This document provides guidance on taking and handling samples that are collected as part of an investigation into the likely source of a crude oil or petroleum product spill into a marine or aquatic environment. Guidance is given on taking samples from both the spill and its potential source.

If samples are to be used in connection with legal proceedings, this document should be read in conjunction with any documents issued by the regulatory authorities in the country and location where the spill has occurred.

Taking samples may involve hazardous materials, operations and equipment. This document is not intended to address all the safety and health aspects associated with the guidance given. It is the responsibility of the user to consult and establish appropriate safety and health practices and determine the applicability of regulatory limitations prior to use.

For the sake of clarity the word ‘oil’ is used throughout this document to mean either crude oil, a petroleum product or mixtures of such.