You should install grab bars behind and alongside the toilet. The Americans With Disabilities Act specifies that grab bars around the toilet should be 33 to 36 inches off the floor. If your toilet isn't enclosed, consider installing a grab bar that mounts on the floor and wall on the side of the toilet that's open.
A shower stall for someone who is disabled should be open to allow easy access, especially if the user has a wheelchair. Install at least two grab bars. They should be 33 to 36 inches off the floor. An alternative is one horizontal bar and another vertical bar. The shower should also have a seat.
Likewise, a bathtub should have at least one wall-mounted grab bar so that the user can easily enter and exit the tub. The grab bar should be 33 to 36 inches off the bottom of the tub.
The bar mounted behind a toilet should be at least 36 inches in length, while the bars mounted at the sides of the toilet should be at least 42 inches long. Shower stall bars should be at least 18 inches long. In a bathtub, the bars should be at least 24 inches long.