There are many filter types to choose from and
it’s imperative to review each manufacturer’s
guide of retained chemicals or chemical listings.
It’s also important to make sure that the chemicals used are retained by the filter under the
various conditions set by AFNOR NFX 15-211
standard. Filters have a “lifetime”, so filter saturation detection methods need to be provided
by the manufacturer.
The filters need to be changed once saturation has been approached or reached. This
maintenance effort is straightforward, handled
within the operator work zone and requires
minimal training. The cost for replacement
filters and the disposal of used filters is usually
more than offset by the energy saved by not
requiring additional costly make-up air. Typical
energy savings are two to three times the total
filter replacement costs.
Finally, since no advanced planning is
required, ductless fume enclosures are immediately available for use—without the necessity
of having excessive installation costs. Mobility
is inherent with this design as only electrical
power and bench top space are required to relocate the ductless hood.
Filtered fume hoods can replace many conventional ducted fume hoods, while ductless
fume hoods remain as a limited-application
product. The sustainability of both filtered and
ductless fume hoods is very high, as no additional make-up air is required. The safety of
filtered fume hoods is enhanced by automatic
As an essential part of user safety, responsible
manufacturers should offer assessments and
precautions for anyone contemplating the use
of filtered or ductless fume hoods. These assessments should include independent third-party
testing, comprehensive chemicals lists—those
approved and not approved—and individual
application review for safety and financial
viability. Only then can a recommendation be
made for the selection of the most appropriate
unit. After installation, there should be a program in place to constantly monitor the unit
for the user so that they can focus on their work
and not the fume hood.
— Kenneth Crooks
Director, GreenFumeHood Technology
Filtered fume hoods
A filtered fume hood provides the benefits of
both ducted and ductless fume hoods in one
unit, along with the ability to provide safety
and sustainability. The filtration, detection and
communication technology in a filtered fume
hood allows it to be safely used in a broader
range of applications typically served by ducted
fume hoods. Filtered fume hoods use advanced
filtration media that is capable of capturing a
wider range of acids, solvents and bases simultaneously. This enhanced filtration enables the use
of one filter type for all applications, simplifying
selection and replacement.
In addition, filtered fume hoods use enhanced
sensing technology for detection of chemical
breakthrough of the primary filter. This automatic filter saturation detection, and all other operating parameters and safety alarms, can be communicated to EH&S and facilities departments via
Ethernet, BACnet or other communication protocols. Meanwhile, as detailed in AFNOR NFX
15-211 standard, Class 1 filtered fume hoods have
a second layer of filtration offering a safety reserve
for use when the primary filter is saturated and a
replacement filter is being scheduled.
Mixed Signal Oscilloscopes
new product from RIGOL!
Compare & Save
vs TEK MSO3000 series!
• 100-500 MHz models
• 16 digital and 2 or 4 analog channels
• Deep memory - 140Mpts in analog channels and 28Mpts
in each digital channel max.
• Fast sampling rate - 4 GSa/s analog and 1 GSa/s digital max.
• 100,000 wfms/s max. waveform capture rate
To check out the Best Value in Scopes,
call 877-4-RIGOL-1 or visit RigolScope.com