Lab safety & biosafety
BSL-1 covers agents not known to cause disease in healthy adults, on an open bench. BSL-2 adds a class II cabinet for anything that generates aerosols, controlled access, biohazard signage and decontamination of all waste. Human cell lines are handled at BSL-2 because they may carry bloodborne agents.
Our ruleSimulations prepare you for the bench but don't replace hands-on practice.
BSL-1 / BSL-2
BSL-1 covers agents not known to cause disease in healthy adults, on an open bench. BSL-2 adds a class II cabinet for anything that generates aerosols, controlled access, biohazard signage and decontamination of all waste. Human cell lines are handled at BSL-2 because they may carry bloodborne agents.
How it differs from the standard method
- BSL-2 work needs documented training and an approved assessment.
- Lab coats stay in the lab and are laundered there.
- Sharps are minimised: plastic instead of glass where possible.
1Containment is a system, not a cupboard
Working safely with biological and chemical hazards rests on three things: the facility (cabinets, hoods, ventilation, controlled access), the practices (how people actually work, from pipetting to waste), and the equipment people wear. They are applied in that order.
No known hazard to healthy adults
E. coli K-12, most plasmids. Open bench, standard microbiological practice, hand washing, no eating.
Moderate hazard by ingestion or injury
Human and primate cells, many clinical samples, lentiviral vectors. Class II cabinet, restricted access, decontaminated waste.
Serious airborne hazard
Agents such as M. tuberculosis. Dedicated facility, directional airflow, respiratory protection.
2The hierarchy of controls
- Eliminate or substitute: use a less hazardous reagent, or a kit instead of phenol-chloroform, if the science allows.
- Engineering controls: cabinets, fume hoods, interlocks, sealed rotors, sharps-free alternatives.
- Administrative controls: risk assessments, training records, standard operating procedures, signage, lone-working rules.
- Personal protective equipment: the last layer, chosen for the specific hazard and worn properly.
3What a biosafety cabinet actually does
A class II cabinet draws air in through a front grille, which forms a curtain protecting the operator, passes filtered air down over the work to protect the sample, and filters everything that leaves. Blocking the grilles with clutter, moving arms quickly, or working too close to the opening all break that air curtain. A cabinet is not a fume hood: it recirculates filtered air and does not remove volatile chemicals.
4When something goes wrong
The order is always people, containment, cleanup, report. Keep others away, allow aerosols to settle before approaching a spill, use the spill kit with the disinfectant your assessment specifies, work from the outside inward, and respect the contact time. Afterwards, report it even if nobody was hurt: the point of a report is to change what caused it.
Key terms
Practise these as flashcards →The written document that identifies hazards and sets the controls, containment, waste route and emergency plan before work starts.
A combination of facility, practices and equipment matched to the risk group of the agent.
A cabinet protecting operator, sample and environment with HEPA-filtered laminar airflow.
A ventilated enclosure that extracts chemical vapour away from the user; it does not protect sterility.
How long a disinfectant must stay wet on a surface to work.
Anything that can cut or puncture; contaminated sharps are the main injury route in a biology lab.
An incident that could have caused harm but did not; reporting it is how causes get fixed.
When to use it
- Before starting any new agent, cell line, vector or hazardous chemical.
- When inducting a new lab member, before they touch anything.
- After any spill, injury or near miss, to review what should change.
Compared with alternatives
The other thing to settle before an experiment starts.
Records of training, incidents and reagents are part of working safely.
Cabinet technique in day-to-day cell culture.
Protecting the cultures, as distinct from protecting people.
Sub-techniques
Choosing one here switches the whole page, including the protocol and the lab, to it.
BSL-1 covers agents not known to cause disease in healthy adults, on an open bench. BSL-2 adds a class II cabinet for anything that generates aerosols, controlled access, biohazard signage and decontamination of all waste. Human cell lines are handled at BSL-2 because they may carry bloodborne agents.
- BSL-2 work needs documented training and an approved assessment.
- Lab coats stay in the lab and are laundered there.
- Sharps are minimised: plastic instead of glass where possible.