This industry comprises establishments primarily engaged in providing navigational services to shipping. Marine salvage establishments are included in this industry.

Cross-References. Establishments primarily engaged in--

• Providing water transportation of barges (except coastal or Great Lakes barge transportation services)--are classified in U.S. Industry 483211, Inland Water Freight Transportation; and
• Providing coastal and/or Great Lakes barge transportation services--are classified in U.S. Industry 483113, Coastal and Great Lakes Freight Transportation.