2. Please note:
2.1
Safety
All work should be undertaken in compliance with national accident prevention regulations. A second
person is required for safety reasons, particularly when inspecting tanks.
In addition, the applicable national regulations and standards must be respected during installation, as-
sembly, maintenance, repairs etc.
The entire system must always be switched off and secured against unauthorised resetting during any
work on the system or system components.
The tank cover must always be kept closed, except during work inside the tank, otherwise the risk of ac-
cidents is high. Only original GRAF covers, or covers approved by GRAF in writing, are to be used.
GRAF provides an extensive range of accessories, which are all coordinated and can be combined to
form complete systems. The use of accessories that have not been approved by GRAF results in the ex-
clusion of the warranty/guarantee.
2.2
Ventilation
All tanks must be ventilated. Additional ventilation ducts or openings are to be arranged if required. If this
occurs, the ventilation ducts should be arranged so that natural ventilation is possible (chimney effect).
Ventilation with unobstructed outflow
2. Please note:
Ventilation in the case of infiltration or with obstructed
outflow
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