NFPA Journal - July/August 2018 - 31

prohibited unless the system is dedicated to the exit passageway. Designers
often look at exit passageways as horizontal shafts or as storage areas due
to their increased width, but this is a
point that the fire commissioning agent
can clarify, preventing unnecessary
design changes and saving time and
money in the overall process.

DESIGN PHASE

Consider alternate means for
materials and practices
NFPA 3 defines the design phase as the
period when the basis of design is produced, when drawings and calculations,
including those for design and fabrication, are produced, and when testing
procedures are developed.
It is important to remember that fire
and life safety regulations represent,
in the most general terms, an acceptable level of safety for the locality.
What is required to achieve this level
differ significantly depending on the
locality, and this applies to statutory
design requirements, too. Codes and
standards, including those from NFPA,
are specific on the manufacturing and
performance standards for products
that may not be easily found locally or
where there is little or no experience

with installing the products. Installation experience is often critical to a
system's reliability, performance, and,
in the case of fire and life safety systems, survivability.
Our experiences in Macau have
shown us that it makes operational
sense to accept alternate means
and methods related to products,
equipment, and construction system
components or installation practices
if equivalencies can be proven. It is
best that this issue be addressed early
during the design phase so that all
relevant stakeholders become aware
of the adopted material standards and
listings to give them adequate time to
research acceptable equivalencies to
submit for approval.
Stakeholders should be provided with
the system test methods before they
begin to lay out the systems-though
this can result in additional challenges.
The pace of the Macau projects is
breakneck-the 10.5-million-squarefoot Venetian Macau, for example, was
designed and constructed in three
years, and that was after reclaiming the
building site from a mudflat that was
mostly underwater-and testing of these
alternative materials and methods can
easily be overlooked in the rush to get

GUTTER CREDIT

total calculated building occupant load
exceeding 176,000.
The planning phase provides the first
opportunity to introduce stakeholders
to fundamental challenges such as
horizontal exits and exit passageways
and how they can impact the design of
the mechanical, electrical, and plumbing systems, fire protection systems,
and building operations. Horizontal
exits can impact fire alarm evacuation signaling zones, and sprinkler
zones and smoke zones often need to
be coordinated with the horizontal
exit boundaries. Fire-resistance-rated
boundaries need to have combination
fire and/or smoke dampers, which
require interconnected controls from
associated smoke detectors. Horizontal
exit openings require standpipes on
each side of the wall adjacent to the
opening.
Commissioning can include verifying passive fire protection features,
and exit passageways can present
design challenges that should also be
addressed during the planning phase.
Stakeholders should understand that
they need to treat an exit passageway
as they would a vertical exit enclosure-
meaning that system penetrations
into and through exit passageways are

N F PA . O R G / J O U R N A L * NFPA JOURNAL

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Table of Contents for the Digital Edition of NFPA Journal - July/August 2018
