The new -9 version of the 787 has a maximum range of 8,300 nautical miles (15,370 kilometres), or farther than Boeing's newest four-engine 747.
Special regulations for so-called extended operations are designed to ensure that commercial aircraft in the world's most-remote airspace can safely divert to an alternate airport in the event of an engine failure or fire, according to the FAA.
Read also: US 'too reliant' on Boeing for 787 battery tests
In the early days of commercial flight, twin-engine jets weren't allowed to fly more than 60 minutes from an airport because they weren't deemed dependable enough. Regulators have gradually increased the time allowed from a diversion spot amid improvements in engines and other safety enhancements.
Dreamliner buyers can choose engines made by General Electric or Rolls Royce Holdings, and both can qualify for the extended flight routes under the FAA's new policy.
Boeing's Dreamliner deliveries totaled 146 to 19 customers, according to the company. As of May 19, the global 787 fleet's tally was 97,520 commercial flights, with an estimated 18.3 million passengers.
The cases for the 787's lithium-ion batteries were redesigned last year after units in two planes overheated and, in one case, caught fire. The Dreamliner is the most-advanced model from Chicago-based Boeing, with features including an increased reliance on electricity to power the plane's systems.
Air New Zealand is getting next generation Boeing 787-9 aircraft this year but said the FAA decision had no bearing on how it would use the planes. The airline had always intended that its planes would use the three-hour rule and "had no current plans to use the extended range capability," a spokeswoman said.
- Bloomberg