- This backflow preventer with controllable reduced pressure zone
BA subject to certification to the NF mark
Antipollution is intended for the protection of networks
against backflow of polluted fluids does not
However, there are no microbiological risks
to human health, within the limits of
defined by the Health Authority.
- A BA backflow preventer with a controllable reduced pressure zone
consists of three zones: intermediate upstream
and downstream, each equipped with a
pressure.
- Two independent non-return devices separating
the intermediate zone (reduced pressure zone) of
each of the other two areas, normally closed
in a non-water situation.
- A discharge device (free air) connected to the intermediate zone
normally open when out of water.

- This disconnector is the object of the owner of the installation to be protected, to the sanitary authority:
. a prior declaration of intention to install, two months before the work is carried out
. a declaration of commissioning
. an annual inspection (maintenance), including the ancillary elements that make up the protection package, including
results are reported to the health authority
- If a connection is to be made almost immediately upstream of the backflow preventer, a non-return valve must be provided between
the spigot and the backflow preventer
- Always operate the upstream valve slowly to build up pressure
- Installation requirements :
- the device must be easily accessible,
- it should not be installed in flood-prone areas,
- it must be installed in a ventilated environment (unpolluted atmosphere),
- the drain must be able to accommodate the discharge flow,
- it must be protected against frost or extreme temperatures
Installation: it is mandatory to install :
- upstream of the unit: a shut-off valve and a filter with a flush valve
- downstream of the unit: a shut-off valve
(See technical manual supplied with the device)
Protection at the point of connection to the public drinking water network.