units can be made of stainless steel or polypropylene. Specialty vertical flow cabinets are made of
polypropylene for trace metal analysis or for applications in which concentrated acids are used.
Horizontal-flow bench options: Horizontal flow
benches are available in vinyl-clad steel, stainless, or
painted steel with myriad options such as an ultraviolet lights, extra duplex outlets, pressure gages,
removable grills, and safety glass hoods. Horizontal
benches can be installed on existing tabletops or
ordered with stands or base storage cabinets.
Horizontal laminar flow clean benches made
from vinyl-clad steel shell are easy to clean and
maintain and offer the ultimate in a Class 100 (ISO
5) working environment. Made from high-quality
materials and deigned for a sleek appearance, they
resist abrasion, corrosion, stains, and chemicals, as
well as scratches and scuffs.
Biosafety cabinets: Biosafety cabinets are a type
of clean bench designed for both product and personal protection. They are typically used with biological agents. HEPA-filtered air is supplied to the
work space with a slight inflow at the front of the
cabinet. Contamination does not get past the front
grill because a second HEPA filter cleans that air.
Some units require this air be 100 percent exhausted. Exhausting the HEPA-filtered air from biosafety
cabinets is a secondary measure of protection to
ensure no biological agents within the bench enter
the ambient space.
Where to site a clean bench will be dictated by
workflow into, within and out of the clean bench,
and how it will interface with other operations.
Additionally, a clean bench should be located away
from obvious drafts, as well as areas where air
velocity will exceed 100 ft. per minute (the same
airflow velocity coming out of the HEPA filter). If
outside air is blowing directly towards the clean
bench, it will blow into the unit and contaminate
There should be negative pressure around the
HEPA filter and the location of the HEPA filter
should be compatible with future servicing needs.
Any physical restrictions that may affect bringing
the bench into the space such as doors, hallways,
and other equipment should be considered.
Cleanroom benches can be used inside a cleanroom or other clean space. Class 100,000 (ISO 8) or
Class 10,000 (ISO 7) cleanrooms can include clean
benches to create Class 100 (ISO 5) or even Class
10 (ISO 4) areas. With the surrounding space clean,
a clean bench performs better. There is significantly
less particulate contamination for the HEPA filter
to handle and less ambient contamination threatening to infiltrate into the work zone.
UL listing — Local codes typically require UL listing of installed electrical equipment.
Speed control switch — This blower switch will
allow adjusting airflow velocity over time.
Whether you’re considering a clean bench to protect a specific activity in a laboratory, testing and
inspection area, or on the manufacturing floor —
or to supplement an existing cleanroom — clean
benches can be an ideal solution for controlling
particulate in a selected work area. Clean benches
can be specified from a wide range of configurations and options to achieve a cost-effective par-ticulate-controlled environment for any product or
Kevin Weist is President of Clean Air Products.
Your source for up-and-coming products
& companies in clean
CompanyDirectory.................30 ProductsandServices.............40 ProductIndex
2017 Buyer’sGuide Themostcomprehensiveresource ofcontaminationcontrolvendors, productsandservicesavailable.
Stay Ahead in 2017