The hinge on the left is a stainless steel 4″ ball bearing butt hinge spotted on a fire door in the gents’ toilet of a busy Exeter department store. The hinge on the right is a new stainless steel 4″ ball bearing butt hinge, pictured for comparison purposes. The top bearing has collapsed, its ball bearings have been lost, the washer can be seen protruding out of the joint like a slipped disc. The effect of this is that the whole weight of the door is resting on the centre knuckle which has compressed onto the collar below causing them to wear each other away. The degraded state of this hinge increases the opening force potentially causing it to fall foul of the recommendations of BS8300 (DDA/The Equalities Act). A Hi-load hinge, such as the Royde & Tucker H102 fixed pin hinge, would have been a much better choice for this door. Why?
1. The frequency of use for this door could be reasonably predicted to be very high
2. The width of the door was at least 926mm, a long lever (wide door) exerts more power at its axle (hinges) than a shorter one (or narrower door)
3. The door had a door closer, which increases the “adjusted door weight” thus; a door closer adds 20% to the weight, and a back check door closer adds an additional 75%