Safety in the Laboratory


Biological Safety Cabinet


Working on samples under sterile conditions (protecting the experiment).
Protecting the experimentator against biological agents.


Risk of contamination by biological material

Minor risk of UV-exposure
→ UV-light should turn off automatically, when front window is open

Minor risk of gas or solvent explosion
→ gas burners should not be used inside of a safety cabinet
→ solvents (e.g. EtOH) should not be used extensively


see "SI Safety cabinet"
 Biohazard

Use disposable gloves:
→ protects experiment against contamination from the experimentators hands
→ protects experimentators hands when much EtOH have to be used for frequent hand disinfection during experimentation

 Gloves

Before starting the work:
Clean and sterilize cleanbench with 70% EtOH

Introduce only the absolut necessary material for the experiment
→ at this moment only UV-resistant material, not e.g. media or solutions

Close front window completely and turn on UV-light for 10 min for surface sterilization
→ longer times will not result in significantly better sterility
→ the life time of UV-lamps is limited and it is not visible when efficiency starts to reduce

Afterwards turn on blower, introduce missing material and solutions
→ spray all introduced materia with 70% EtOH

During the work
Never disturb laminar air flow, e.g. by Bunsen burner, too much material or fast movements

Never tap the vent slots at the front of the working area

Keep the front window as closed as possible during working

Do sometimes sterility test by incubating open agar plates for 1 h within the clean bench

Afer finishing work:
Get off all material

Clean cleanbench with 70% EtOH

Principle:

Working area
Not safe working area		 Safety cabinet class 1
Safety cabinet class 1		 Safety cabinet class 1
Safety cabinet class 1 aka cleanbench
Not steril air (red arrow) enters the system.
This air is sterilized by an HEPA-filter.
Sterile air (blue arrow) is blown over the experiment toward the experimentator.
With this air flow aerosols can be transported
    from the experiment to the experimenator

This protects only the experiment,
not the experimentator!		 Not steril air (red arrow) enters to the working area.
this ensures that areosols from the experiment will not leave the system.
Possibly contaminated exhaust air is steril filtrated by HEPA-filter.

This protects only the experimentator,
not the experiment!		 Not steril air enters the system (red arrow)
but is directed below the working area.
→ aerosols can not leave (protects experimentator).
→ vent slot should not be tapped (protects experiment)
behind working area not steril air is blown upwards.
2/3 of this air is steril filtrated (HEPA)
and blown laminarly to the experiment (blue arrow).
→ never disturb this laminar airflow!
1/3 is as exhaust air steril filtrated, too.

This protects the experimentator,
AND the experiment!







Back


Last modified: 01.10.2015