A freezer malfunction at the Children's Hospital Los Angeles, destroyed stored blood stem cells for 56 patients, some of whom have cancer, according to an article on the CNN website.
The freezer's temperature sensors failed and the safeguards put in place were insufficient, the hospital said.
It has since implemented several changes, including replacing the malfunctioned freezer, upgrading the sensor monitoring and alert system, and double-checking all power supply sources.
The hospital sent letters to all affected families and set up a phone line for parents to call if they have any questions. It said no child's health is in danger.
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