Here’s an in-depth overview of the various specifications for Flexyfoot products inclusive of materials, testing and trials. There’s quite a lot of detail here but if you have additional questions regarding specifications, please do get in touch.
Flexyfoot has been developed to the highest specifications, to ensure the best walking experience for our customers.
Moulded from high performance polypropylene, Flexyfoot ferrules use the unique integral hinge properties of polymers. When correctly designed, the molecules in a polypropylene hinge align themselves across the hinge line, making it almost indestructible. The more the hinge area is flexed, the stronger it becomes. The Flexyfoot bellows consists of a series of multiple hinges and has been tested to 500,000 compressions or 1M steps with a load of 50KG. That is the equivalent of 300 miles of walking!
Flexyfoot has been put through a long-term development test programme with each feature tested for performance, endurance and safety before moving to the next stage. We designed and built our own test machines at the start because there was no standard that would subject Flexyfoot to real-life conditions.
This video shows our testing rig, and Flexyfoot being tested.
Life expectancy and endurance
Part way through the development, a draft standard, BS ISO 24415-2 was published by British Standards that was almost identical to the test programme that we designed and so we built a test rig that would test Flexyfoot to the draft standard. It basically ‘walks’ the walking aid while applying a load of 50kg during the compression cycle and the ferrule or tip is tested for 500,000 cycles. It cannot split or show any internal parts.
We initially carried out these tests in-house using our test rig and then asked SATRA, a highly regarded independent test house to repeat the tests on three production samples. Each sample takes around 13 days of 24 hours continued testing. The results were great; there were no splits or damage to the bellows, collar or rubber tread and the fit of the foot into the collar was as new. Tread wear was also excellent, a point raised in feedback where customers have told us that Flexyfoot lasts around 4-8 times longer than a standard ferrule (depending on the user, the aid and the conditions). We tested a standard ferrule on the rig and the tread had totally worn away on one side within 35,000 cycles!
We were also concerned about cold weather performance, which isn’t actually part of the British Standard test. With this in mind, we tested Flexyfoot at -25 degrees in a cold chamber to ensure that the cold would not make the plastic brittle and liable to cracking – and it’s not!
Due to the fact that the entire tread makes full contact with the ground, we expected that Flexyfoot’s grip would be very significantly better than a standard ferrule that only has part of the tread in contact, particularly at first when the person is at their most unstable.
The BS ISO 24415-1:2009 test is designed to measure the grip when the ferrule makes contact with the ground at an angle of 20 degrees. This simulates someone placing a walking aid on the ground during a step. A load is applied to the ferrule while it is pushed across a glass plate and the friction between ferrule and plate is measured.
SATRA tested three production samples and compared these with a standard ferrule. Flexyfoot has at least 50% more grip than a standard ferrule and the wet surface performance was also good. These results match the feedback from our customers who say that they feel much more secure and less likely to slip particularly in the wet.
CE marking certifies that a product has met EU consumer safety, health or environmental requirements. Flexyfoot is classified as a Class I device and so can be self-certified, as long as due diligence is observed and supporting materials are supplied. To help, we asked medical device consultant, Dr Jed Place of Medical Device Consultants, to guide us through this highly technical and detailed process.
Flexyfoot was registered with the MHRA (the Medicines and Healthcare products Regulatory Agency) in December 2009.