🌎 Maritime Optima Pro is a data and knowledge driven maritime software empowering you and your colleagues to work from anywhere.

What are Load Lines

Load line is a special marking positioned amidships of the vessels which depicts the draft of the vessel and the maximum permitted limit in distinct types of waters to which the ship can be loaded.



S = Summer, W = Winter, T = Tropical, F = Fresh water and TF = Tropical Freshwater.

It influence the cargo intake of a vessel and the different zones changes during a year as described in the table below and in the load line map of Maritime Optima.

In the 1966 Load Lines convention, adopted by IMO, provisions are made determining the freeboard of ships by subdivision and damage stability calculations. The regulations take into account the potential hazards present in different zones and different seasons.

The International Navigating Limits (INL), formerly Institute Warranty Limits (IWL), were revised and renamed by the Institute of Chartered Underwriters in London, United Kingdom, in 2000 and became effective in November 2003.

The term IWL is still found in charter parties and related documents and should be updated to refer to INL because there are significant changes in some areas.

The lWL zones are:

How to see Load Lines limits on the map

You can check different zones in the Load Line Map layer in Maritime Optima. This filter may be found in the menu on your right side, Map Layers icon.

If you use Maritime Optima Pro as a mobile app, you can also use Load Lines as an additional layer. Just go to the bottom menu and choose Map Styles from there.

To find the information about different areas, click at the areas you are interested in.

Next steps

After you started to work with map layers, here are some tips for you what to do next:

  • Check out this video to see how to use map layers in the app

  • Study our User guide to learn how to set up different features in Maritime Optima Pro and try them out

💡 We recommend you to use both the mobile app and desktop application to get the best of Maritime Optima Pro. Use the same login. Synced in real-time.

If you have any problems or questions, let us know in the chat box or send an e-mail to post@maritimeoptima.com and we will help you.

Did this answer your question?