Lisa: here's 1 web (many more on the subject) explaining how to install grab bars, might help
How to Locate Bathroom Grab Bars | eHow.com - [ Traducir esta página ]6 May 2010 ... They should be placed parallel to the floor on a reinforced wall ... The side grab bar should be 42 inches long and the rear bar ... Place a 12-inch long grab bar on the wall behind the drain, 33 to 36 inches above and ... grab bars are pulled free of their supports while being gripped by a bather. ...
www.ehow.com/how_6050454_locate-bathroom-grab-bars.html