from a product design and material testing perspective . . .

A major headache for the design engineer, specifiers and moulders on a worldwide basis is the fact that test data published within polymer suppliers data sheets in most cases is simply unreliable. Rota Design argue that if the industry is to move forward the polymer suppliers must present us with accurate information about the performance of their products in both the short term and long term, and in addition, let's have a harmonised testing and reporting procedure.

When we design a steel structure it is practice within the industry to calculate the loading imposed upon the beams and columns to enable us to select an appropriate grade of steel and suitable sections to achieve any given factor of safety. In support of this, we refer to national and international standards which set minimum characteristics for tensile and flexural strength etc. backed up with actual test certificates from the steel mill for a given batch of steel i.e. Certificates of Conformity.

The recently published Euro Norms for the construction industry specify the manner in which these calculations are to be undertaken and published. If we adopt this procedure we can be sure that the materials and sections selected are fit for purpose for the use intended and the structure will not fail under load. You may imagine the effects of the collapse of a building, tunnel, bridge or crane due to negligence of the design engineer.

When we draw a parallel with the rotational moulding industry and the manner in which the polymer suppliers feel fit to represent their products (or an alternative view maybe that they misrepresent their products), well, there is no comparison.