Halma Wagtech Palintest Potatest Go, Руководство пользователя

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19 Use the sterile forceps to remove the
membrane filter from the filtration unit.
20 Starting at the far edge of the petri
dish, use a rolling motion to place the
membrane filter on top of the absorbent
pad. This will prevent air being trapped
between the pad and membrane filter.
21 Replace the petri dish lid and label with
sample number, place, date, time, etc.
to identify in the rack.
22 Place the petri dish into the petri dish rack
and repeat the process for all samples.
Place the filled rack into the incubator for
safe storage ready to start the incubation.
Ensure that the incubator is in the upright
position at all times to avoid leakage of
nutrient broth from petri dishes, paying
particular attention when transporting.
5.1 Resuscitation Period
It is important to note that when the last
sample has been processed, a resuscitation
period of between one and four hours must
be observed before incubation commences.
Environmental exposure can cause coliforms
to become physiologically stressed. The
resuscitation period allows coliforms to
recover before culturing.
With this in mind it is essential to plan
testing throughout the day, particularly if
visiting multiple sample sites. Try to conduct
all sample processing within a three
hour window. This ensures a maximum
resuscitation period of four hours.
The resuscitation period is especially relevant
for water samples where the environmental
exposure is due to chlorination.
The incubator operating software includes the
capacity to have an initial resuscitation period
as part of the standard incubation cycle.
5.2 Incubation Time
Incubate the samples for 18 hours at the
desired temperature. Two preset incubation
profiles are available on the Wagtech Incubator:
• To test for Total Coliforms
incubate at 37ºC for 18 hours
• To test for Thermotolerant Coliforms
incubate at 44ºC for 18 hours
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Sample Processing - Membrane Filtration
Useful to Know
• It is preferable to run the incubator
in-situ in the case
• Ensure the incubator lid is closed
• If powering from the battery only,
ensure the case lid is closed to
minimise power consumption
• Do not place the kit directly on
the floor during incubation
• Do not incubate outdoors during
periods of cold temperature
• Ensure that the petri dish rack is full
during incubation, using empty dishes,
to allow even heat distribution
• After switching on the incubator and
selecting the desired temperature, allow
a few minutes for the set-point to be
reached and for temperature to stabilise.
The incubator will show ‘warming up’
for a period of 30 minutes