CEAC-2022-05-May

News
Fast, Reliable Smoke Detection for the
Dustiest Settings
Early smoke detection is often critical to quickly suppress
fires. In some settings, such as manufacturing facilities,
voluminous dust and particulates from various products and
processes can be confused with smoke by most traditional —
or passive — smoke detection systems, triggering ongoing
alarms. Resolving these alarms often requires excessive troubleshooting
and maintenance to keep the system functional.
When this is the case, prevalent nuisance alarms may compromise
safety.
Although most manufacturing facilities deal with some level
of dust, there is no more challenging environment that
illustrates the need for advanced detection systems that
accurately distinguish dust from smoke than inside a dust
collection system. Fortunately, even within this dustiest of
environments, aspirating smoke detection (ASD) technology
can be an effective option.
According to Khaleel Rehman, director of development for
Honeywell’s advanced detection fire team, advanced ASD systems
can significantly reduce false alarms and maintenance
while increasing safety by detecting smoke at the earliest
possible stage via numerous sampling points. The process
draws in air through durable piping and analyzes it using
sophisticated laser-based technology, imaging, and photodiode
technology. Continuous air sampling drawn from the
protected area through the pipe network to the sensing unit
provides the fastest possible smoke detection rates. In doing
so, the system effectively distinguishes between actual smoke
and dust or particulates to all but eliminate nuisance alarms.
This core technology has been used for decades in sensitive
applications such as cleanrooms and data centers where early
smoke detection is critical.
Although these systems are quite flexible, many facilities use
different processes and materials in varying volumes with
unique facility layouts. It is important to consider engaging
a partner that can design the system to fit a facility’s specific
needs.
Aspirating Smoke Detection (ASD) systems like those produced by Honeywell
are designed for reliability, and are capable of customization to
minimize false alarms and maintenance, while increasing safety.
The zinc dust accumulates quickly and abundantly inside the
ducting, and can easily overwhelm the filters. This required
excessive inspection and frequent maintenance to keep the
system fully operational, according to Mike Angstadt, president
of Palmetto, Florida-based Flagship Fire, Inc., whose
company was hired to improve the system’s fire safety. The
company provides special hazards fire suppression, control
and detection solutions for unique, high-value industrial
assets.
Joseph Albert, project manager at Flagship Fire, Inc. notes,
“When technicians would do routine maintenance every few
months on sections of ducting, they would bang the sections
with a rubber mallet to remove several inches of zinc dust
that accumulated inside of this duct work.”
According to Angstadt, the dust laden, paper-based filter
media would also periodically catch fire when ignited by a
stray spark. The plant tasked Flagship Fire to improve smoke
Extreme Dust: A Smoke Detection and Maintenance
Challenge
In a manufacturing process at an aluminum tubing provider,
a fine, hot zinc powder is spray-coated onto tubing in a spray
booth area. The excess powder is then directed to a dust
collection system consisting of large-diameter ducting and
paper-based filter media before clean air is vented outdoors.
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| Chief Engineer