THE UPS AND DOWNS OF PARKING LOT CONTROL ARMS
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By Michael Panish, Door & Gate Expert Witness
THE UPS AND DOWNS OF PARKING LOT CONTROL ARMS - What every attorney needs
to know about how they function, why they fail, and why someone was injured.
Who is at fault, who is to blame, and what the industry standards are
that affect the claim?
By Michael Panish
My office is contacted many times a month regarding a parking lot control
arm or barrier gate injury of some sort. These terms are generally interchangeable;
however, some standards do not use the term control arm, only barrier
arm. Usually, the attorney starts by explaining that the plaintiff was
hit by a descending parking lot arm without any advance warning. Sometimes
the injured party is riding a motorcycle, sometimes walking as a pedestrian
under the control arm. In other claims the gate control arm does not fully
cycle open before returning to the horizontal position. There are also
cases where the gate appears to have been left in an open position, turned
off, and is remaining in the upright position for extended periods of
time and suddenly descends just as a pedestrian begins to pass under it.
There are numerous variations of the same type of accident, but there
are big differences in who the responsible party is for the cause of injury.
Some of the first questions asked pertain to how the device works, and
why the control arm did not detect the person as they walked through the driveway.
FULLY AUTOMATED OR ATTENDED, BOTH SHARE SOME CHARACTERISTICS
Manufacturers of most control arm gates build their devices to activate
in one of two different ways. Fully automated by remote stimulus and/or
manually controlled by a parking lot attendant.
Many parking lot control arms are activated when a driver pulls up to a
parking lot gate in a vehicle. As the vehicle arrives, an electronic signal
is sent to the parking control arm mechanism due to the detection of that
vehicles large metallic presence interacting with an in-ground magnetic
in- ground magnetic field is created from buried wires known in the trade
as an induction loop. The signal generated from this “activation
or approach magnetic induction flux loop” often is connected to
a ticket printing device. This piece of equipment is commonly referred
to as a “Ticket Spitter”. The “Spitter” issues
a ticket, usually for single vehicle access prior to activating the control
arm gate mechanism causing the arm to raise. An alternative method to
get the control arm raised requires a driver to reach out of the car and
push a button to receive a parking lot access ticket from the “Spitter”.
(In that mode of operation, it is probable that there is no magnetic loop
in place.) In either case, once the ticket is taken by the driver, the
“Spitter” sends a control signal to the gate arm mechanism,
and the arm is supposed to raise, generally for a single vehicle to control
access to the parking lot.
As the vehicle transitions from the approach location where the ticket
is issued, once the control arm raises, there is usually a functioning
magnetic flux or induction “Safety Loop” located under the
control arm swing location which provides protection for a vehicle until
it has cleared the “Zone of Danger” underneath the active
control arm. The control arm may also be kept in the open position by
a timer that holds the gate arm up for a predetermined time prior to closing.
Using a timer function in place of an in-ground magnetic loop is risky,
as vehicles may not clear the opening, or another vehicle can attempt
to gain access without receiving a usage ticket. Older, non-current standard
compliant installations have been seen without any consistency of design
or operational function.
There are multiple installation variables that can alter the basic loop
positions and quantities, but most basic systems operate as described
above using at least two control loops. One underneath the control arm,
and one egress or approach loop. In some installations, all three loops
will be present. This triple looped system offers the most comprehensive
safety for a vehicle, NOT A PEDESTRIAN!
MANUAL VERSIONS OF PARKING LOT CONTROL ARMS
A parking lot attendant, usually positioned inside an adjacent booth, has
a control switch that activates the parking lot control arm. The attendant
has a switch that raises the arm, lowers the arm, and keeps the arm inactive,
either up or down. Some manually controlled arms also have magnetic induction
loops connected to the parking lot control arm when the parking lot is
unmanned after hours, in which case, the arm should function in the fully
automatic mode, as described above.
CONTROL ARMS ARE WEIGHT ACTIVATED, RIGHT?
Contrary to popular belief, most parking lot control arms are activated
due to a change in a magnetic field which is generated by twisted energized
wires positioned below the adjacent pavement of the control arm. Modern
control arms are not usually controlled by pneumatic pressure like an
old-fashioned gas station bell hose. It is unlikely that the weight of
a vehicle or a pedestrian walking underneath the arm will stop an active
control arm. Modern parking control arms are triggered by a change in
the magnetic induction loop return. Modern induction loops are manufactured
from a relatively light gauge of wire, placed in a rectangular shape that
is calibrated and sized to detect a change in the magnetic field when
a metallic object such as a vehicle enters or covers that field.
