Precautions when living with shy dogs

I keep an opened corralling pen in front of my front door. It not only slows the dogs down if they decide to bolt, but it also reminds me that I must take my time when leaving the house. My dogs stay in the house when I'm at work. Even well-adjusted dogs can get freaked out by a thunderstorm or a car backfiring and either jump the fence or dig under. I always walk my dogs on either a slip leash or martingale collar. Once again, even a non-skittish dog can get spooked and slip a regular collar. In my opinion, regular collars are for holding ID (and left on at all times) and martingales are for walking.