What knee pads to you use?
Not quite "Safety" but that's the closest fit.
What knee pads do you find both comfortable and practical?
I guess a couple of different types are in order - soft and hard - wouldn't want to be up on a roof in hard jobbies because of the slipping danger.
I have a pair of Irwins with a hard shell but the damn things like to move around on my legs a fair bit, so I don't wear them much.
For many tasks I use a pillow case that I have several sheets of 3mm neoprene in so it's about an inch thick. Excellent for gardening and many other floor jobs because of the large surface area.