Elevators and Fire

47

ELEVATORS AND SPRINKLERS

By Edward A. Donoghue, CPCA

HISTORY

A controversial issue of late has been the
installation of sprinklers in elevator machine
rooms and hoistways. Sprinklers in elevator
machine rooms and hoistways have been recog-
nized by the Safety Code for Elevators and
Escalators, ASME A17.1 since the 1955 edition.
Until recently they were not normally found in
these areas. In the last ten years, building codes
began to recognize sprinklers as one of the most
effective means of controlling fires in buildings.
The building codes at first did not require
buildings to be sprinklered but encouraged their
use by allowing "tradeoffs," which reduced the cost
of construction by relaxing code requirements such
as fire resistance ratings, distances to exits, area
and height limitations, in exchange for full
sprinkler protection. The theory being the cost of
construction would be comparable for a fully
sprinklered building vs. a non-sprinklered building
and the level of fire protection would be equal.
The payoff for a fully sprinklered building would
be in a reduced premium for fire insurance
throughout the life of the building, thus lowering
Operating cost. This has worked and today it is
common for new buildings to be fully sprinklered.
In the last few years, the building codes have gone
one step further requiring fully sprinklered
buildings for certain types of occupancies, such as
high-rise office building, hotels and multiple-family
dwellings.

In the early 1980's, the ASME A17 Safety
Code for Elevators and Escalators Committee
became aware of this trend and initiated a study of
the hazards of water being discharged on elevator
equipment. The possible effects of water on
brakes, shorting of a safety circuit, motor,
generator, or transformer, with the resulting
hazards to people on the elevator is well known in
the elevator industry. Some of the reported
hazards include cars operating with car and/or
hoistway doors opened, loss of brakes and loss of
traction. One well documented accident was from
a leak in a sprinkler system, which resulted in the

elevator brake becoming wet. The wet brake could
Not stop the up traveling elevator. The result was
an out of control up running elevator, which
collided with the machine room floor at the top of
the hoistway at a very high rate of speed. Luckily,
there were no passengers on the elevator car
though the building structure and elevator system
sustained extensive damage. There are numerous
cases of elevators leaving a floor with the doors
open which have been traced back to wet inter-
locks and control circuits. We need only look at a
recent fire in a Chicago skyscraper during which
two firemen, groping their way through a darkened
smoke filled hallway, fell through an open hoistway
door. The ASME A17 Committee could not close
its eyes and blindly prohibit sprinklers in elevator
machine rooms and hoistways. In the real world if
a building code or fire code required sprinklers in
all areas of the building, that code would be
enforced, regardless of any contrary requirement
that would be in the elevator code. At one time
the ASME A17 Committee did approach the build-
ing and fire code community with a proposal that
sprinklers not be required in elevator spaces in
fully sprinkled buildings because of the potential
hazards to elevator users. This was rejected.

The ASME A17 Committee was aware of its
Tesponsibility to ensure that the safety of the
elevator user is taken into account when sprinklers
are installed in areas with elevator equipment. In
early 1982 I, at the request of the ASME A17
Hoistway Committee, made contact with the
National Fire Sprinkler Association (NFSA) then
known as the National Automatic Sprinkler and
Fire Control Association Inc., a trade association
for the sprinkler industry. After reviewing the
potential hazards they made three recommenda-
tions to the ASME A17 Committee.

