Lab Safety

Culture (Verb)

Verb: To intentionally grow microbes

Culture (Noun)

Noun: a population of microbes that has been grown

Growth Media

Liquid or solid medium containing nutrients for growth of microbes

Sterile

Absence of any living microbes

5 I’s of Microbiology

1. Inoculate

2. Incubate

3. Identify

4. Inspect

5. Isolate

Mixed culture

Growth media containing multiple species of microbe

Pure Culture

Growth media containing only one species of microbe

Primary pathogen

Pathogens that cause disease in healthy individuals

Primary Pathogen

Pathogens that cause disease in healthy individuals

Opportunistic Pathogen

Pathogens that cause disease in immunocompromised individuals

BSL Biosafety Levels

A metric to measure the threat level a microbe poses to lab workers who handle the microbes.

BSL 1-4, least to most hazardous

Biosafety Level 1

Non-pathogenic microbes or opportunistic pathogens that rarely cause serious infections.

Minimum requirements or a BSL 1 lab are:

Controlled environment, sharps container, sink, PPE, lab benches, optional is autoclave

BSL 1 Pathogens/Microbes

• Staphylococcus epidermis

  • causes infections, contaminates medical equipment

• Escherichia coli

  • gut flora

• Aspergillus niger

  • Fungi/mold, can cause lung infection

Biosafety level 2

Pathogens with:

1. Moderate risk of transmission, but are easily treatable

2. Low chance of transmission, but causes serious disease

BSL 2 Labs include everything a BSL 1 lab has, but autoclaves are required

BSL 2 Pathogens/Microbes

1. Moderate risk of transmission, but are easily treatable

   • Salmonella enterica serotype typhi (typhoid flu)

   • Staphylococcus aureus

1. Low chance of transmission, but causes serious disease

   • HIV human immunodeficiency virus

Biosafety level 3

Pathogens with significant risk of respiratory transmission and causing deadly disease/illness

Lab safety requirements:

• Everything BSL 1 and 2 Labs have

• Air tight environment when during disinfection

• Double door, secondary room to shower/equip PPE/disinfect

• HEPA Filter

• Decontamination system

• Ventilated hoods to manage microbes under; reduces bioaerosols

BSL 3 Pathogens/Microbes

• Mycobacterium tuberculosis

  • causes TB

• Bacillus anthracis

  • anthrax

• Yersinia pestis

  • plague

Biosafety level 4

Most dangerous, easily transmissible via aerosol, and frequently causes death. BSL 4 pathogens are not treatable, and vaccinations are unavailable.

Contains everything a BSL 1, 2, and 3 lab has- but needs:

• chemical and personal shower

• sealed penetrations

• positively pressurized PPE providing uncontaminated breathing air

  • punctured suit → air rushes out, minimized exposure to aerosols/pathogens

BSL 4 Pathogens/Microbes

• Ebola virus

• Lassa virus