"Qantas offers the most generous amount of cabin baggage of any Australian airline and we know customers like the convenience of not having to check in luggage,'' he said.
"But we're getting feedback from regular flyers who say all customers need to be reminded about how much luggage they can take on board. So we're renewing our focus to keep cabin baggage within the allowances and to ensure everyone has their fair share of space.''
The spokesman said enforcing baggage allowances would "help reduce delays during the boarding process and ensure an on time departure", adding that "cabin bins that are too full or bags that are too heavy can cause a safety risk for both customers and crew."
Qantas limits carry-on baggage to two pieces, neither of which can be over 7kg. If a carry-on bag is found to be oversized it will be moved to the cargo hold with the rest of the checked luggage.
The spokesman said the results of the auditing may be used for an education campaign to urge customers to heed weight limits.
Virgin Australia said it warned customers at various stages of their journey, including when booking, of carry-on luggage weight limits.
A Jetstar spokesman said the airline introduced a new policy this year that allows customers to purchase an extra 3kg of carry-on baggage due to "customer insights" about the need for more.
Beauty blogger Kassandra Kashian, 23, struggles to pack light, often going over the permitted weight limit by almost double when travelling interstate with carry-on luggage.
"I find travelling interstate for work I pack about 12kg in my carry-on unintentionally but that's a laptop, charger, camera, at least one outfit, makeup and essentials as you want enough with you to get through for a few days if your luggage gets lost," she said.
"This is just under double what they expect. I am always over."
Ms Kashian said in a bid to beat the restrictions she wears her heaviest clothes on-board as well as packing her handbag with some essential items.
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