KANBrief 1/20
Potholes, cobblestones, speed bumps: uneven road surfaces like these are familiar to every cyclist. The extent to which vibration and shocks caused by such surfaces reach the rider depends, among other factors, upon the design of the bicycle. KAN is lobbying for this vibration to be covered by standards, since bicycles also serve in many areas as work equipment. Pedelecs account for a rising proportion of these bicycles.
Depending upon the circumstances, postmen and women, bicycle couriers and police cyclists may spend several hours each day on their bicycles. Increasingly often, the bicycle is a pedelec. A pedelec motor, which has a maximum continuous rating of 0.25 kW, supports the rider only as long as he or she pedals, and only up to a maximum speed of 25 km/h. Riding a pedelec exposes the cyclist to a range of vibrations, and both hand-arm and whole-body vibration. Studies conducted on cargo pedelecs by the Institute for Work Design of North Rhine-Westphalia (LIA.NRW) (pdf) have shown that on certain road surfaces in particular, such as gravel and cobblestones, vibration arises that could pose a risk to the rider's safety and health.
When conducting his risk assessment, the employer must consider the vibration caused by use of a bicycle. Depending upon the quality of the roadway and the amount of time spent riding, bicycles equipped with suspension or damping may have to be selected at purchase. For this purpose however, the employer requires comparable vibration emission values for the bicycles under consideration.
Pedelecs lie within the scope of the European Machinery Directive. Current EU law requires them to be designed and manufactured in such a way that risks presented by vibration are reduced. In addition, manufacturers must provide information on the vibration transmitted by the machine to the upper limbs and the whole body. This information must be included both in the instructions for use and in sales literature stating the specifications of the pedelec. It follows that this requirement should also be set out in the relevant product standards. A legal provision to this effect does not exist for bicycles without power assistance from an electric motor.
At present, three main standards exist in Germany for pedelecs, i.e. Electrically Power Assisted Cycles (EPACs):
The standards governing EPAC mountain bikes and transportation and cargo bikes reached the public enquiry stage in 2019. The current versions of these standards do not address vibration. Vibration is classified as not applicable in Annex ZA of the two European documents. This annex describes the relationship between the European standard in question and the Machinery Directive.
In conjunction with LIA.nrw, the DGUV's Postal deliveries subcommittee and the Federal Institute for Occupational Safety and Health (BAuA), KAN has submitted comments on the two draft standards, calling for:
In a comments resolution meeting concerning the standard governing transportation and cargo bikes, it was stated that the vibration is not caused by the pedelec itself, i.e. by its motor, but by use of the pedelec on uneven surfaces. It was argued that vibration values do not therefore need to be stated. This conflicts with the Guide to application of the Machinery Directive (pdf), which explicitly includes vibration caused by movement of the machine on uneven surfaces in the evaluation.
One obstacle to implementation of KAN's position however is that as yet, no measurement standard exists for the vibration emissions of bicycles. A standardized measurement method is however necessary in order for comparable values to be obtained and the vibration attenuation measures subsequently to be evaluated.
KAN is also discussing this issue with the responsible standards committee. The objective should be for a vibration measurement standard to be developed that can be used for measurement and declaration of the vibration emissions.
Dr. Anna Dammann