ThermoFisher Scientific HERASAFE 2025, Operating Instructions Manual

Page: 59 / 76

Herasafe 2025 50161258 | 59
Cleaning and Decontamination |
Chapter 9
UV Disinfection after a Wipe/Spray
Disinfection
An UV disinfection can be performed either by using the optional integral UV lamps. The run
time of the routine can be preset with the operating panel.
UV Disinfection using the integral UV Lamps
Running the UV disinfection routine, see page 49
.
Changing the UV Disinfection Time
Setting the run time for the UV disinfection, see page 48.
Disinfection with Formaldehyde
A suitable disinfection procedure must be selected according to the scope of application
of the safety cabinet.
One possible method based on EN 12469/2000 is described below.
To cover the spectrum of action A, B, C and D, it is necessary to use another method.
Based on recommendations of the RKI (Robert Koch Institute), another disinfection
procedure is described in the service manual.
Procedure in accordance to EN 12469 / 2000:
For gas disinfection, formaldehyde is evaporated in the sample chamber of the completely
sealed cabinet. The quantity of the formaldehyde used depends on the sample chamber
volume of the cabinet version to be disinfected (see “Technical Data” on page 67). Per
cubic meter of sample chamber volume, at least 5 g formaldehyde must be evaporated
with 20 ml water (corresponds with 25 ml of a 20 % formaldehyde solution). The
formaldehyde evaporates immediately when its boiling point is reached. The required
reaction time is at least 6 hours.
After the required reaction time, the formaldehyde should be neutralized by evaporating a
25 % ammonium solution (10 ml per cubic meter of sample chamber volume).
NOTE
Before disinfection remove the UV side covers and replace them afterwards.
Do not apply too much cleaning agent to the UV emitter box. The ground fault
circuit interrupter may release.
NOTE Disinfection procedure
Disinfection with formaldehyde bears considerable risks, the procedure must
only be performed by specially trained authorized service personnel and in
accordance to national regulations.
NOTE
After the neutralization reaction time with ammonia, carry out check
measurements and ventilate. Ventilation until the MAK value is reached:
Formaldehyde concentration <0.3 ppm (Occupational Exposure Limits).