The main product we elaborate in our quarry is the slate for roofs (samples are regularly tested and classified as
the highest A1 S1 T1 grades in Awarded Homologation Certification to the stringent Belgian Standard, on the
German and French market (inspected by the LNE, Paris,and authorized to use the prestigious NF mark.
What are the differences between the CE and the NF ?
The method of testing between the CE (European Norm) and the NF (French Norm) are the same regarding : A for water absorption, S for resistance to agressive atmospheres, T for risk of rust. The NF is not obligatory. The producer decides to make the tests and only the LNE (french authority) accept it or not. But
The CE is obligatory. The CE tests can be carried out by any European Laboratory. The NF have a strict procedure and tests can only be made by the LNE. The CE have less tests than the NF and have accepted lesser results than the NF. For example, the NF extends the tests to the thickness, the size and the tracibility. The testing can happen at any time during the production or the distribution which is not the case with the CE.