My experience with sea containers is living in one (converted to serve as an 'apartment') while serving in Kandahar Airfield, Afghanistan. In this context, it was luxury accommodation. With the right equipment, they are easily moved and set in place. However, most museums don't have access to that equipment or people trained to use that equipment. You will have to with a rail yard, a port or a trucking company.
The good news is that they are solid well sealed units. You can drive a forklift into them to unload. The bad news is that they are well sealed unit. Any humidity in the unit will stay trapped in the unit will stay in the unit. There is no ventilation. They also will heat up considerably during the day, especially in the summer. The unit I lived in had an air conditioner, when it broke down, it got very hot in there which was a problem if you were on a night shift and sleeping during the day. The roof is flat and have depressions which can fill with water after a rain storm, and will eventually rust and leak. These units are made of low grade steel and, if buying used, the paint will be faded and compromised.
Merchant shipping lines use these containers for pretty much anything we get from overseas. Usually it is on a ship for no more than a week, so heat the microclimate is not as much of a problem for most applications. Some containers have air conditioners built into them. In some cases, one door will be removed while the ship is in transit, for example shipping melons from China to California.
A moderately skilled welder can modify the unit to improve ventilation or even retrofit air conditioning (hopefully with better quality than ones we had in Afghanistan). I would not recommend placing on dirt. it would be better to have a concrete pad with some provision to prevent trapped moisture on the underside of the container, which will also rust. I would also suggest a roof over the the unit with an airspace to keep the rain and the sun off of the top of the unit. Unless you have an extraordinarily robust artifact, these are not lock up and forget places to store things. A lot can go wrong if you are not paying attention.
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Alan Hawk
Museum Specialist
National Museum of Health and Medicine
Silver Spring MD
alan.j.hawk.civ@health.mil
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