Safety Technology were approached by Electricity Northwest to review the current pole choking belt used to climb overhead lines. They briefed us to develop a new device with a belt that was easy to adjust, would stop the user as quickly as possible in the event of a fall, could not be “cheated” when used (could not be used to climb unless the full choking capability was engaged) and that it was cut resistant.
What we did
For each requirement of the device we needed to take a different approach compared to our existing belt and other options that were available:
Adjustment – Our design team studied existing work positioning belts that were commonly used in the industry and incorporated the design features into the Polecat.
Cut resistant – Working directly with a number of rope manufacturers we developed a rope with the highest cut resistance that would still function as a normal rope.
Short stopping distance – We tested a number of choking design combinations that would give the required stopping distance but still maintain the ability to pass any furniture on the pole. The combination we arrived at was so successful that it necessitated the addition of a small shock absorber into the design to prevent impact forces in the event of a big fall. These design elements have subsequently been patented.
Cannot be “cheated” – Some belts allow the user to disconnect the choking element of the belt to pass an obstacle. If the belt is not reconnected the user can climb with the belt as a standard strap and this can be unsafe. The choking design of the Pole Cat is such that the user cannot climb unless the choking part is engaged thus ensuring an additional safety measure for workers.
The polecat belt comes in two colours, red and yellow, both are bright so that they are clearly visible on the pole and it’s easy to spot when they are being used.
Through all stages of development, EWN were involved with the development process and testing of prototypes. Working in partnership like this enabled modifications to be added during trials and development meetings had the added benefit of real user feedback.
One such key modification was a version specifically designed for the small diameter poles in the fleet that could choke down to 125mm.
The collaborative design and testing process ensured a product was developed that met the exact client requirements across a range of scenarios. This was simply not achievable with the off the shelf solutions that ENW had in use previously. The Polecat represents a step change in safety for the linemen in the field using the Polecat.