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What Now? Assessing Damage Due To Floods
Power Distribution, Switches and Electronic Equipment
By Timothy J. Smith
Floods in the Midwest, Canada and the South…the current
threats of El Niño…fire sprinklers in your own facility—most of us could
experience significant business disruption from water damage to electrical
equipment and switches.
Do you know the potential impact on your organization
from water damage?
The Dilemma…
Critical Equipment Located
Primarily in Basements!
Typical construction has a tendency to put critical
but "ugly" items such as electrical control panels, junction boxes, environmental
controls, main telephone switches and other electrical equipment in out
of the way places—primarily in basements. The result is a foregone conclusion.
Since most companies and organizations cannot, or will not, relocate these
critical and sensitive items, it is important to be prepared for a water-damage
situation, no matter where you live.
INITIAL EQUIPMENT RECOVERY EFFORTS
Clean-Up/Corrosion Inhibiting Protocol
As soon as possible after the water damage,
water must be removed from the affected area and a Phase I "Corrosion
Inhibiting Protocol" performed. This initial phase will remove gross contaminants
and stabilize the sensitive surfaces and prevent future damage. The silt
and mud deposits must be removed from the equipment surfaces. Hot air
guns, portable dehumidifiers and large portable heaters and fans are employed
to hasten the dry-out process. Since time is often critical, little or
no disassembly of the equipment should be attempted during this phase.
To complete Phase I, all affected equipment surfaces
should be sprayed with a petroleum-based surface preservative that is
specially formulated with rust and corrosion-inhibiting properties to
stabilize metal surfaces.
Application of Phase I Efforts
The full Phase I stabilization is directed at
equipment sections directly exposed to flood water, while those sections
above the high water mark are minimally treated with the oil based surface
preservative.
The dehumidification and hot air dry-out of equipment
below the water line helps to remove trapped water and promote surface
diffusion of the preservative into even tighter interfaces. This coating
will retain its corrosive protection properties for several months in
a basement area environment, where relative humidity is below 60% and
temperature below 70°F (+/-10°F). Actual on-site readings should be taken
periodically to maintain control of the environment.
VISUAL INSPECTION GENERAL OBSERVATIONS
Metal Surfaces
Generally, metal surfaces that are painted,
plated, anodized, soldered, lubricated and otherwise protected, are found
free of visible corrosion. The significant exception to this is found
in equipment that was electrically energized during the flood water exposure.
Metal plated bus bars, fuse holders, breaker contacts and transformer
windings become discolored and corroded because of thermal effects and
electrolytic reaction with the dirty water. Solder joints on circuit modules
become dulled because of surface oxidation, and electrical edge connector
contact surfaces show some discoloration.
These signs of metal deterioration on wet energized
equipment indicate damage to sensitive electrical components within the
equipment unit. Non-critical, unprotected base metal surfaces, i.e. mild
steel and aluminum fixtures, etc. may show varying degrees of cosmetic
flash rust which is removable with minimal residual damage.
Non-Metal Materials
Dense ceramic insulators, insulated transformer
and motor windings, fuse casings, etc. can be cleaned, dried and tested
for insulation resistance to determine effectiveness of moisture removal.
Hard plastic enclosures, glass surfaces, etc. need only to be wiped clean
for reuse.
Electromechanical Assemblies
• Coil-activated relays, breaker trip assemblies, switches,
rheostats and potentiometers, etc. may be replaced for less than the restoration
cost.
• Small signal relays, switches and variable resistance
devices that have been submerged in the flood water should be replaced.
• Large capacity breakers can be cleaned and tested
if not energized during water submersion.
• Removal of cosmetic discoloration on breaker racking
gears and other non-working parts and contact relubrication where required
is part of the clean-up process.
• All energized devices having direct water exposure
need to be replaced, but devices above the water line can usually be restored.
However, the presence of residual moisture inside small signal relays
is generally the reason for replacement.
• Variable resistance devices and tripping breakers
are easily treated with contact cleaners/preservatives to remove any traces
of residual moisture from the short term high humidity environment existing
at the time of the loss.
Electrical Motors
It is common practice in the industry to restore
motors that have been submerged in water for several hours. The procedure
involves disassembly clean-up to remove silt and mud, bake-out to restore
field and armature insulation resistance and replacement of armature shaft
bearings and brush holders as required. Certification to the manufacturer’s
specifications completes the restoration project. However, it is usually
more cost effective to replace small/fractional HP motors, fans and flower
assemblies after water submersion.
