Set up and preparation
The most common plaster systems used today are called veneer or skim-coat plasters. Falling under the general category of drywall systems, they consist of one or two coats of thin plaster over sheets of special gypsum board. This gypsum board, also known as blueboard, is basically the same as standard gypsum board except it has a different paper surface designed for greater moisture absorption and bonding with plaster. The blueboard is available in 1/2-in. and fire-code 5/8-in. thicknesses and comes in standard drywall dimensions.
Our crew doesn't install the blueboard, so prior to starting any plaster work; we check the installation to ensure that all the panels are tightly fastened. Protruding or loose screws that missed the framing are corrected. The panels should be tight to each other, and electrical boxes should be inset. We then cover the subflooring with tarps and protect all of the windows and the doors with painter's plastic and masking tape. If plaster were to get on any wood, glass or metal surface, it would clean off easily, but it's better to keep it off in the first place.
Blueboard that has been faded by ultraviolet light should be treated with either an alum solution or plaster bonding agent only if a lime putty plaster is applied directly to the board. With a two-coat system this is not a concern because the base coat is gypsum which will adhere just fine.