This document specifies test methods for the determination of the degree of disintegration of plastic materials exposed to marine habitats under real field conditions. The marine areas under investigation are the sandy sublittoral and the sandy eulittoral zone where plastic materials can either be placed intentionally (e.g. biodegradable fishing nets) or end up as litter due to irresponsible human behaviour. This depends on their physical characteristics, form and size of the materials, and on water currents and tidal movements. This document specifies the general requirements of the apparatus, and the procedures for using the test methods described. The determination of the level of disintegration of plastic materials exposed to pelagic zones such as the sea surface or the water column above the seafloor are not within the scope of this document. This document is not suitable for the assessment of disintegration caused by heat or light exposure. The described field test is a disintegration test and not a biodegradation test. Therefore, it cannot be used for demonstrating biodegradation or for making unqualified claims such as "biodegradable in marine environment" and similar.