What do heavy lines indicate in damage control practices?

Heavy lines in damage control practices signify water or oil tight boundaries. These boundaries are critical for preventing the spread of water or oil in the event of a leak or breach in a vessel or structure. By establishing these boundaries, crews can contain potential flooding and minimize damage in affected areas, contributing to overall stability and safety.

This standard helps ensure that essential compartments can be sealed off to maintain the integrity of the hull and prevent catastrophic failures, especially during emergencies such as flooding or oil spills. Understanding the purpose of heavy lines allows individuals involved in damage control to make informed decisions quickly and effectively.