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BIOSAFETY – Four Biosafety Levels Designed to Protect Against Specific Biological Agents

25 June 2019

SIC Laboratory Equipment Repair

Biological agents are graded in levels of how dangerous they are.  Make sure you have got all the information you need to protect your staff, the environment, and the local community with a comprehensive guide to biosafety in the lab.

The Four Biosafety Levels
The four biosafety levels are designed to protect against specific biological agents, including bacteria, fungi, parasites, prions, rickettsia agents, and viruses.  Biosafety levels are designed to identify what safety measures should be in place for the agents a lab is using to prevent contamination.

Level I – The lowest level of biosafety and applies to agents that pose minimal threat and do not consistently cause illness in healthy adults.

Level 2 – The second biosafety level covers labs that are working with agents associated with human disease.

Level 3 – Applies to labs working with agents that are strictly controlled and must be registered with the appropriate government agencies.

Level 4 – Agents that pose a high risk of deadly disease require level four biosafety, to provide maximum protection and containment.


Level I
Research in these labs do not usually require specialty containment equipment and the labs themselves do not have the isolated from the general building.  Standard microbiology practices are usually sufficient to achieve successful containment.  Decontamination of work surfaces, spills, and materials are all important.  Standard personal protective equipment such as lab coats, gloves, and eye protection are sufficient.

Level 2
Often level 2 labs have a bigger focus on careful handling to avoid any injury that pierces the skin, as well as avoiding ingestion or mucus membrane exposure to contaminants.  An eyebath station should also be available.  Cautious handling of sharps and puncture-resistant sharps containers are also mandatory.  Labs with level 2 ratings should have a biosafety manual detailing required immunization and whether serum banking is required to protect staff.   A biosafety cabinet or equivalent device should be used for effective containment and an autoclave should be used for proper decontamination.

Level 3
Agents requiring level 3 biosafety are serious or lethal diseases that can be passed on through simple inhalation of particles or droplets.  Baseline serum samples should also be collected from all at-risk personnel.  Solid front wraparound gowns, scrubs suites or overalls, and respirators are necessary.  Access should be separate from general building corridors and incorporate self-closing double doors.  Ventilation should provide ducted, directional airflow from a clean area, with no recirculation.

Level 4
Level 4 requires complete clothing change before entry to a lab, a shower on exit, and decontamination of all materials before leaving the facility.  A Class III biological safety cabinet is required, and the lab should be completely isolated from the main building.  The lab should have dedicated supply and exhaust ventilation, with exhaust streams being filtered through high-efficiency particulate air filters.

In the event of a biosafety emergency, all the responsible bodies should be informed. Including the appropriate government departments.  Under RIDDOR (Reporting of injuries, Disease and Dangerous Occurrences Regulations) any incidents, accidents or infections involving biological agents at work, must be reported.

Scientific Instrument Center, Inc. certifies fume hoods, biosafety cabinets, and clean rooms.  Certifications are to meet ANSI/ASHRAE 100 for fume hoods and NSF 49 for biosafety cabinets.    Decontamination and all services can also be performed on biosafety cabinets, and fume hoods.  To inquire about our services, you may contact us or give us a call at (614) 771-4700.  We are here to answer any questions you may have.