Apportioner Patent Pending
Robert A. Long
Current fire suppression systems categorized as residential 13D, Commercial 13R, and Industrial
13, of the NFPA code allow for fire suppression systems to utilize antifreeze fluid in the piping in attempt to reduce or
eliminate the freezing of the suppression system and its components and the rendering of such system useless. In addition,
fire suppression systems incorporate the use of a backflow preventer, AKA double check assembly, check valve, rpz to name
a few. Fire suppression systems which incorporate antifreeze solutions require the use of such cross connection control devices
for the purpose of risk minimization of the flow of the antifreeze into the drinking water in the event of a failure of public
or private water supply pressure and the back flow of antifreeze into the public or private water supply system.
Essentially, the anti-freeze
is trapped in the fire suppression piping by a series of check valves.Problem: During the activation of the fire suppression system the fire suppression piping is at least partially filled
with an anti-freeze solution including but not limited to glycerin, propylene glycol, ethylene glycol. The public or private
water supply is then opened to the system. The water is on the upstream side of the backflow preventer; the antifreeze solution
is on the downstream side. Initially, the system assumes the static pressure generated by the activation of the water supply.
However, this condition is temporary. Water pressure can increase during time of low municipal use such as at night. This
over pressurization of the anti-freeze solution, and the trapping of such pressure on the system side of the cross connection
control device may cause an undesired result during sprinkler activation. Reference: www.nfpa.org/antifreeze
Additionally, water pressure can decrease during high volume use such as during the day. Anti-freeze
solutions thermally expand and contract due to solar loads and the absence of, daytime outside air temperature, nighttime
outside air temperature and sometimes the effect of inconsistent indoor air temperatures and conditions. Often thermal expansion
tanks are installed to minimize the effects of these conditions. Under these conditions of emanate system instability, the
backflow preventer which contains a first check valve on the inlet, a second check valve on the outlet, and (on an rpz or
high hazard device) a relief, or dump valve in the center. If the water pressure is reduced below the initial
activation pressure, the antifreeze in the downstream piping will remain the same as the initial activation pressure as it
cannot escape into the municipal water source due to the proper operation of the check valves in the backflow preventer. Primarily,
the second or downstream check valve holds the antifreeze at initial pressure.
is that this pressure differential between the reduced inlet water and the initial anti-freeze pressure places strain on the
second check valve consequently causing pre-mature failure of the seals that allow for proper operation of the second check
valve. The rubber seal may become cut by the seating surface. This may allow for some anti-freeze solution to flow backwards
into the backflow preventer/rpz which consequently is dumped through the backflow preventer/rpz either to the floor or the
building drain. The system is then re-pressurized when the municipal water supply restores its pressure allowing water to
flow through the backflow preventer and into the anti-freeze side of the fire suppression system. After several days of this
“Washing” condition, the anti-freeze side of the fire suppression system becomes increasingly diluted furthermore,
compromising the anti-freeze solution can become frozen not only rendering the fire suppression system ineffective, but can
freeze to such a degree that the system components become fatally compromised and often ruptured to the point where both anti-freeze
and water are dumped from the compromised system causing water damage, flooding, environmental impacts, and often pieces of
the compromised components will enter the fire suppression piping mandating a full replacement of system piping and components.This condition exists whenever two dissimilar substances are utilized in a fire suppression
system where check valve type devices attempt to separate the two dissimilar substances preventing cross connection.
Apportioner’s job in closed position is to provide a physical separation between the dissimilar substances and open
automatically during a fire. Additionally, it is the Apportioner’s job to maintain antifreeze solutions at a low pressure
so as not to compromise the effectiveness of the antifreeze solution during sprinkler activation. Additionally, it is the
job of the apportioner to protect the cross connection control device from damage resulting in pressure spikes of the
inlet. The Apportioner is a trade name of The ECO Group Inc. and is essentially the eco dry pipe assembly
branded under the name “Apportioner. It is a valve, not limited to ball, wafer, lug, plug, gate, which is actuated by
a pressure actuator which contains a spring open feature and a pressure to close feature. It is a non-differential device.
It is also considered a fail open device.
The unit itself requires no external power source for activation, and
no compressor. The unit incorporates a limit switch with a post indicator to show valve position. The unit
shall be installed upstream of the backflow preventer as close to the backflow preventer as possible. The actuator pilot tube
shall be connected to the system side downstrean of the cross connection control device. The inlet side of the Apportioner
is in contact with a type of suppression substance i.e. water. The outlet side of the Apportioner is in contact with the fire
suppression system.When the fire suppression system is readied via. opening of the inlet control valve, the municipal water
pressure provides energy to close the Apportioner via. pressurization of the system downstream of the Apportioner and
the backflow device. This pressure is typically, but not limited to 25 psi. The fire suppression system substance, typically
anti-freeze but not limited to, when pressurized during start up, will provide pressure to the Apportioner’s actuator
which will overcome the actuators spring tension consequently closing the valve, approx. 25 psi, providing
a physical separation between the dissimilar substances thus limiting the system side pressure to 25 psi. In this closed position,
the Apportioner protects critical components from negative effects of over pressurization and excessive back pressure. In it's
readied position, the limit switches within the Apportioner act as notifiers in the event of pressure loss as a result
of system leakage. In the event system pressure falls below opening set point, the Apportioner will simply slowly open,
allowing for stabilization of the system pressure and closure of the Apportioner. If pressure decreases, the
same sequence will occurr sending repeated trouble alerts. In the event of a fire, a sprinkler will open as
designed, antifreeze pressure is dissipated through the sprinkler, the Apportioner valve opens, and the water is free to flow
through the system as designed. It is noted that substances do not have to be dissimilar in nature.
The Apportioner should
be installed where field conditions are such that pressure or backpressure conditions exist and need to be controlled.
will maintain and monitor “A Portion” of the system separate from “A Portion” of the system. In addition to the action of the Apportioner, its’ limit switch will allow for onsite
and offsite monitoring of the fire suppression system pressure via. alarm signals, and the transmitting of information for
the purpose of, but not limited to leak detection of expensive, often hazardous suppression fluids. This leak detection will
allow for proper response and complete awareness as to the condition of the substance at all times. The Apportioner provides
the fire alarm signal.The Apportioner is intended to protect
cross connection control devices and other system components from failure due to the existence of system pressure differentials.
Additionally high system pressures which may cause antifreeze solutions to become compromised.The Apportioner will prevent the municipal or supply side water pressure to push into the suppression