67
Pos
Activity
Action, if required
1
month
3
months
6
months
12
months
24
months
1 Initial hygiene inspection.
Specialised personnel with category A or higher. In
accordance with VDI 6022.
x
2 Check for damages, corrosion and
microbial growth.
Clean and repair.
x
3 Check drain.
Clean.
x
4 Chek condensate tray.
Clean and disinfect.
x
5 Check max. hygrostat sensor.
Function test.
x
6 Check pipes and hoses.
Repair.
x
7 Check control.
Function test.
x
8 Check control valve.
Replace/function test.
x
9 Check for condensate precipitation in
the humidifier chamber.
Adjust nozzle and water volume.
x
10 Check spray nozzles for deposits.
Replace.
x
11 Determine number of CFUs in the
humidifier water.
*if number of CFUs is > 1000/ml, clean, rinse and
dry the tray. Disinfect.
Test supply water quality.
x
* Screening test using dip slides. Use dip slides suitable for determing the total number od CFUs in the water. Further eraching analyses of water samples can only be
carried out by microbiological laboratory, standard valyes listed in the table below
Parameter
Humidifier water
Recooling water
Total number of CFUs
(bacteria) as per ISO 6222
< 1.000 CFU/ml
< 10.000 CFU/ml
Legionella sp.
as per ISO 11731 and ISO 11731-2
< 100 CFU/100 ml
< 1.000 CFU/100 ml
Pseudomonas sp.
King B agar, 36 °C, 48 h
< 100 CFU/100 ml
< 100 CFU/100 ml
Fungi and yeasts
a)
Malt-extract agar, 25 °C, 7 days
< 100 CFU/ml
< 1000 CFU/ml
a)
Higher values, specific to the branch in question, may be found in industrial and production facilities.
8.15
Checklist VDI 6022 - periodic hygiene check for AHU
201218