My understanding is that if it is worn as a sash (across one shoulder) it indicates an injury. I don't remember what it means when worn as a belt, but I don't think it's bad...
If worn during the day, it alerts cadre that the basic is on a Form 18 for some injury or illness. During low light conditions, it will be worn so that people are visible (the AF is concerned about pedestrians getting run over),
the blue belt means they may not be able to do everything the other basics will be doing. it just lets the cadre know so they dont push them to far... as far as road guards are concerned, they got new orange vests this year