Pole Inspection Method
The pole inspection process will identify decay, measure and quantify structured voids and estimate the remaining strength. Wood is not a homogenous material. Natural variables by species, and growing conditions [missing something here..] even sound wood challenges to offer an inspection process.
Biological degredation is also varied and complex. No machine has been developed which will evaluate all this variables. A trained experienced pole inspector using proven tools and techniques, while not perfect, still provides the most accurate inspection.
Visual Inspection
This is superficial inspection of the structure above groundline used to find gross defects, these include but are not limited to:
- Mechanical, lightning, and fire damage
- Woodpecker holes
- Cross breaks
- Cracked, broken, Decayed, or missing crossarms and braces
- Defective or missing hardware like insulators and nuts
- and in severe cases decay
Sounding Inspection
This inspection process in conjunction with a visual inspection has the inspector vigorously sound the above ground portion of the pole with a hammer, listneing and feeling for less obvious defects such as:
- Above ground voids likely caused caused by decay, or insects
- Loose shell
- Overhead hardware that may have loosened
Boring (invasive core sampling)
Using a bit or increment borer the inspector probes areas identified as suspect through sounding and visual inspection, along with areas which are generally susceptable to decay. When a void is discovered the inspector will do the following:
- Quantify the size of the anomally
- Determines cause of void i.e. decay growth, insect damage...
- Estimates reduction in poles strength
- Determines if the structure meets service thresholds
- Recommends (and where applicable implements) corrective measures
Excavation
Excavation is required to identify and asses defects below groundline. These can be divided into two categories
| Full Excavation | Partial Excavation |
- Fully exposes the pole surface to a depth of 18 to 24 inches below grade
- Allows the inspector to probe for deep internal decay 2 and a half feet below groundline
- Almost total examination of area most prone to decay
- Surface decay can be totally removed this is the only way to terminate progression
- Remedial treatment supplements original pressure treatment and significantly increses pole life
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- Exposes a portion of the pole below groundline
- Surface decay and minor insect infestaion can be identified
- Allows some examination of the area most prone to decay
- Increases the probability to identify degraded poles
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Choosing the appropiate inspection method
Geography, species, age, previous maintenance history, and budget constraints are all considerations. Pole Maintenance Company can help you tailor a pole inspection program specific to your unique cirmustances, and needs.
For more details on the various inspection methods available or assistance in developing an inspection program please contact William Abbott at (402)563-2663 or by email at pmc@pmcpole.com.
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