28 september 2018
The storage samples are very valuable when further research of a consignment of mineral wool needs to be done. Therefore, RHP advises growers to take a sample during delivery or implementation and store it. The grower is responsible for this, as the volume of the slabs makes it impossible for the producer to store samples for all their customers. This is however possible for (the smaller) blocks. The RHP certified companies Cultilene and Grodan produce and deliver slabs and blocks of mineral wool under the RHP quality mark for substrates.
The procedure for taking storage samples of slabs of mineral wool is described in the RHP product certification scheme and you can download the procedure at: www.rhp.nl/en/product/mineral-wool
A storage sample is a sample that is representative of a complete packaged unit of an end product consignment. In case of problems and/or complaints in the culture it is important that there is unused material available. Material that has the same properties as the material that has been implemented in the culture. With this research can be done. Ideally a storage sample consists of a minimum of 12 undamaged slabs of mineral wool with cover, taken randomly from the delivered consignment. The slabs need to be stored for the entire culture season in a dark, dry, dust free place with a temperature between 0 and 30 degrees Celsius, without straining or pressure.
RHP certified substrates establish an optimal start of the culture. With the RHP quality mark you increase the certainty that the substrate meets the right quality norms for, for example, water uptake, air content, pH, EC and nutrients. It also offers more security that the substrate is pure and clean and that it can be used safely without risks for the culture. The RHP quality mark monitors the quality of the growing media in the chain, from excavating raw materials to processing and delivery at the company of the user. RHP has been the European knowledge centre for substrates since 1963.