Finnair has temporarily withdrawn several of its Airbus A320 aircraft from service and cancelled around 40 flights after discovering that seat covers on the planes had been cleaned using a method that could affect their fire resistance.

As reported by Yle, the airline said the decision was made purely for safety reasons after a review of maintenance procedures found that the seat covers on some A320 aircraft had been washed with water — a process whose impact on the materials’ fire protection properties “had not been properly verified.”

Finnair’s head of communications, Mari Kanerva, explained that the issue was detected during routine airworthiness checks. “We take safety very seriously, and while there is no indication of an immediate risk, we are conducting additional inspections to ensure full compliance with safety standards,” she said.

As of Monday, October 13, eight A320 aircraft remained grounded for additional fire safety testing. The airline could not yet specify how long the checks would take or whether further cancellations were expected. The disruptions are expected to continue at least through Wednesday, October 15.

Finnair said it is directly notifying passengers about cancelled flights and working to rebook them on alternative departures as quickly as possible.

The timing of the incident has added complexity for the airline, as Finland is currently in the middle of autumn school holidays — one of the busiest travel periods of the season. The reduced number of operational aircraft means that available seats on alternative flights are limited.

While the number of affected flights is relatively small compared with Finnair’s total operations, the incident underscores how even minor maintenance irregularities can lead to significant disruption in a safety-first aviation environment.