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MarineLab Undersea Lab Museum

SphereExperience what it was like to live and work underwater! For 33 years, the MarineLab Undersea Lab was a working undersea research laboratory 30 feet below the surface of our lagoon. It's now on the surface (or topside, as we call it) and open to the public!

The interior has been refurbished to match what it looked like when it was first submerged in 1984. It looks and sounds like you're underwater! Visitors can measure how much CO2 they breathe out, practice their fish identification skills looking out the porthole, or check out the different species of plankton under the microscope.

The museum is designed to be experienced without a guide, with lots of interpretive signage inside and out. There is no charge for a self-guided tour. However, if you'd like a more in-depth experience, including a chance to descend into the sphere beneath the lab, please call our office at 305-451-1139.

Check out the video below of the day we brought it back to the surface.




Undersea Lab ExteriorHistory

Conceived in 1970 as an ocean engineering project at the US Naval Academy, the MarineLab was originally called the MEDUSA (Midshipmen Engineered and Designed Underwater Studies Apparatus), and provided engineering design and project management experience for several hundred midshippmen over a ten year period. The habitat was developed under the direction of Dr. Neil Monney, who was then Director of the Oceaneering Department of the Naval Academy.

Although completed in 1980, the habitat was never placed in operation by the Naval Academy. In 1984 Dr. Monney arranged to have the habitat donated to Marine Resources Development Foundation, and it was renamed MarineLab. A suitable location was found within John Pennekamp Coral Reef State Park, and agreement was reached with the then-Florida Department of Natural Resources for the use of the site. The habitat and support van were transported to Key Largo and emplaced in 1984. Operations began in June, 1984 with Chris Olstad as On-site Director. Twenty-one 24 hour missions were conducted that summer involving approximately 80 aquanauts.

In 1985, the MarineLab habitat, also called the "Classroom in the Sea," was moved to a permanent site at the Foundation's headquarters in Key Largo, Florida, where it remains to this day, although now it is on dry land rather than 30 feet below the surface.

Projects and Studies in the Undersea Lab

In 1993 and 1994, NASA’s OCEAN Project, under the direction of Dennis Chamberland, conducted plant growth experiments in one of MRDF’s undersea habitats to learn more about the challenges of maintaining a controlled ecological life support system, in an alien environment. The scope of the OCEAN Project was expanded in 1995 to capitalize on the educational value of using an undersea habitat to demonstrate the similarities between living in outer space and within the sea. 

MRDF developed an undersea diving program with the Oceanographic Ministry of the former Soviet Union in 1992. Two Soviet scientists/aquanauts from the P.P. Shirsove Institute of Oceanology of the Soviet Academy of Sciences participated in a NOAA-funded, two week saturation dive study of vital lung capacity in MRDF’s MarineLab Undersea Laboratory. The project marked the first time that Russian scientists had lived in a US undersea habitat.

These Soviet scientists were part of a larger series of NOAA funded programs studying diver physiology under a variety of hyperbaric environments.  From 1988 to 1990, researchers used Doppler Ultrasound technology to detect small nitrogen bubbles in the blood of divers who had spent 12, 24, and 48 hours at depths of 12 to 24 feet in the MarineLab Undersea Laboratory. Several papers and presentations resulted from this study, which provided new information on the no-decompression limit for divers.

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MUL's BubbleThe structure is composed of a surplus steel water tank, 16 feet long and 8 feet in diameter. There is a 3 foot diameter observation port at one end of the cylinder, and a 66-inch diameter acrylic observation sphere mounted beneath the cylinder. This acrylic sphere was the test hull for the US Navy Submersible NEMO, which was developed by the Naval Civil Engineering Laboratory, and was designed for submerged operations to 100 feet. Access to the sphere is from inside the laboratory, making it a dry observation area.  

The entire structure weighs 70,000 pounds, or 35 tons.

Cradle and Ballast

The base of the laboratory consists of a cradle and ballast tray constructed from I-beams, angle iron and concrete. Approximately 3.6 tons of ballast were required for the underwater lab to remain on the seafloor.

Internal Layout

Inside the lab are three bunks, one of which can be converted into a work bench.  It also contains a microwave oven, a refrigerator, and a sink, all of which are currently for display only. There is a wetroom which contains a shower and portable toilet. The principal access hatch for the lab is also located in the wetroom. A second hatch is located at the opposite end of the lab for emergency exit.

MUL InteriorThe main living and laboratory area is separated from the wetroom to control humidity and to maintain a feeling of normal living accommodations. All framing, partitions and shelving are fabricated from metal and have been coated with an epoxy paint system. The walls of the lab are insulated with a closed-cell, pliable foam insulation of the type used in Navy submarines.

Atmospheric Control, Power & Water

Air was supplied to the lab by a low pressure compressor via an umbilical from a surface support van. The humidity and temperature of the air were controlled, within certain limits, on shore to properly condition the lab environment. Scrubbers were not necessary for removing carbon dioxide from the atmosphere because a sufficient flow of compressed air was maintained to continually flush the laboratory and remove all contaminants.

110 volt AC power is used in the lab for refrigerator, lighting, and microwave oven. Power was provided via the umbilical from the surface, but power for emergency lighting and communications was supplied by 12 volt dry batteries in the lab. Currently, power is supplied through a 110 amp hookup, like an RV.

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Hot and cold water to the sink and shower were provided via the umbilical from the surface van.

A water level alarm in the entrance hatch signaled any decrease in air pressure in the lab. Communications between the laboratory and the support van includes a VHF radio, an intercom, a set of sound powered phones, and closed circuit TV.

Shore Support

Command Van ExteriorThe shore support facility is housed in a 20 foot van located in close proximity to the laboratory. Two low pressure compressors, located in the support van, supply primary and backup air for both the lab and hookah diving hoses. It should be noted that the lab is not equipped with high pressure air. Diving operations will be conducted on the 100 foot hookah rigs. Power to the support van is provided by a commercial 220 volt 3 phase circuit.  A diesel powered generator is housed outside the support van for emergency power.

Command Van InteriorAdditionally, the support van houses the VHF radio-intercom systems, TV monitors, bunks and a desk for the Operations Director or watch officer, first aid supplies, dive logs, emergency stand-by diving equipment, spare parts, and tools.

The umbilical carried: (1) two low pressure air supply hoses (2) communications cables for the intercom, sound-powered phone, and TV camera (3) 110 volt AC power supply (4) 12 volt DC power supply for outside lighting, and (5) hot and cold water supply hoses.

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