Longtime mechanics know what they can get away with and what they cant as far as safety equipment goes. Some cannot.
As a preemptive strike to injury we decided to do a safety basics so that we can introduce at least a moderate sense of safety while wrenching on your van or bus. There are some areas that a bit of foresight might suggest a little forethought. Usually people will think to use a jackstand when under a car on a jack, but not always.
I was working at a bodyshop in Alhambra California when one day a seasoned tech used a scissor jack to lift a car near the front tire. He had welded a nut onto the threaded rod of the scissor jack so an impact would lift it fast. It was lighter than the floor jacks we used and easy to move around. It was however not as stable. He was trying to adjust a fender gap in a questionable manner when I noticed the car swaying back and forth, and his hand was under the pinchweld of the rocker.
Before anyone could say much of anything the car fell on him. he quickly pulled his hand out from the rocker and looked at his hand. The ends of his fingers were already turning blue and he was lucky it pinched the ends of his fingernails. He very nearly lost his fingers on his right hand because he was trying to save a few seconds of work.
Use a jackstand when you are working on a car. As a bodyman since the beginning of the 90’s I have worked on countless cars, and I have taken risks with jacks and stands, but they were very calculated risks. I would suggest not taking even calculated risks to be on the safe side.
It only takes a few seconds to slide a jackstand under a frame or suspension component. Pull up on the top and the racheting action will take it as far up as you can go. Lower the jack slightly to preload the jackstand, you don’t want a falling car to hit the stand and kick it out. Ive seen this plenty of times too. Preload some weight on the stands if at all possible.
All the stands in the world might not help if the car is not in park or in gear with the brake set. If this isn’t possible chock the wheels so it wont roll. Doing both might be the best option as well. The more level the ground is the better.