British Airways is reducing the amount of hand luggage each passenger can take on board with them, to limit the chance that the overall cabin allowance is exceeded.
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In an email sent to customers, it said that the change was being made following an increase in delays resulting from too many people attempting to take on more than they are entitled to.
In recent months we have seen an increase in customers travelling with hand baggage that exceeds their allowance. We always try to accommodate our customers where we can but to make sure the aircraft is ready to depart on time.
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Passengers are allowed two pieces of luggage in the cabin with them, one of which remains unchanged at a maximum size of 56x45x25cm. The other, however, has been reduced from 45cmx36cmx20cm to 40x30x15cm.
From now on customers travelling in all cabins except First and Club World will be given a yellow tag for hand luggage items that fit within the dimensions, to ensure they can take the bag on board with them. If a person's baggage is too big, however, they will required to put it in the hold.
The change follows last month's announcement by the International Air Transport Association (IATA) that it is shrinking the standard size of carry-on luggage for airlines including Lufthansa and Emirates.