps and needles. DO NOT RECAP NEEDLES. DO NOT SEPARATE NEEDLES AND SYRINGES. Dispose of intact needle and syringe by placing in an approved sharps container. Autoclave all other waste before placing in appropriate waste container.
  • Clearly label all biohazardous material and remove biohazardous labels from material that has been decontaminated. Do not use containers with printed biohazardous labels (eg, autoclave bags, sharps bins etc.) for other purposes.
  • Cupboards, refrigerators and freezers used for storing biohazardous material should be clearly labelled. They should indicate the nature of the material stored within and carry the universal biohazard sign.
  • Report immediately to the departmental safety officer any:
    1. Accident or any spillage of biohazardous material 
    2. Suspected infection (additionally, you should also report to the laboratory head).

Containment Equipment: Class II Hoods

  1. Risks caused by infectious organisms are reduced by handling these agents in specially designed Class II Hoods.
    Only Class II hoods provide both containment and a sterile work zone. Never use a laminar flow hood for handling biohazardous material.
  2. Work as far back in the hood as is comfortable to ensure proper containment of hazardous work. Be aware that some of the Class II hoods at the University do not comply with modern containment standards. If so, they are clearly marked as such. These hoods have been tested and comply with modified tests that assume work is carried out at least 75 mm from the air curtain. Work in these hoods must therefore never be allowed to come within 75mm of the front air grill.
  3. All waste generated in these hoods must be decontaminated by autoclaving or by treatment with chemical disinfectant prior to disposal. Ensure that approved biohazard bags are used to contain hazardous material.
  4. Flush hoods by continuing operation for ten minutes after use.
  5. Always leave hoods clean and tidy after use.

Guidance on hood placement and use

Learn more about biological safety cabinets in the 'Use it' section of Risk Management and Containment.

Biohazardous waste disposal

  • The following material must be autoclaved before disposal:
    • All material of human origin
    • Any material that has come in contact with a known pathogen.
  • Sharps (needles and syringes) must be disposed in approved sharps bins.
  • Used gloves should be disposed in medical waste (never in ordinary rubbish bins).

A summary of the information above is also available in the Laboratory Users' Quick Reference Guide and Decontamination Wall Chart in Risk Management and Containment.

Document Control
Version: 1.0
Last Updated: Dec 2019
Next Review: Dec 2022
Approver: Associate Director, Health Safety & Wellbeing