The ASME A17 Hoistway Subcommittee
reviewed the NFSA recommendations and felt
that one recommendation, for shield and raintight
covers, was impractical. Even if complied with at
the time of installation, shields and raintight covers
would, over a period of time, be removed or
become ineffective, thus permitting the equipment


48

to become wet from a discharged sprinkler.
Verification testing is the cornerstone of elevator
safety assurance; but a waterproof elevator cannot
be operationally tested under the real conditions
for which it is intended. Another recommendation,
for a carbon dioxide or halon system after further
discussion with NFSA, was also discarded as its
ability to provide the required level of protection
was questionable. Non-water automatic fire
suppression systems such as carbon dioxide or
halon must be used in areas with minimal air
movement. Air movement resulting from the stack
effect in the hoistway would make these systems
impractical and ineffective. NFSA third
recommendation to disconnect the main line power
to the elevator before sprinkler activation, was
acceptable, was reworded in performance language,
balloted, approved by the ASME A17 Main
Committee and published as Rule 102.2(c)(4) in
ANSI/ASME A17.1-1984.

ELEVATOR OPERATION
IN A FIRE

If a fire developed in an elevator machine room or
hoistway the sequence of events would most likely
follow this scenario:

(1) Smoke in the elevator machine room or
hoistway during the initial stage of the fire will
activate the smoke detector required by ASME
Rule 211.3, recalling all elevators to the
designated level on firefighters’ Phase I Service.

(2) As the intensity of the fire builds, the
sprinkler system would be activated and the power
to the elevator driving machine would be
interrupted.

It should also be pointed out that the
Committee gave serious consideration to the
possibility of a car stopping with passengers or
even firefighters between floors. All types of
recommendations were reviewed. Most proposals
were along the lines of requiring a heat detector in
the elevator machine room or hoistway to activate
Phase I recall, and when completed then removing
power and allowing sprinkler activation. In
Committee deliberations, we came to the con-
clusion that if there was sufficient heat to activate
the sprinkler, a fire was in progress and there was
no way of assuring control of the elevator except
by disconnecting the main line power supply. A
fire in the hoistway or machine room would in all
probability involve elevator equipment as this is
the only equipment allowed in these spaces. The
ASME A17 Committee also felt that requirements

Elevators and Fire

to delay sprinkler activation was not within its’
scope. Additionally if the temperature is sufficient
to activate a sprinkler, solid state elevator control
systems cannot be relied on to continue to function
as intended. Most modern elevator control systems
cannot be relied on to operate as intended in
temperatures above 100°F. Other papers presented
at this symposium will address that issue in detail.

SYSTEM DESIGNS

Since the publication of ASME A17.1 Rule
102.2(c)(4) many questions have been raised about
what type of system could be installed which would
meet the intent of this requirement. The following
are three methods; the first reportedly the most
economical.

« Rate-of-rise/fixed-temperature heat detectors,
in the elevator machine room and/or hoistway,
would be arranged to automatically disconnect the
main line power supply. These detectors would be
placed near each sprinkler and the sprinkler rating
would exceed the heat detector ratings. The
detectors would be independent of the sprinkler
system. Ina fire the heat detector wouid trip first
and cause a shunt trip circuit breaker to disconnect
the main line power to the affected elevators
before the application of water. This method was
first proposed by a joint task force of NFPA and
ASME A17. The ASME A17 Main Committee
approved Inquiry 86-56, which stated that this
design met the intent of the Code.

« The sprinkler system in the elevator machine
room and the hoistway would be a pre-action
system. A pre-action sprinkler system is a system
employing automatic sprinklers attached to a
piping system containing air that may or may not
be under pressure, with a supplemental fire
detection system installed in the same areas as the
sprinklers. Actuation of a heat detector from a fire
opens a valve which permits water to flow into the
sprinkler piping system and to be discharged from
any sprinkler head which may be open. The heat
detector or flow valve in the sprinkler piping would
cause a shunt trip circuit breaker to disconnect the
main line power to the affected elevators at the
time the valve opens to allow water flow into the
sprinkler piping. The sprinkler system in the
elevator machine room or hoistway should not be
activated by a smoke detector, as this would shut
the elevator down prematurely. A requirement in
ASME A17.1 Rule 102.2(c)(5) prohibits sprinkler
activation in elevator machine rooms and hoistways
by smoke detectors for this very reason. If smoke



Elevators and Fire

detector activation of sprinklers was permitted
there would be no chance for Phase I recail as
described earlier in the scenario of events during a
fire in elevator spaces.