Mechanical Assemblies
Gauges, valves, pumps, conduits, piping, etc.
are typically cleaned for reuse after water exposure. Exceptions are gauges
and valves that leak water into the enclosure, and piping that leaks water
into inaccessible sections causing long term rust and unacceptable cosmetic
damage. In these cases, replacement is advisable. Also, shaft bearings
and seals in pumps are typically replaced after water submersion, because
of the possibility of internal rusting of bearing surfaces (usually a
low probability occurrence).
Electronic Devices/Control Panels Assemblies
A major concern expressed by the various equipment
manufacturers relates to the effect of direct water on electronic devices
and assemblies. There is no argument that electrically energized devices
and assemblies are incompatible with water exposure. The critical part
of most of the control panel assemblies and electronic devices in the
basement equipment inventory are the printed circuit board modules. Application
of electrical bias on any wet component on these boards can lead to galvanic
corrosion and spurious voltage spikes that can destroy adjacent electronic
devices.
Identification of electronic equipment sections that
were energized during water exposure allows replacement of suspect components,
devices and modules as a first step in the restoration process. Therefore,
considerable attention should be given to those equipment sections that
were either above the water line or submerged with no electrical bias.
Once this assessment is completed and all high voltage
equipment lock out has been verified by customer’s electrician, preservation
and clean-up can be initiated immediately. As a general consideration,
electronic equipment can be briefly exposed to water without permanent
damage if not in an energized state. Water exposed equipment cleaned using
these modern restoration protocols can be returned to a better than pre-loss
condition. Barring actual physical damage to the equipment, pre-loss operational
reliability can also be restored to at least the same pre-loss level.
In the case of equipment having significant pre-loss background surface
contamination, restoration will even improve operational reliability!
COSTS AND MITIGATION SUGGESTIONS
A basement area can take 3 to 7 days to dry
using dryer equipment. While restoration costs can average 10% to 25%
of replacement value, the time to replace and the business interruption
costs of the delay could preclude replacement as an option. Consider these
mitigation ideas:
• Survey possible problems
and develop a plan.
• Have a Business Contingency Plan in place
prior to a catastrophe.
• Pre-qualify vendors necessary for restoration
and rebuilding so work can begin immediately after a loss.
• During a remodel, place equipment in non-flooding
locations.
• Consider fire suppression systems with minimum
impact on electrical equipment.
What is vital to a successful recovery is the identification
of critical equipment and components and the establishing of procedures,
through the use of BIA analytical tools, to maximize the probability of
a timely recovery and the resumption of operations. Once an event occurs,
the implementation of these procedures will minimize the impact on the
operation of the facility and insure the continued prosperity of the organization.
ELECTRICAL/ELECTRONIC EQUIPMENT CHECK-LIST
TYPE OF EQUIPMENT FOUND AT BASEMENT LOCATIONS-TYPICAL
INVENTORY
HVAC/CHILLER SYSTEMS
Blowers/motors/fans
Controllers
Compressor motors
Pumps
Gauges
Computer controller energy mgmt system
BOILERS PACKAGE UNIT
Condensers
Gauges/pumps/motors
Controller (electric/pneumatic)
Heaters
ELECTRICAL VAULTS
Breaker panels
Bus work
Terminal boards
Meters
Transformers
TELEPHONE EQUIPMENT
MDF (main distribution frame)
UPS (uninterrupted power supplies)
Cable vault
CKT breaker boards
Switch equipment-line card cabinets-trunk lines
Computer upgrades-paging systems-alarms
ELEVATOR SHAFTS
Lift motors/brakes
Controller cabinets
FIRE ALARM
Pumps
Controls/sensors
FREIGHT ELEVATORS
Lift motors
Controllers
SUMP PUMP STATIONS
Pump motors
Level controls
About the author:
Tim Smith, National Director of Marketing
for Restoration Technologies, has over 13 years in the restoration industry.
The author wishes to acknowledge Ken Greenough, PhD, Chief Scientist for
RTI for his valuable assistance in the preparation of this article. For
additional information call RTI at (800) 421-9290.
The photo on page 59 originally appeared in Disaster
Recovery Journal and is used with their permission.
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