Cruise lines have stopped their engines and ships are waiting to resume operations; these stops, called "lay-ups," occur in different ways.
In a guide to lay-ups, the classification society Lloyd's Register lists a long checklist of actions that must be taken before and during acold lay-up. To begin with, ballast tanks are either completely emptied or filled with water plus corrosion inhibitors. In machinery areas such as engine rooms, dehumidifiers are deployed to prevent corrosion, and natural ventilation is encouraged.
Dehumidifiers would also be deployed in cabin areas and public lounges; bedding and towels would be stored in a dry place; and cabin mattresses would be stored on their sides. Refrigerated supply rooms would be emptied and left with the doors open. Reactivating a ship in this scenario could take up to three weeks.
There are several other levels of lay-ups, each with its own requirements. These include a "hot ship lay-up" where a vessel can be returned to service within 24 hours and a "warm ship lay-up" where a vessel can be returned to service within a week.
There is also a more extreme "long term lay up" designed for ships that are laid up for five years or more. This situation can take up to three months to be reversed.
All these different ways of operating a stopover also require different numbers of security crew members on board. Carnival Corporation has stated that switching from a "warm lay-up" to a "cold lay-up" configuration for its ships would save the company between $1 million and $2 million per month per ship. "We estimate the cost of a warm lay-up configuration is approximately $2 million to $3 million per month, and the cost of a cold lay-up configuration is approximately $1 million per month."
