When United Airlines Holdings (NYSE:UAL) announced last week that it would immediately begin requiring its flight attendants to wear face masks while on duty, the Association of Flight Attendants union welcomed the new policy. It also sent letters to the Secretaries of Transportation and Health and Human Services asking them to use their authority to also require the protective face coverings on airline passengers. 

JetBlue Airways (NASDAQ:JBLU) this week included passengers in its new personal protective equipment (PPE) policy requiring masks beginning Monday, May 4. Now, the other major U.S. airlines have also added passengers to the PPE policies. 

drawings of airline workers wearing surgical face masks

Image source: Getty Images.

United and Delta Air Lines (NYSE:DAL) will now require face coverings on passengers starting May 4, and American Airlines Group (NASDAQ:AAL) will begin the policy on May 11. 

In announcing the added layer of protection, the airlines cite the Centers for Disease Control and Prevention (CDC) guidelines that wearing simple face coverings can help slow the spread of the COVID-19 virus. The airlines have also added new operating and cleaning practices meant to help make customers more comfortable with resuming air travel.

American said it has increased cleaning frequency in gate areas, ticket and service counters, and baggage service offices. Delta said it has added employee temperature checks and is adding electrostatic spraying of employee work and break areas. United has amended snack and service procedures "to minimize touchpoints between crew and customer," related to snacks, beverages, hand towel and trash collection services.