. >> i know folks get ansi. there is a state of emergency in effect, where folks aren't supposed to be out on the roadways anyway. stay home, enjoy your family, enjoy your friends. please don't drive. >> and, obviously, still cloudy conditions out here in maryland. we haven't seen the sun at all today. it hasn't stopped snowing once since we have been out here. we can tell you as the sun goes down and the conditions get a little darker, this snow, if it keeps blowing around is going to make visibility more difficult, so even more reason to stay off the roads if at all possible. reporting live, 9news now. >> all right, thanks so much. let's take a look at the beltway right now. this is the capital beltway in prince georges county. this is video shot earlier when conditions were worse. near whiteout, and you look at the signs there. blizzard conditions, stay off the road. blizzard conditions, stay off the road. we were talking to transportation officials, saying it's the first time they can remember putting up sig

. >> i think the ansi standard is below the threshold we have to keep track of how many times you go through the screening process at the airport. >> anyone else? >> i spent most of my career working in radio activity and radiation physics we have been involved in many years of working with regulatory agencies in being involved in the health-a dose effect relationship. how accurately can you measure the radiation? the health effects as regulated by the food and drug administration and osha and the regulatory commission. the federal guidance in this country for health effects comes from the national council on radiation protection and measurements. those offices follow that guidance. this is not coming out of nist or tsa. there is an american national standard and i think this is a great example of the cooperation here. there were four members from nist and members from different parts of dhs and two from tsa. that is the standard for the safety aspects of the deployment of these x-ray scanners. many folks are pushing for the military -- millimeter wave scanners. there are no radiatio

coursey, correct me if i'm wrong but i think the ansi standard is 24,000 microrim per year.my career at nist working in group there so nist has been involved for many years in working with the regulatory agencies on dose health effect relationships. but the nist measurement sciences is how accurately can you measure the radiation. the health defects as regulated by food and drug administration and osha and the nuclear regulatory commission. so there's -- the federal guidance in this country for health effects comes from the national council on radiation protection and measurements. and those of us in the federal agencies follow that guidance. so this is not guidance coming out of nist or tsa. there's an american national standard 4317 which was developed -- and i think this is a great example of the cooperation here because it had four members from nist. seven from different parts of dhs. two from fda who actually participate in writing that standard. and that's the standard for the safety aspects of the deployment of these x-ray scanners. i might also point out that a lot o