WLM
USCG Coastal Buoy Tender
The
United States Coast Guard commissioned a new Keeper-class of coastal buoy tenders in the 1990's that are 175 feet (53 m) in length and named after
Lighthouse keepers.These vessels and the 225 feet (68 m) Juniper class of seagoing buoy tenders replaced the
World War II era 180'
Seagoing Buoy Tender.They were the first Coast Guard cutters equipped with
Z-drive Azimuth thruster propulsion units instead of the standard propeller and rudder configuration. They are designed to independently rotate 360 degrees. Combined with a thruster in the bow, they give the Keeper-class cutters a lot of maneuverability.
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Working Level Month (WLM)
A unit of measure used to determine cumulative exposure to radon.