We are preparing to convert an existing bathroom to a handicapped access bathroom. It will entail tearing out the bathtub, and installing a roll-in shower. The house is on a slab, so we'll have to get into the concrete to move the drain to the proper location and slope the surrounding concrete floor to the drain. We'll be using ceramic tile on the bath and shower floor.

My question is this; On a slab floor like this with nothing underneath, is it necessary to use the standard "mud pan" shower liner that goes up the walls, under the floor and into the drain? If so, what is the recommended installation procedure?

Thanks for your help.

"My question is this; On a slab floor like this with nothing underneath, is it necessary to use the standard "mud pan" shower liner that goes up the walls, under the floor and into the drain? If so, what is the recommended installation procedure?"

No! What you're doing, in effect, is installing a floor drain that a "roll in" shower will set over and drain via a indirect waste.
You may use a shower drain and a trap or a regular floor drain with a built in trap. Note: A floor drain does not require a vent.
Good luck, Tom