This is likely the real reason some cruise lines are returning to in-person muster drills — and it has nothing to do with safety

Is the way many cruise lines handle safety drills at the start of sailings unsafe?

One of the world's biggest cruise operators, Norwegian Cruise Line, suggested as much last week when it changed the way it handled safety briefings on ships.

In a short and somewhat vaguely worded statement, the line cited "the safety of our guests and crew" as the impetus for an abrupt return to mandatory in-person safety drills, known as muster drills, for passengers at the start of sailings.

The in-person drills will take the place of "e-muster" drills that involve passengers reviewing safety information electronically on their smartphones or on cabin televisions on embarkation day.

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Still, if there is a safety issue with e-mustering, it's not something that most other lines are seeing, nor is the U.S. Coast Guard, which reviews safety plans for cruise ships.

Over the past four years, many cruise lines have switched from in-person muster drills to e-mustering, calling it a major improvement for passenger comfort while also a better way to do safety briefings from a safety point of view.

The world's two biggest cruise brands, Royal Caribbean and Carnival Cruise Line, have both said in recent days that they would continue offering e-muster safety briefings on ships, suggesting that it was an innovation of recent years that enhanced passenger safety.

In a statement sent to TPG, Carnival hinted at what could be the real reason that Norwegian is doing away with e-mustering on ships: It requires more staffing to do.

Cruise lines that use e-mustering must position crew members at muster stations for several hours on the first day of a cruise so that passengers can visit the stations for a brief orientation — a requirement of e-mustering. The result is that a significant number of crew members are tied up on embarkation day with the e-mustering process.

Related: The ultimate guide to Norwegian Cruise Line

"E-muster requires more staffing resources," Carnival noted in its statement to TPG. "But our experience with the e-muster process has been extremely positive, and we are able to provide our guests with critical safety information in a more individualized manner, including them understanding very specifically where their muster station is and how to get to it."

In other words, Carnival sees the e-muster process as, if anything, safer than the old style of in-person mustering.

"Our implementation [of e-mustering] has also received very positive feedback from the U.S. Coast Guard and other safety experts, as well as generated positive comments for effectiveness from our guests during our post-cruise survey results," Carnival added in its statement to TPG. "We will continue to utilize our e-mustering process while always looking for ways to improve its effectiveness."

In a statement to TPG, Royal Caribbean Group also suggested e-mustering was a better way of doing safety briefings on ships than in-person muster drills.

"Royal Caribbean Group created and implemented the Muster 2.0 experience to improve safety onboard, and enhance the overall guest experience," the company said in the statement. "Royal Caribbean Group and its brands have no plans to change its Muster 2.0 experience, which has received overwhelmingly positive feedback from guests worldwide."

Royal Caribbean Group is the parent company of Royal Caribbean, Celebrity Cruises and Silversea Cruises. It also owns a partial interest in Germany's TUI Cruises and Hapag-Lloyd Cruises.

Related: The 8 types of Norwegian Cruise Line ships, explained

Norwegian did not mention staffing issues or cost-cutting in its statement. However, the line's move away from e-mustering comes as it is cutting costs in several other onboard areas by reducing passenger service and amenities.

In recent weeks, Norwegian announced that room stewards on its ships would no longer tidy up cabins twice a day, cutting the servicing of rooms fleetwide to just once per day. It brings to an end an elevated level of service that has been a hallmark of the line for decades.

The line has also recently cut entertainment offerings on ships, closing big-name production shows on vessels, such as "Kinky Boots," that were hallmarks of the brand.

The cutbacks have come even as Norwegian has sharply hiked fees for onboard service as well as other onboard fees. The line pushed through an unprecedented 25% hike in service fees for passengers in most cabins on Jan. 1.

The brand also recently increased the cost of its Unlimited Open Bar Beverage Package by about 10%, to $109. The cost of a higher-end drinks package shot up to $138 — the highest level for a drinks package in the cruise business.

The cutbacks to service and hikes to fees are occurring as Norwegian's parent company, Norwegian Cruise Line Holdings, is trying to restore its balance sheet after three years of massive losses. The company also recently laid off about 9% of its shoreside staff.

Other than its short statement on the topic, Norwegian would not comment to TPG about its elimination of e-mustering on ships.

Related: Why we love Norwegian Cruise Line's new Norwegian Prima

"The safety of our guests and crew members is our number one priority," was the specific wording of Norwegian's statement. "We continuously evaluate our procedures for providing detailed instructions on safety and security measures to our guests, and as such have made the decision to reinstate synchronized, in-person muster drills on embarkation day across all vessels within the fleet."

A spokesperson for Norwegian told TPG the line had nothing to add on the topic at this time.

In addition to Norwegian Cruise Line, two sister brands owned by Norwegian Cruise Line Holdings — Oceania Cruises and Regent Seven Seas Cruises — also have returned to in-person muster drills.

One other major line, Disney Cruise Line, also switched back to in-person muster drills in November, citing safety.

"We regularly review our processes and made the decision to return to in-person assembly drills in November to ensure all crew members and guests are fully aware of our safety procedures in the event of an emergency," the line said in a statement sent to TPG.

Royal Caribbean Group was the first cruise company to implement an e-mustering system on ships, after developing the technology over the past decade. The new system has won widespread praise from cruise passengers and industry watchers, including an innovation award from TPG.

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