Rev.
00
GW2045 – GW1060 Manual
Pag. 22 di 43
6.3. WASHING
PROGRAMME
SETTINGS
Consult the following table to select the required programme. It gives the washing cycle most able to suit the
nature of the instruments you need to wash and the degree of dirt involved.
Once you have found the most suitable washing programme, turn the PROGRAMME SELECTOR (1) knob
and select the desired programme by setting it to the relative reference number.
PR-1: Pre-wash
, Quick washing programme using cold water (soaking glassware while awaiting wash).
PR-2: Washing programme at 60°C
suitable for plastic ware.
PR-3: Washing programme at 80°C
suitable for plastic ware.
PR-4: W thermo-disinfection at 90°C
for 3’ (A0 =1800).
PR-5: W thermo-disinfection at 93°C
for 10’ (A0 =12000).
PR-6: CUSTOM 1
, personalised programme set by authorised SMEG technicians on customer’s request
(default: the programme carries out wash + thermo-disinfection at 93° for 3’).
PR-7: CUSTOM 2
, personalised programme set by authorised SMEG technicians on customer’s request
(default: the programme carries out wash + thermo-disinfection at 93° for 10’, with prewash).
PR-8: Service Programme
, start up to test the detergent and neutralizer dispensers (carry out on first start-
up).
6.4. THERMAL
DISINFECTION
IN
ACCORDANCE
WITH
THE
PARAMETER
"A0"
The concept of
A
0
(introdotto dalla EN 15883
4
) is used to understand the meaning of the temperature and
time values shown in the programmes including thermal disinfection.
The value of Ao expresses the degree of “lethality”, released by the thermal-disinfection process, in terms
equivalent to seconds at a temperature of 80°C, wit h reference to micro-organisms that possess a value z
equal to 10 (the value z means the variation in Kelvin degrees - K- required to obtain a variation of ten times
the microbial inactivation of a disinfection process). The
A
0
value that must be obtained depends on both the
type and number of microorganisms on the contaminated medical device and on its successive use.
According to EN ISO 15883 and the recommendations of the Robert Koch Institute (European authority on
the subject), an
A
0
of 600 is considered as the minimum standard for non-critical medical devices, i.e. for
those that only come into contact with uninjured skin. A further condition required is that microbic
contamination must only be slight and there must be no heat-resistant pathogens present. An
A
0
value of
600 can be obtained by maintaining a temperature of 80°C for 10 minutes or 90°C for 1 minute.
If instruments are contaminated with heat-resistant viruses, such as those of hepatitis B, the value of
A
0
must be at least 3000. This can be obtained by maintaining a temperature of 90°C for 5 minutes.
An
A
0
value of 3000 is considered the minimum value to apply to all medical devices considered to be
critical.
Programmes that include thermal disinfection have therefore been designed to offer the following
A
0
values:
Temperature – time
A
0
90°C 1’
600
90°C 5’
3000
93°C 5’
6000
93°C 10’
12000
The approximated formula to calculate
A
0
is given as follows: where:
−
•
=
10
80
0
10
T
A
τ
τ
= holding time in seconds at the disinfection temperature.
T
= disinfection temperature in Celsius degrees.
If the temperature is 80°C, A
0
is the same as the maintenance temperature.
4
NORMA EUROPEA UNI EN 15883 "Apparecchi di lavaggio e disinfezione", in particolare di riferimento è la parte 1 della norma,
15883-1 nel paragrafo 3 relativo alle definizioni,
Terms and definitions
, e nell'allegato B,
A
0
concept
.