Abstract: At approximately 10:30 a.m. on December 5, 2006, employees were working in a call center building, and one employee complained about the odor of natural gas. Management did some tests but found nothing. Shortly after, other employees complained of lightheadedness, chest pain and nausea. At approximately 11:30 a.m. an employee was taken to the medical clinic which prompted management to call the Fire Department. The ambulance came and took 10 employees to the hospital, meanwhile, the building was evacuated and the Hazmat team started testing for Hydrogen Sulfide, Carbon Monoxide, Oxygen level and any hydrocarbon present. Nothing was found. Later, the Hazmat team said it was safe for employees to come back. The employees taken to the hospital were given series of tests including EKGs, heart monitoring, blood tests, and oxygen level tests. The tests were all negative so they were all sent home. Inspection was conducted the following day. The affected area was located on the far-end wall, right of the entrance door of the building and was within 15 ft to 20 ft of the employees work stations. The affected employees were interviewed and four of the employees were definite about the smell of the natural gas, one employee was not sure, and one employee alleged a sulfur-like smell, like a burnt wire which he smelled for approximately 5 seconds and then it was gone, but the employee said it was definitely nothing like a gas or exhaust fume smell. The incident resulted in no employee injury.