Translate ES FR DE

Search

How Texas Biomed provides the highest level of BSL-4 safety

By Director of Biosafety Products David Wasescha and Marketing Communications Manager Scott Patterson

On May 03, 2023 in Case Studies

The risk of Ebola and other deadly pathogens being introduced into the community can be mitigated by working in a high-containment laboratory. As identified by the CDC Biosafety in Microbiological and Biomedical Laboratories, laboratories seeking to work with biohazardous materials must adhere to design requirements for their laboratories known as Biosafety Levels (BSLs for short). BSL-4 facilities have been recognized as the highest level of safety for researchers handling dangerous pathogens like filoviruses such as Ebola virus or Marburg virus. They are designed with the maximum amount of engineering controls designed to contain any potential release of infectious agents so that these cannot pose a threat outside the laboratory environment.

A biosafety level 4 lab is a place where scientists work with pathogens that can cause serious or potentially lethal disease

A biosafety level 4 lab is a place where scientists work with pathogens that can cause serious or potentially lethal disease. The CDC defines BSL-4 labs as those that handle "biological agents known to cause severe or potentially fatal illness in humans." These agents include Ebola, Marburg and Lassa fever viruses; variola (smallpox); Tularemia bacteria; botulinum neurotoxins; and plague bacteria.


BSL-4 facilities primarily rely on sophisticated engineering controls to ensure maximum containment of pathogens handled within the facility. At the core is the building itself, which must incorporate a series of containment properties including air locks, negative pressure rooms, and exhaust air that is completely filtered through HEPA filtration.

Personnel operating within a BSL-4 laboratory must also undergo heavy training prior to conducting work in the laboratory. Scientists working in any BSL-4 laboratory must follow strict protocols to ensure the safe handling and disposal of materials they come in contact with. Procedures should be approved by the CDC before being implemented at any facility handling dangerous organisms like Ebola or Marburg virus.

BSL-4 labs are the highest level of biocontainment, and they're only used for research on extremely dangerous pathogens. Texas Biomed maintains a BSL-4 lab that's rated as one of the best in the world.

The four types of BSL are based on how easily an infectious disease spreads and whether it's treatable or fatal. A lower number indicates less risk and more safety precautions:

  • BSL-1 facilities are laboratories that work with defined and characterized strains of viable biological agents not known to consistently cause disease in healthy adult humans.
  • BSL-2 facilities are laboratories in which work is performed using a broad-spectrum of biological agents and toxins that are associated with causing disease in humans of varying severity. BSL-2 biohazards are not known to be transmissible via the aerosol route, but are often handled in BSCs for added protection. These facilities require enhanced building and laboratory area requirements to ensure biohazardous assets are controlled.
  • BSL-3 facilities are laboratories in which work is performed using indigenous or exotic biological agents with a potential for respiratory transmission and those that may cause serious and potentially lethal infection. These facilities include all BSL-2 requirements, and regularly utilize negative pressure facility design, biosafety cabinets, and other containment means to ensure biohazardous assets are controlled. 
  • BSL-4 facilities are laboratories working with dangerous and exotic biological agents that pose a high individual risk of life-threatening disease that may be transmitted via the aerosol route and for which there is no available vaccine or therapy. All BSL-3 requirements apply, and BSL-4 facilities must also take specialized precautions such as total filtration of all exhaust air, the use of positive pressure bubble suits with Class II BSCs, and other requirements to ensure complete control of biohazardous assets.

Biosafety Cabinets (BSCs) ensure the safety of staff

BSL-4 facilities provide containment for individual users by using biosafety cabinets. Both Class II BSCs and Class III BSCs are found in BSL-4 laboratories. Facilities using Class II BSCs are most common.

A Class II BSC provides personnel, product, and environmental protection by creating a HEPA filtered work area with HEPA filtered exhaust. Access to the work area is made through a sash opening at the front of the cabinet. The cabinet maintains negative pressurization to keep biohazards contained. All exhaust air returns to the room only after HEPA filtration. A BSL-4 facility using Class II BSCs is known as a ‘suit laboratory’ and requires the use of a positive-pressure personnel suit.

A Class III BSC provides personnel and environmental protection with HEPA filtered exhaust. Access to the work area is made through gloves, as the work area of a Class III BSC is otherwise completely sealed. Some models may also have a laminar HEPA filtered work area to provide product protection. Class III BSCs operate under negative pressure, typically have double-HEPA filtered exhaust air that is further exhausted through the building exhaust, and have a transfer chamber into the cabinet that has an integral decontamination system. A BSL-4 facility using only Class III BSCs is known as a ‘cabinet laboratory’ and is less common. 

Bringing it All Together

Working with dangerous and exotic biohazardous requires extreme care. To conduct research with these agents at a BSL-4 designated facility with highly trained users and advanced engineering controls such as Class II BSCs. 

 

chevron_left Lyophilization, concentration or evaporation, which is best for my samples? Articles Forensic labs create a safer world with Labconco technology chevron_right