+ The sprinkler system in the machine room or
hoistway would be a dry pipe system. A dry pipe
valve would be installed in the sprinkler piping
where it enters the elevator machine room or
hoistway. The pipe would contain air or nitrogen
under pressure from the sprinkler head to the dry
pipe valve and water to the opposite side of the
dry pipe valve. The heat from a fire would open
the sprinkler head allowing the air to escape and
water to flow into the system. The dry pipe valve
would open and cause a shunt trip circuit breaker
to disconnect the main line power to the affected
elevators. Water flow would have to be timed such
that the elevator would be stopped before water
was discharged from the sprinkler head.

ASME A17.1 AND NFPA NO. 70

A question that has also been raised is whether
there is a discrepancy between the requirements in
ASME A17.1 Rule 102.2(c)(4) and NFPA No. 70
Section 620-51(a) which states in part *...nor shall
circuit breakers be opened automatically by a fire
alarm system." It is the opinion of the Al7
Committee that there is no discrepancy as a
sprinkler system is not a fire alarm system; it is a
fire suppression system. I do not believe it ever
was the intent of NFPA No. 70 to prohibit elevator
operation when a condition hazardous to life and
limb exist.

THE FUTURE

The fire protection community and elevator
industry must balance fire protection and the life
safety of elevator users. A “fine line" must be
drawn to balance two equally important life safety
concerns. We must work together as neither
concern outweighs the other and neither side has
all the answers. Where do we go from here? I
offer the following proposals for consideration:

Elevator Machine rooms

(1) All elevator equipment should be required
to be in a rated fire resistive elevator machine
room. No other building equipment or storage of
non-elevator material should be allowed in elevator
machine rooms. This will limit the fire loading.

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(2) Elevator machine rooms above the roof
should not be required to be sprinklered. The fire
loading in this machine room would be controlled
and any fire in same would not effect the
remainder of the building.

Hoistways

(1) Modern elevator equipment does not
present a serious potential for fires in hoistways.
The hoistway is clean and free of grease and oil
which was frequently found with older equipment.
The car enclosure material is regulated by ASME
Al17.1 and presents minimal fire loading.

(2) The only location where a moderate
potential exist for a fire is the pit, where trash may
accumulate. Sprinklers in hoistways should be
provided in this location only. The sprinkler
discharge should be such that it will not spray the
underside of the car platform. If this was the only
sprinkler head in the hoistway the automatic
disconnect of main line power could be eliminated
if all pit electrical equipment, wiring, limits, etc.
were waterproof.

If the above provisions were enacted the
automatic disconnecting of electric power from
elevators would not be required on the majority of
elevators which are need for fire fighting in high-
rise buildings. Yet, the area’s needing sprinkler
protection would be maintained.

Edward A. Donoghue is president of Edward A.
Donoghue Associates, Inc, Code and Safety
Consultants, Salem, New York. From 1976 to
1989 he was Manager of Codes and Safety for
the National Elevator Industry, Inc. (NEI). He
is Chairman of the ASME Committee on the
Qualification of Elevator Inspectors and in 1986-
87 chaired the Safety Division of ASME. He is a
member of the ASME A17 Elevator and Esca-
lator Main Committee and 11 of its subcom-
mittees, including the Editorial and Code
Coordination Committees which he chairs. Mr
Donoghue is the author of the Handbook —
Al17.1 Safety Code for Elevators and
Escalators. He is a licensed master electrician
and building contractor, certified as a Profes-
sional Code Administrator by the National
Academy of Code administrators, and certified as
an elevator inspector by NAESA, BOCA, and
SBCCI. Mr Donoghue is a member of ASME,
ASTM, BOCA, SBCCI, ICBO, NAEC, NAESA,
NFPA, and the American Arbitration
Association.