04/02/2013 03:50 am ET

Colorado Marijuana DUI Bill Advances, THC Blood Level Limits Cleared For A Vote By The Full House

A Colorado House committee advanced a bill to set marijuana blood limits for drivers Monday.

House Bill 1114, also known in previous years as the marijuana DUI bill, would say that drivers are legally impaired if their blood contains more than 5 nanograms of THC per milliliter. THC is the psychoactive ingredient in marijuana.

In February, the state's 24-member marijuana task force endorsed the bill meant to mirror the drunk driving limit of .08 blood alcohol content except for one significant exception: drivers would be able to argue in court that they are not impaired at the 5 nanogram limit.

Three previous attempts to set a marijuana blood limit for drivers, including one just last year, failed in the state Senate and one of the bills' most contested aspects has been the actual limit itself. Opponents have argued that a person's size, tolerance and other factors have an effect on whether or not 5 nanograms of THC would cause driving impairment. Frequent users, like medical marijuana card holders, can surpass that limit even if they haven't been smoking recently.

"I haven't had a car accident since I was 18, and I've had marijuana in my system for most of that time," said marijuana activist Paul Saurini, 39, in a report by The Washington Post.

The bill however is cleared for a vote by the full House that could happen as early as this week.

Meanwhile in Washington, the other state that voted to legalize marijuana, some have argued that the 5 nanogram limit is still too low for a DUI standard.