It's a little ridiculous for me to be doling out advice about cold and ice -- I grew up in California. But the NorCal hippie in me has to say something:
Please, don't use salt to melt the ice on your sidewalk.
So, what is safe to use? Let's turn to a city that knows cold (and, btw, has a Capitol Hill of its own). Denver suggests kitty litter or sand. Here's an interesting discussion of the effectiveness for both options.
If you only have salt around the house (my predicament tonight), better to make things safe than not. But try to pick up a bag of litter the next time you are out and about.