Abtech AB15RT Fall Arrest Recovery Winch
With reference to fall arrest retrieval blocks and Man riding winches.
Regulatory bodies hold the manufacturer responsible for use of equipment and service regimes.
It is the responsibility of the manufacturer to decide if their fall arrest retrieval block may be used for access and egress from a confined space. The block needs to have been tested to the same standard as the man riding winch (BS EN1496) and the manufacture should be confident that the device will fulfil all requirements of use.
BS EN1496 is not a harmonised European standard. This means that not every country in Europe adopts the standard. The standard is adopted in the UK. So it is best practice that any device used as a man riding winch in the UK is approved to this standard. Man riding winches should have back up brakes that will activate if the winch mechanism fails.
It is the responsibility of the manufacturer as to how often and when their products need to be serviced. Some manufacturers do want fall arrest retrieval devices returned after they have been used for either a fall arrest or if the winch mechanism is used. Many other manufacturers only require the device to be returned for service if the fall arrest indicator is activated. There is a commercial aspect to this.
There is quite a long boring history to these devices. It is relevant to the development of the actual devices and how they are used today.
It is generally accepted that the first fall arrest blocks with a retrieval capability came from a German company and a British company at approximately the same time. A gear ring was added to the rope drum and a pinion shaft with a handle located in the housing. The pinion shaft was fitted through a one way bearing in the housing that allowed the shaft to move in only one direction. This device would only raise the user after a fall. This is the source of the name retrieval device or recovery device.
The next design modification was to make a device that would allow the user to be lowered and raised. The one way bearing was taken away. A winch mechanism was added to the pinion shaft; ratchet for raising and two friction discs and a thread for lowering. This device was meant to be used for access and egress to and from a vertical confined space. The problem at the time (1980’s) was the quality of the friction discs. It was found by the UK manufacturer that after approximately thirty uses (lowering of user) the friction discs wore out. The user could still be raised and would still have the fall arrest facility but they could not be lowered. At this point it was decided to specify the retrieval a device as a rescue only option.
Since that time (1980’s) the friction discs of the winch mechanism have improved significantly. A user can be lowered and raised many hundreds of times. As a result of these improvements some manufacturers (Abtech Safety included) have deemed it safe and appropriate to use their fall arrest retrieval device for fall protection and access to and from vertical confined spaces.
This history may not be completely accurate as it comes from a couple of old fossils who work for Abtech Safety who were there at the time and involved in these developments.