DEHACO B.V.
Kruisbaak 25, 2165 AJ Lisserbroek (NL)
PO box 189, 2160 AD Lisse (NL)
Tel.:+31(0)252 417 950, fax: +31 (0) 252 418 531
Negative pressure units manual DEH 500
– DEH 30000
2014 v1.0en
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7
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A powerful fan creates a negative pressure, which aspires (polluted) air from
the workspace through a HEPA absolute filter. A pre-filter is applied as well,
which considerably extends the lifespan of the HEPA filter. The pre-filter can
be replaced in the "contaminated area" without having to shut down the unit.
By means of a pressure difference measurement over the filter the degree of
contamination of the filter is indicated. The fan speed is adjustable, which
makes the capacity adjustable, depending on the workspace volume and the
pollution of the filter.
At the backside of the machine return valves have been installed, so in case
of a stoppage of the machine no reverse air current will be created. This
prevents contaminated particles which are loosened by the ‘dirty’ side of the
filter from getting back into the sealed-off zone. The valves also reduce the
risk of extracting "false" air when using one fan. These are important
elements that contribute to the collective safety.
In order to work as efficiently and safely as possible with negative pressure
units, Dehaco also offers advanced tools for monitoring and maintaining