A CHANCE decision to take a day off from work yesterday probably saved the life of a Shekkipmei Hongkong Bank teller. Cheung Pui-yee is one of 17 staff who work at the small branch office which mostly serves residents of the nearby old-style housing estate. Instead of enjoying her extended weekend, 23-year-old Ms Cheung spent the day helping police identify her unconscious colleagues at the Caritas Medical Centre in Shamshuipo. She had been resting at home when she heard news of the incident on television and rushed to the hospital. ''I know many of the people injured in this accident, I just came to see the conditions of my colleagues,'' said Ms Cheung. Not realising her daughter had taken a day off, Ms Cheung's mother had also rushed to the hospital. She was so relieved when she found her daughter safe that she hugged her for a long time. Three other staff who normally work at the branch also escaped possible injury yesterday by being away from their office. One male staff member was attending a course, while a female teller was on maternity leave. A female amah who works on the afternoon shift also escaped injury.