Many attorneys insist to me during their initial call that a pedestrian
walked next to a control arm, activated the arm due to their client’s
weight, and the arm failed to remain open as they walked under the arm.
This scenario is generally incorrect. Weight of a vehicle, or weight of
a pedestrian cannot activate most modern parking control arms. A trigger
of a control arm or activation of a street traffic light due to weight
has not been in practice for many years. It is highly unlikely that a
pressure pad sensitive to weight is ever controlling a parking lot arm today.
UL 325/ASTM F2200
There are several standards that are used to design and install parking
control/barrier arm devices. In the most basic sense, UL 325 (Underwriters
Laboratories) in conjunction with ASTM F2200 (American Society of Testing
Materials) as well as other trade organizations have compiled standards
that are designed to make a control/barrier arm installation safe and
user friendly. Most of the regulations that are referenced in these standards
have been adopted and in common trade practice and usage since the year
2000. There are numerous revisions of these standards, and industry best
practices for service providers and installers should be to bring any
of these past installed products up to date with the latest revision of
the standards for entrapment and function.
A UL 325 COMPLIANT INSTALLATION
A UL 325 compliant barrier arm or parking control arm installation requires
several conditions to be met. The parking control arm mechanism is generally
installed atop a concrete island (not a UL requirement). All conduits
and control circuits are routed into the base of the control arm mechanism
through this elevated platform. This is not always the observed situation;
however, it seems to be the most encountered condition as the elevated
platform provides protection from vehicle impact for the control arm housing.
When this island is placed by a concrete contractor, it is the perfect
time for the facility to install a dedicated pedestrian walkway.
This dedicated pedestrian walkway must be away from the “danger zone”
of the active control arm. This dedicated pathway is one of the most important
factors to having a UL 325 compliant installation. Another significant
safety device required for a UL 325 compliant installation is blatant
painted warnings on the pavement located adjacent to both sides (ingress
and egress) of the control arm. For instance: “Not a Pedestrian
Walkway” or “Motor Vehicles Only” along with bright
stripes and designs to draw the attention of a pedestrian to indicate
danger prior to coming into the “danger zone”. Signage is
also required, on the control arm itself, the cabinet that houses the
activation equipment, and on a placard in front of the control arm equipment.
PEDESTRIAN SIGNAGE, NOT ALWAYS EFFECTIVE
I have observed for many years that pedestrians are often walking while
distracted by their cell phones, other people they are engaged in conversation
with, or low lighting conditions. Although a UL requirement for a compliant
installation is having a warning sign placed in several areas adjacent
to and attached to the control arm, that warning is often unseen for many
reasons. Pedestrians often look to the location that they are planning
to reach without seeing their immediate surroundings. When this occurs,
any warning signage has no value to them. A control arm sign that is attached
to a vertically elevated arm is out of the field of view for a pedestrian
in most cases so that warning label is ineffective. A distracted pedestrian
is as likely to walk off a curb in front of oncoming traffic or walk under
a raised parking control arm without realizing that the danger exists.
Blatant pavement signage has also been ignored by distracted pedestrians
focused on getting to where they want to go.
WHO IS AT FAULT?
There are a variety of cases where a parking lot control arm has malfunctioned
due to a complete lack of maintenance awareness. Most manufacturers suggest
parking lot control arms should be inspected and evaluated for function
by a professional service provider at least once a year. This interval
inspection routine is questionable in a parking area with high usage of
the control arm. In a case of continual usage, a professional service
provider should be in place to inspect the device every quarter. Usually,
some malfunction occurs to a control arm function that requires professional
visits more frequently than every 3 or 4 months in a high usage installation.
Sometimes property management or an owner employs a maintenance person
to make repairs. This can be problematic, as that maintenance person may
not have adequate skills or training as to how to properly inspect the
functions of the control arm mechanism and related systems correctly.
In other low usage areas, where the arm is either occasionally used, unused
and left in an open condition, or there is minimal parking lot activity,
property owners never get their control arms serviced. They are unaware
of the need for service, feel that the arm is operating correctly when
it is used, or just do not want to expense the services of a professional
due to budgetary constraints or an ignorance of how the device functions.
