Faint echoes of sirens sounded seconds before a low-toned horn noise blasted from the roof of Allison Hall on Tuesday morning. Some passers-by looked up briefly for the source of the sound. Shortly after, a voice boomed from speakers: “This is a test of the Northwestern warning system. This is only a test.”

The siren is one of the university’s recent efforts to improve emergency warning systems on campus, and comes less than two months after a former student shot and killed five students at Northern Illinois University.

Sirens will sound on the first Tuesday of every month at 10 a.m., when the municipal outdoor warning systems in Illinois are tested, and follows an initial test last Thursday.

“It went well last week, and it went well this week,” said Charles Loebbaka, the director of university media relations. “So, the test was successful.”

Juliana Farley, an Allison resident and a Communication freshman, said she is glad to see the testing taking place, but thinks she and other students may be bothered by the 10 a.m. alarm, clearly heard inside the dormitory

The sirens sounded from speakers mounted on the roofs of four campus buildings, according to a press release: Allison Hall, the Donald P. Jacobs Center, Tech and Harold Anderson Hall. A non-emergency message followed the siren.

The system is in place to alert those who may be outdoors when a campus emergency occurs. Students, faculty and staff will also be notified through telephone, e-mail and text messages.

Alexandra Petrakos, a Weinberg freshman and a resident of Allison Hall doesn’t think the alarm will bother students. She views the tests as necessary “so that in case of an emergency everyone can be alerted properly.”

“The only way that they can make sure that everything is being kept up properly is if they test it every month,” Petrakos said. “I think it’s for the best.”