a hair washing unit for washing the hair of bedridden patients is formed as a unitary , hollow , rotationally moulded shell . the shell has a peripheral wall surrounding a central recessed well . a u - shaped depression in a front part of the wall merges smoothly into a shoulder support ramp sloping outwardly from the front of the unit to support the shoulder and neck area of a person whose hair is being washed . a drain opening from the well into the shell interior provides for waste water storage and transportation within the shell , while a second drain from the shell provides for disposal of the waste water .