Concept of HNS

Shipping is a practical way of transporting large quantities of goods over long distances. This is particularly the case for large volumes of chemicals. In order to more accurately identify the risks that chemical transport presents, the concept of Hazardous and Noxious Substances (or HNS) was created. A HNS is defined as any substance other than oil which, if introduced into the marine environment, is likely to create hazards to human health, to harm living resources and marine life, to damage amenities or to interfere with other legitimate uses of the sea (definition from the OPRC-HNS Protocol).