ABC News on Campus reporter Charlie Litton blogs: Colorless, tasteless and odorless might well describe some of the food options available at college campuses around the nation, but a far more serious danger carries the same attributes. Last month, students at the University of Nebraska-Lincoln learned just how dangerous when members of a fraternity living in their house began suffering headaches and nausea. Then they suffered dizzy spells and some even fainted. After a call to 911, rescue responders determined the cause was a carbon monoxide leak, and quickly ferried 42 students to a local hospital. All were later released with no apparent serious side effects. Similar stories can be found across the nation, and all have a common theme. Without monitors, the only way to know of a carbon monoxide leak is to suffer the symptoms of poisoning. With a monitor, the sensor generally goes off before any symptoms appear. Last year, a residence hall at Harvard was evacuated when a carbon-monoxide leak set off sensors. In 2007, 23 Virginia Tech students were hospitalized—five critically poisoned—by a similar leak in an off-campus apartment complex (without monitors). In the latter instance, all recovered, but three young women spent more than a week in the hospital. Carbon monoxide is a result of combustion, and so most leaks are a result of poor ventilation associated with gas fireplaces, furnaces, and other gas appliances. In the case at Virginia Tech, the cause was traced back to faulty ventilation for the heating element in a hot water heater, according to police. At Harvard, a strong downdraft caused by stormy weather apparently stopped a fireplace from exhausting fumes properly, Adams House Master John Palfrey told the Harvard Crimson, after the Cambridge police and fire departments were called to the scene. In Nebraska, the cause was also faulty ventilation, this time from the building’s furnace, according to the Lincoln Fire Department. All residence halls in Nebraska are equipped with electric appliances, so there is no need for carbon monoxide detectors in those buildings, said UNL’s interim housing director Sue Gildersleeve said. But Greek housing falls outside of UNL housing authority, so detectors are not required. About 10 fraternities have since added monitors. Just 24 states require carbon monoxide detectors in certain residences, but only eight only require them in newer buildings, and two others do not include large apartment complexes in their statutes. Texas’ requirement is limited to day-care facilities and homes, while Virginia law allows a tenant to install a monitor if they feel it’s necessary. Virginia law also forbids a tenant from tampering with a monitor installed by a landlord, but does not mandate they install one in the first place. CO monitors, though, are not all created equal. According to Consumer Reports, the detectors can range from $30 to over $100. Some are not sensitive enough, while others will sound an alarm even if the CO levels are well below dangerous levels. And because CO is invisible to human perception, the only thing to do is evacuate and call the fire department. However, as the EPA notes, any CO monitor is better than no monitor at all — something all students should consider before signing a lease.