Most owners of parking control lot arms do not understand or have the skills
to properly check all functions of the arm control mechanism. They may
be capable of replacing a broken arm component when damaged by a vehicle,
but rarely understand the actual control arm electronic requirements.
When a competent, qualified professional service provider is used to make
proactive inspections of a parking control arm, there are numerous tests
and electronic evaluations that are made with dedicated service equipment
that the average control arm owner would not possess.
One of the most basic critical evaluations to ensure that a parking control
arm is properly functioning involves checking the resistance capacity
of the in-ground magnetic flux loops. These loops are one of the primary
controls for avoiding vehicular/arm impact collisions. There is an electronic
meter known as a “megohm meter” or “meggar” that
checks the condition of the in-ground loop insulation material of all
system loops. It measures millions of ohms of resistance by placing a
signal onto the flux loop when tested. The unbroken condition of the insulation
that is the outside coating of these in ground wires is essential to have
a properly functioning flux loop.
Electrical leakage to the surrounding ground due to partial loss of the
protective insulation creates false imaging to the controls of the parking
arm equipment. The insulation of these flux wire loops has an expected
life. This is due to corrosive aspects of the material that the wires
are encased in. Concrete, asphalt, various cement, sands and gravel all
have corrosive components to their chemical composition. These acids can
affect the lifetime of the flux wire insulation. Depending upon how much
water leaches through the pavement, these flux wires will eventually be
exposed to chemicals that will break down the insulation protection that
is required. When that insulation breakdown finally happens, the operation
of the magnetic flux loop is inconsistent and often becomes a danger to
vehicles of all kinds (cars, trucks, motorcycles, bicycles, trailers,
etc.) using the control arm.
Defective operation of parking lot control systems has been frequently
observed following flooding due to driven rains or adjacent sprinkler
systems. In several past cases, service providers and owners that failed
to take critical tests to determine insulation quality of magnetic loops
have been responsible for damage caused as a result of those unknown wire
conditions. In some claims, the service provider was aware that the loops
were not functioning up to specifications of the loop manufacturer yet
failed to take any proactive action to have them replaced, or minimally
alert the owner of the arm that the condition existed. To save money,
some service providers fabricate their own loops for these installations.
When that is the case, the service provider needs to regularly verify
the condition of the loops to make certain that the performance is as required.
ADDING ADDITIONAL SAFETY FEATURES
It is usually a goal to make a product that is as safe as is possible for
all users. The UL 325 standards attempt to keep current with technological
advances but are not always up to date. Basic requirements as described
above do make control arms reasonably safe, but there are additional safety
devices that can be added to most parking control systems.
Cross threshold optical sensor beams. These beams function in the same way that a common residential automatic
garage door bottom beam sensor works. They provide an additional protection
to both vehicles and pedestrians as they stop the control arm from descending
when the beam is obstructed. To be effective, they need to be properly
positioned and in enough quantity.
Audible alarms are being installed to alert pedestrians and drivers in proximity to the
control arm that it is about to descend.
Visible alarms that provide strobe or flashing light action alert pedestrians and drivers
that the control arm is about to descend.
Contact safety switches attached to the bottom edge of a parking control arm cause the descending
arm to reverse when 10 pounds of force from an obstruction occurs.
These added safety devices are not part of any standard requirement but
are relatively inexpensive to add to a control arm system and tend to
be more effective in warning pedestrians that something is about to happen.
Both alarms begin working a few seconds before any activation movement
of the control arm starts. A properly positioned beam or beams can be
effective in stopping the descent of a control arm when a pedestrian is
obstructing the beam but is not fully reliable due to user interactions.
It is best practice to avoid having any pedestrian walk under the pathway
of a control arm.
THE IMPORTANCE OF KNOWING THE ACTIVE CONDITION OF ALL MAGNETIC LOOPS
Many motorcycle injuries from parking control arms have occurred as a direct
result of magnetic loop degeneration. Properly operating control loops
should have enough sensitivity to “notice” most metallic objects.
