The DOT now plans to combine rulemaking procedures on airplane lavatories into one broader final proposal.

The DOT will combine rulemaking procedures on airplane lavatories into one final proposal. Skycolors/Shutterstock

A DOT regulation would require airlines to make at least one lavatory on large single-aisle planes big enough for a disabled passenger to move around in a wheelchair.

An assistant would need to be able to move around.

The rule applies to single-aisle aircraft with at least 125 seats. The requirement would only apply to aircraft that are either ordered at least 18 years after the regulation is finalized or delivered at least 20 years after the regulation becomes law.

The 2016 agreement was negotiated between airlines, flight attendants, aircraft manufacturers and disability advocates. The DOT said in a notice published March 18 that the proposal uses 18-year and 20-year timelines because it is honoring an agreement. The department encouraged stakeholders to weigh in on the lengthy timelines before a final rule is determined.

Over 25 million Americans have mobility issues that may require accommodations when flying, according to a notice. As the department moves forward with this rulemaking, including the drafting of any final rule, the department will firmly bear in mind its commitment to equity, including seeking information relating to whether these accessibility improvements can be implemented more quickly than currently proposed.

The DOT has initiated two rulemakings related to lavatory accessibility on single-aisle aircraft. The department proposed a series of requirements that would make at least one lavatory on each single-aisle plane with 125 seats more accessible to disabled people without being enlarged.

The lavatories would have to have assist handles. Call buttons and door locks need to be accessible from a seated position. Touch would have to be used to see the controls and dispensers.

The regulations that apply to new aircraft beginning three years after the regulations are finalized are still pending. The DOT decided to gather additional design information before issuing a final rule after reviewing comments on the proposal.

The DOT will combine the rulemaking procedures into one final proposal.

The public can comment on the proposal at Regulations.gov.

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There is a proposal for wheelchair accessible lavatories on planes.