GARLAND, Texas (CBSDFW.COM) – Students in the Rio Vista Independent School District in southern Johnson County spent their first full day at home Wednesday after a flu outbreak forced the closure of all campuses.

A massive cleaning operation is underway to remove germs before students return to the classroom next week.

In Garland, ServiceMaster, a commercial cleaning company which has a lot of experience sanitizing schools, gave CBS 11 a look at the weapons they use in the war against germs.

A fogger is among the tools the company uses on schools that have been contaminated with a virus like flu.

The chemical spray disinfects the air while industrial strength cleaning powders are mixed with water to wipe all over every single chair, table, wall, floor and ceiling.

Tom Johnson, of ServiceMaster North Texas, demonstrates chemical spray used to disinfect schools. (CBS 11)

Tom Johnson, of ServiceMaster North Texas, said it can take up to 100,000 gallons of cleaning solution and 10 to 15 people to cover an entire school.

Johnson said when it’s finished, kids in schools like the ones in Rio Vista ISD should have a healthy environment.

“It’s a 100% effective if it’s done correctly,” said Johnson. “Shut it down for a couple of days, do a deep clean get everyone healthy and then the school is safe to go.”

Johnson says by the time children are back in school the detergents in the cleaning solutions will have evaporated and shouldn’t pose any health risk.

Rio Vista ISD officials have said their work crews will be conducting a thorough cleaning during the next two days.

Rio Vista Elementary School (CBS 11)