I have been able to test magnetic fields for gates and control arms using
a one-foot square piece of sheet steel with positive results that have
activated the devices. Cars and trucks obviously have larger footprints
than a motorcycle, scooter or bicycle, but if the loops are sensitive
enough and the module that controls those loops is properly adjusted,
it is not unreasonable to get a big enough change in the magnetic field
to trigger the operator mechanism. Unless there are specific access and
egress points for motorcycles and other two wheeled conveyances, most
riders will expect that a control arm will react to their rides. It is
critically important to have competent professional service providers
evaluate control arm systems on a regular basis. Changes to sensitivity
of the magnetic fields that can occur suddenly create problems resulting
in cosmetic damage to cars but can cause catastrophic dangerous conditions
for two wheeled vehicles. Motorcycle accidents with control arms are particularly
dangerous when the safety loops that are positioned under the control
arm fail or work intermittently. A rider will gain access, the control
arm will lift, and without warning the control arm will descend into the
face or on top of the head of the rider leading to potentially severe
injuries. It is a reasonable expectation on the part of a motorcycle operator
that the arm will remain open and the in-ground loops will detect the
presence of a motorcycle. Dangerous conditions that exist as a result
of deferred or non-existent maintenance of parking control arms have created
many motorcycle rider impact injury claims.
VARIETY OF OBLIGATIONS ON ALL PARTIES
THE OWNERS OBLIGATIONS
When there is no proactive maintenance of any device or piece of equipment
in a facility the owner is negligent for failing to make the effort to
ensure that the property will be safe for all invitees. Failing to employ
competent professional service providers due to cost, ignorance, laziness
or stupidity is negligent. Having properly maintained and properly operating
equipment is responsible and meets the standard of care expected of an
owner that invites the public on to the property. Having a proactive plan
to provide inspections and maintenance of all equipment is responsible
and diligent. If the professional service provider has not met the standard
of care, the owner may ultimately have the responsibility for the defective
condition of the control arm. Whether or not there is an indemnification
policy between the service provider and owner can determine who is financially
responsible for the injury claim. If the owner has been informed of operational
or functional deficiencies by others and has refused to upgrade or make
the control arm standard compliant, it is more probable than not that
the owner will become a responsible party.
A SERVICE PROVIDERS OBLIGATIONS
If a professional service provider does not make the property owner aware
of changes in standards or advise the owner of possible safety upgrades,
that professional is not acting up to industry expectations. The service
provider is also not taking the opportunity for increased sales revenues
derived from making those suggestions. If a service provider has offered
limited services to an owner (such as an on-call / as-needed basis), it
is hard to place the blame on the service provider that was just providing
specific work. It is still recommended that all deficiencies in an operating
control arm system be identified, specified, and described so that the
service provider can transfer the liability onto the owner of the now
non-compliant control arm.
When a professional service provider installs a parking control arm in
a non-compliant installation (for example there is no dedicated walkway
or signage), the obligations for that deficiency depend upon the communication
and working relationship with the owner of the property. There are several
different scenarios that determine the responsible parties for the non-compliant
- Was the service provider only called upon to install a specific product?
- Was the service provider limited by the owner of the property to only do
a specified job?
- Did the service provider make the owner aware of the deficiencies of the
installation prior to, during or after the work was performed?
- Did the service provider attempt to make the installation current standard
compliant, but was told not to?
- What portion of the installation was the service provider involved with?
For example, the service provider was contracted by a general contractor
and told to specifically provide a portion of the products required to
make the installation compliant. The representations made by the general
contractor was that the general would place all signs when the project
was turned over to the owner, the general would have appropriate pavement
warnings painted and placed when the paving was completed, and the general
would install a dedicated walk way for pedestrians at a later date.
If the service provider acted in a trade appropriate manner, fulfilled
all duties and obligations informing the owner or management of the non-compliant
conditions encountered, that service provider has met the industry standard
of care. In that case, the service provider is not responsible for a non-
compliant control arm installation.
PEDESTRIANS INVOLVED IN A PARKING CONTROL ARM INJURY
WHAT WERE THE CIRCUMSTANCES?
This condition has been seen so many times that multiple injuries were
caused in the exact same way. In several past claims, a pedestrian was
essentially forced to walk under a parking control arm because there was
no other way to exit the lot or garage space. There was no dedicated pedestrian
walkway, no openings in a fence, no indicated paths for people to exit,
no special stairways or other means of egress, and in those cases, the
control arm was unavoidable. In other claims, a remotely operated control
arm, that was activated by a guard in an adjacent hut came down upon several
pedestrians due to the guard being careless. The gate was routinely in
an upright position, the guard never meant to have the gate close upon
the pedestrians, yet the injury took place as a direct result of the guard’s
ACTUAL CASES OF PEDESTRIANS BEING STRUCK BY PARKING CONTROL ARMS
A group of pedestrians walking into a concert venue walked under a control
arm, which came down just as they walked under it. There was plenty of
space on either side of the control arm, but there was no signage or painted
warnings on the pavement showing where the arm could come down.
