Southwest Airlines has confirmed to CBS News that the intense summer heat is causing soda cans to burst after being loaded onto some of its flights. Airline officials reported a series of incidents where cans of carbonated drinks have ruptured, often during opening, resulting in onboard messes and about 20 employee injuries so far this summer.

The incidents have led to several hand injuries among flight attendants, including one requiring stitches. Southwest noted that while such injuries were reported last year, the issue seems more frequent this summer, drawing increased attention.

Southwest Airlines is taking measures to address the problem, especially in hotter locations like Austin, Dallas, Houston, Phoenix, Las Vegas, and Sacramento. Chris Perry, a Southwest spokesperson, mentioned that the airline has been communicating with employees about the issue throughout the spring and summer and has developed a mitigation plan.

The problem may be linked to how Southwest stores and loads drinks on planes in extreme heat. Unlike other airlines, Southwest does not stock perishables on board and thus does not use air-conditioned catering trucks. Consequently, drinks on Southwest's provisioning trucks are more exposed to outside temperatures.

An internal email obtained by CBS News, dated July 12, was sent to flight attendants with the subject "Hot & Bursting Cans: Provisioning Procedural Changes." The email, from Rachel Loudermilk, managing director of base operations, and Matt Sampson, provisioning director, emphasized that finding solutions to the issue is a top priority.

The email outlines several changes Southwest has implemented since the start of the summer to address the issue, particularly in hot cities. These changes include stocking fewer cans on provisioning trucks to reduce their exposure to heat, placing carbonated drinks in coolers, monitoring truck and can temperatures with thermometers, and avoiding loading products when outside temperatures reach levels that increase the risk of bursting cans. Employees have also been instructed not to open cans that are noticeably hot to the touch or deformed due to heat exposure.

Southwest has decided to halt the onboarding of cans with a temperature of 98 degrees or higher, returning them to the warehouse to cool down. The airline is also considering using refrigerated trailers at warehouses to keep cans cool before loading them onto provisioning trucks.

The email indicates that Southwest began testing air-conditioned provisioning trucks this month and is discussing with Coca-Cola the viability of the current cans and possible alternatives, including a 7.5-ounce option. Currently, the airline stocks traditional 12-ounce soda cans. During tests in Arizona and Nevada, cans are being marked to identify if they came from refrigerated or non-refrigerated trucks.

Perry emphasized that Southwest is taking the issue seriously, stating, "We are investigating the issue and looking at changes to ensure safety for our employees and customers in the midst of extreme temperatures and climate change."

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