Hundreds of US colleges and universities have purchased an instructional aid for their staff which offers advice on how to react in the event of a school shooting.

The guide, produced by a commercial organisation called the Centre for Personal Protection and Safety, suggests that, in an “active shooter” scenario, lecturers should make use of the “inherent strength in numbers” on the side of shooting victims.

The training programme includes footage of a gunman opening fire in a classroom full of students amongst its teaching materials. Advice issued to school staff includes using a laptop or book as an “improvised weapon” against an assailant armed with a gun.

Domenick Brouillette, a course instructor, tells his clients to “look at your environment through the lens of survival.

“Survivors prepare themselves both mentally and emotionally to do what it takes. It might involve life-threatening risk. You may do something you never thought you were capable of doing.”

As the programme’s publicity material states, “the odds of being involved in an 'active shooter' situation are similar to being struck by lightning. But lightning does strike, and active shooter situations happen, and when they do the results are catastrophic.

“While organizations and law enforcement agencies have revamped their prevention and response strategies to address this critical issue, history shows that the immediate action of people on the scene is the most effective way to minimize or stop the violence."

Self-defence classes of various kinds, particularly targeted at women, have played a role in campus security at US institutions for decades; however, this is thought to be one of the first initiatives specifically dealing with school shootings.

In August of this year, US President George W. Bush signed into law amendments to the Jeanne Clery Act, tightening the legislation which forced universities to inform students of potentially dangerous situations as soon as possible.

The 2007 Virginia Tech shooting, in which Seung-Hui Cho killed 33 people in two separate incidents several hours apart, led to criticism of university security and the manner in which authorities dispense information.

In the aftermath of the massacre—the United States’ deadliest—officials experienced a leap in applications for concealed firearms licences from students, who expressed the desire to protect themselves with hidden weapons on campus and in classes.

The first documented school shooting in the United States took place in 1966, when Charles Joseph Whitman murdered 17 people at the University of Texas at Austin from the observation deck of a 32-storey building.

Since the 1999 Columbine High School massacre, in which 15 people died, school shootings have become a yearly occurence in the USA, with multiple fatalities in every subsequent year.