A pedestrian going to work in a hospital, caused her own injury. She watched
as a car went through the control arm entry point and did not realize
that the gate would close upon her. In her deposition statements she said
she thought that the arm would stay up because she had seen other people
walk through the same opening in the past without the arm descending.
There was a dedicated walkway a few feet away from where this incident
occurred, going through the vehicle path was a shortcut that saved a few
steps and caused her major injury.
Tenant of an apartment complex gets hit with control arm gate after helping
a neighbor gain access when the neighbor had forgotten her card key access
pass. The injured party stood adjacent to the control arm, swiped her
access card, watched her friend drive through the opening and then without
thought proceeded into the lot following the car. Once the car cleared
the magnetic loops, the arm descended as designed, only it struck the
tenant, knocking her out only seconds after her good deed.
INTENDED USE OF CONTROL ARMS
Control arms are designed for restricting the flow of vehicles into or
out of a location that desires regulation of traffic. The equipment functions
based upon activation signals received as described above. Access points
that have control arms are not intended for pedestrian traffic at any
time. While most vehicles are metallic, most pedestrians are non-metallic.
The machines that operate these control arms are dumb robots without any
capabilities of intervention in the event of a non- conforming use. A
pedestrian attempting to walk through a parking control arm location is
a non- conforming use, and there must be some common sense exercised when
assessing an interaction with any robotic machine.
PROPERTY OWNER OR PROPERTY MANAGER RESPONSIBILITIES
All owners that have public, commercial, or residential community properties
can expect usage by thousands of different people. If proactive maintenance
and evaluation of the location setting as well as the condition of the
equipment that people interact with is made routinely, an owner can take
the needed steps to keep the property in a reasonably safe condition.
An owner should enlist the services of qualified and competent service
providers to make certain that all access control arms are properly functioning,
and the site is totally compliant. If an owner takes responsibility and
hires professional service providers to make a property fully compliant,
that owner has met his obligations to all invitees of the property. Failing
to proactively evaluate a potentially dangerous condition is negligent.
Maintenance saves money in the long run. Keeping equipment of all kinds
in good condition is responsible and indicates good ownership. Safety
to all invitees should be of prime importance to a concerned owner.
TERMS YOU SHOULD KNOW
Magnetic induction flux loop: A wire of specific size and design placed below the pavement surface to
create a magnetic field which is altered when a metal object (vehicle)
is in proximity or on top of the wire field.
Ticket Spitter: A printing device used to dispense parking tickets to patrons of a parking
lot. Manual (push button by user) or automatic (triggered by presence
of vehicle on top of magnetic loop in ground), records date and time of
entry onto a paper ticket and then when removed from the slot activates
a control arm mechanism to gain access into the lot.
Control arm device: All electronic and mechanical equipment combined to allow a gate arm to
raise and lower.
Approach loop: Magnetic loop placed in ground to trigger activation of a control device.
Safety Loop: Magnetic loop placed directly under the path of a parking control arm
to protect vehicles from impact by a descending gate arm when the zone
is occupied by a vehicle.
Egress loop: Magnetic loop placed in ground to hold a control device in the open position
until the area can be cleared. Usually in place in high traffic or cross
Megohm meter (Megger): An electronic meter designed to determine resistance in millions of ohms,
relevant to this article, checking for leakage due to the breaking down
of insulation on in ground magnetic flux loop wires used to control parking
control arm actions.
Zone of Danger: The area immediately under the path of a descending parking control arm
and any immediate area where a pedestrian could be struck by a descending
arm without notice.
Parking Control arm injuries occur frequently. These injuries are often
the result of a deferred or non-standard installation or maintenance protocol.
They occur equally to standard compliant installations when pedestrians
just do not pay enough attention to their surroundings.
For further information regarding requirements for parking control arms,
and other access injury issues such as overhead and sliding gates and
control points that use in ground control loops, contact Sharon at Michael
Panish’s office 888 902-4272, and visit www.ConstructionWitness.com.
If you would like to discuss a case with Mr. Panish, he is retained evenly
for plaintiff and defense claims and can assist you. He has been retained
on over 1450 cases to date since the year 2000 and has been the retained
expert on parking control arm cases across the country. Mr. Panish has
been called upon to discuss installation conditions prior to new construction
and help the owner determine the best way to accomplish the desired goals.