A classification is used to determine a Level of Service for charts and other CHS products and services. The risk levels are defined as High, Medium and Low with the High-risk areas receiving more of our resources and more frequent updates. Many factors are considered in the risk assessments such as the number of accidents in a given area, tanker routes, traffic, infrastructure, navigational complexity, and more.

For more information, please visit the Levels of Service section of the Canadian Hydrographic Services web site: http://www.charts.gc.ca/about-apropos/los/los-eng.asp