Rules and gear that changed, 1972-2010

Boats by era, 1975–2010 · Power & sail

Several federal rules and navigation systems changed while these boats were being built. The dates help you judge what an older boat was built to, what paperwork to expect, and which gear is now obsolete.

Hull identification numbers

• Today's HIN has 12 characters: a 3-character builder code, a 5-character serial, the month and last digit of the year built, and the model year. Two sources date this format as mandatory from August 1, 1984.
• Older boats may carry an earlier format, and some very old boats have none. The Coast Guard tells states to verify HINs, including the builder code. Match the HIN on the transom to the title or documentation.

Sewage rules

• The Clean Water Act of 1972 set up federal control of sewage from boats. Coast Guard rules define a new vessel as one whose construction began on or after January 30, 1975.
• Today the rule doesn't depend on age: every boat with an installed toilet must have a working, certified marine sanitation device. A head that pumps raw sewage straight overboard doesn't meet it.

Electrical safety rules

• Coast Guard electrical rules for boats with gasoline inboard engines were first published in January 1977 (33 CFR 183 Subpart I). They cover ignition protection, battery installation and overcurrent protection.
• The rules show how requirements shifted: boats built before August 1, 1985 may use a battery disconnect switch in place of a fuse or breaker within 72 inches of the battery on some circuits.

Navigation and radio

• Selective Availability, the deliberate degrading of civilian GPS, ended just after midnight at the end of May 1, 2000 (US Eastern time). Accuracy improved overnight without new equipment.
• DSC became mandatory in VHF radios type-accepted from June 17, 1999. Loran-C transmissions began shutting down on February 8, 2010.

Engine emissions

• EPA emission standards for new recreational marine diesels over 37 kW (50 hp) were adopted in 2002 and phased in from 2006 to 2009 by cylinder size. Engines built before then weren't certified to them.

Sources disagree on When hull identification numbers became required — left out rather than guessed. Check your local authority.

General guidance for recreational boaters, researched from the sources listed and written in our own words. Your equipment manuals, local knowledge, the Navigation Rules and a qualified instructor come first.