Inspected Guest Rooms #117, 212, 302, 304, 310...DISCUSSION: Water supply lines on all ice machines did not appear to have a double check valve (backflow preventer). Backflow prevention shall be in place where required to prevent contamination of the water supply inlet. The plumbing system shall be repaired according to law and maintained in good repair...Observed at least three spray bottles with yellowish liquid inside labeled as quaternary ammonium sanitizer or Oasis 146 sanitizer but no sanitizer was available in laundry room. Remember that sanitizing solutions shall not be stored in or dispensed from containers previously containing poisonous or toxic materials. All cleaning agents such as bleaches, detergents, and polishers shall be used and stored according to manufacturer's recommendations on labels.