By Jeremiah Wann
Any metal fabricator that has been involved in discussions about weld ust and fume management knows about ambient systems. However, a majority of those who work on a shop floor probably don’t have any
idea about how these systems work.
At the most basic level, it is a type of dust and fume collection system (see
Figure 1). Because cartridge collectors are e;icient and have a small footprint, they o;en are recommended for ambient systems. Cartridge collectors
use densely pleated filter cartridges with a very high surface area, so they can
handle a lot of airflow. They are also very e;icient, up to MERV 16, making them
suitable for even very fine fumes. With a cartridge collector, even very small particulate is handled e;iciently.
An ambient dust collection system consistently exchanges all of the air in
the building or a section of the building. On the other end of this spectrum is
a source-capture system, in which all the dust or fume collection is done with
weld arms, fume hoods, or other points of capture.
A metal fabricator installing an ambient system in a shop will enjoy some advantages when compared to more localized approaches to dust and fume management. An ambient system is e;icient. Running enough airflow to keep fumes
moving at several capture points, such as a hood over a welding cell, requires
a large fan and a lot of ductwork and power. An ambient system requires very
little ductwork, so air doesn’t have to be moved through a maze of ducts. Instead, the collector removes dirty air from the entire work area and then returns
it as clean, filtered air (see Figure 2). It’s possible with an ambient system to
create a push/pull operation that pulls dirty air out on one side and blows clean
air back in on the other side. This keeps the overall air in the plant cleaner, since
even fugitive dust or fumes from portable sources are managed.
Why a Modular Ambient System?
A modular ambient dust collection system uses multiple, smaller collectors instead of one large one. This type of system is not suitable for every situation. For
most facilities with consistent production and a large manufacturing space, a
single central system is usually the right choice, as there is only one machine to
maintain and it can run consistently.
Consistency, however, is not the hallmark of most manufacturing environments. A company may have big seasonal fluctuations in production levels, or
a job shop could see manufacturing activity change with the coming and going
In environments where production is variable, two or more small systems instead of one large ambient system may make sense. This allows a manufacturer
to take one of the systems o;line during low-production times while still running the rest of the system. Such an approach can reduce energy costs during
For companies with plans for expansion, a big system for the whole space
might be a big hit to the budget. The option to start with smaller systems and
add on as the company expands may be easier on the budget and help with
planning for the future.
For companies planning to start using their whole space immediately, a single, large system is usually the recommended option. The choice between one
large system and a modular system o;en comes down to the issues of current
and future use of space, along with current and future budgets.
What Does “Push/Pull” Mean in an Ambient System?
When dust and fume collection specialists talk about a “push/pull” system,
they mean that the system pulls dirty, unfiltered air out of the building; runs it
through a dust collector; and pushes clean air back in. This is an e;icient way
of making sure all the air in the area gets exchanged consistently and is always
Why is push/pull better than just pulling the dirty air out? If dirty air is simply
removed and run through the filters, it has to go somewhere. If dirty air is vented
outside, the system is cleaning the air, but the whole process is wasteful. Com-
An overview of
With no ductwork or
localized capture required,
such a system could make
sense for metal fabricators
For some fabricating environments, localized fume and dust collection is not
an attractive option. That’s when it might make sense to install an ambient air system.