Biosafety levels

Biosafety level designations are based on a composite of the design features, construction, containment facilities, equipment, practices and operational procedures required for working with agents from the various microorganisms risk groups

 

 

 

safty-biology-biosafety-level-2020

Laboratory facilities are designated as: 

 

Biosafety Level 1: basic

Biosafety Level 2: basic

Biosafety Level 2+: BSL-2 laboratory with biosafety practices and procedures typically found at BSL-3

Biosafety Level 3: containment, as Level 2 plus special clothing, controlled access, directional airflow

Biosafety Level 4: maximum containment. As Level 3 plus airlock entry, shower exit, special waste disposal

 

For all Biosafety levels:

  • Pipetting should be only with mechanical advice
  • It is not permitted to eat or drink in the lab areas
  • Do not seal the biohazard bags; leave them loosely closed (opening of at least 5 cm)

 

 

 

 

 

Biosafety level (BSL)

BSL-1

BSL-2                   

BSL-2+                        

BSL-3                        

BSL-4

Description No containment Defined Unlikely to cause disease Containment                                    Moderate risk disease of varying severity Laboratories working with BSL-2 microorganisms levels with biosafety practices of BSL-3 level High containment Aerosol transmission Serious lethal/potentially disease Maximum containment Exoctic, high risk agents Life-threatening disease
Organisms E. coli, yeast Mammalian cells, tissue culture work, blood, human fluids, patient specimens, Influenza, HSV, HIV, Salmonellae, Hepatitis B, Listeria, infected animals with BSL-2 agents, Lyme Disease The risk assessment process, may determine that safety practices, over and above those required at BSL-2 needed for a research project, yet more complex BSL-3 laboratory facility is not necessary. Sars-Cov-2 for diagnostic (RT-PCR), blood from convalescence Covid-19 patients Tuberculosis, Sars-Cov-2 in tissue culture Ebola virus
Pathogen type Agents that pose minimal hazard potential to laboratory personnel & environment Agents associated with human disease Sars-Cov-2 for diagnostic (RT-PCR), blood from convalescence Covid-19 patients

Indiginous/exotic agents which present a potential aerosol trasmission, agents causing serious or potentially lethal diseases

 

  

 

 

 

Dangerous/Exotic agents that pose a high rusk of aerosol-transmitted laboratory infections, life-threatening disease

Treatment

 

Prophylactic treatment available Treatment available Depends on the pathogen    
Public access Not recommended Limit access to lab while BSL-2 work is being conducted Restricted The laboratory is separated from general traffic flow and accessed through an anteroom (double door entry or basic laboratory – Biosafety Level 2) or an airlock Located in a separate building or in a clearly delineated zone within a secure building. Entry and exit of personnel and supplies must be through an airlock or pass-through system
Bench-top work Permitted Permitted only for low risk procedures Not permitted Not permitted Not permitted
Personal protective equipment (PPE) Lab coat, gloves Lab coat, mask, gloves Disposable lab coat, N95 or N99 masks, face shield or half face mask, double gloves, disposable hat Protective clothing must be of the type with solid-front or wrap-around gowns, scrub suits, coveralls, head covering and, where appropriate, shoe covers, in addition to PPE in BSL-2 Ventilated and reusable pressurised protective suit (deathly viruses)
Decontamination/disinfection Autoclave and following any spill Autoclave daily and following any spill Autoclave dailly, immediately following work with biohazardous material, and following any spill Pass-thru autoclave with bioseal in laboratory room Pass-thru autoclave with bioseal in lab
Biological waste Biohazard bag Double biohazard bag Double biohazard bag

Laboratory room must be sealable for decontamination. Air-ducting systems

must be constructed to permit gaseous decontamination.

An autoclave for the decontamination of contaminated waste material should be available in the containment laboratory. If infectious waste has to be removed from

the containment laboratory for decontamination and disposal, it must be

transported in sealed, unbreakable and leakproof containers

 

A double-door, pass-through autoclave must be available in the laboratory area. Other methods of decontamination must be available for equipment and items that cannot withstand steam sterilization

Biological safety cabinet - BSC (HEPA Filter) Not required Required Required for all work with biohazardous agents

Biological safety cabinets should be sited away from walking areas and out of crosscurrents from doors and ventilation systems. The exhaust air from Class I or Class II biological safety cabinets, which will have been passed through HEPA filters, must be discharged in such a way as to avoid interference with the air balance of the cabinet or the building exhaust system

 

Class III biological safety cabinet, the supply air may be drawn from within the room through a HEPA filter mounted on the cabinet or supplied directly through the supply air system. Exhaust airfrom the Class III biological safety cabinet must pass through two HEPA filters prior to release outdoors. The cabinet must be operated at negative pressure to the surrounding laboratory at all times. A dedicated non-recirculating

ventilating system for the cabinet laboratory is required

 

Hand washing facilities

 

Required

 

Required

 

Required (foot, elbow)

Washing station with hands-free controls should be provided near each

exit door

Decontamination shower must be provided and used by personnel leaving the containment laboratory area. A separate personnel shower with inner and outer changing rooms is also provided
Storage equipment No biohazard signs required Biohazard signs required, all equipment must be labeled with contents Biohazard signs required, all equipment must be labeled with contents Biohazard signs required, all equipment must be labeled with contents Biohazard signs required, all equipment must be labeled with contents
Physical containment Decontaminate equipment immediately after use Use physical containment devices during procedures that have a high potential to create aerosols when using biohazardous material; Decontaminate immediately after use Use physical containment devices (centrifuge safety cup, sealed centrifuge rotor) for all activities using biohazardous material; Open containers in a BSC; Decontaminate immediately after use Consideration should be given to equipment such as centrifuges, which will need additional containment accessories, for example, safety buckets or containment rotors. Some centrifuges and other equipment, such as cell-sorting instruments for use with infected cells, may need additional local exhaust ventilation with HEPA filtration for efficient containment

Equipment such as centrifuges, will need safety buckets or containment rotors. Some centrifuges and other equipment, such as cell-sorting instruments for use with infected cells, may need additional local exhaust ventilation with HEPA filtration for efficient containment

 

 

 

 

 

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