Our driver was unloading Hydrochloric Acid when EE went up trailer ladder (approx. 4-5 feet) to disconnect air supply hose. EE disconnected the hose, vapor and some product came out and EE dropped the hose to the ground. Product continued to leak out of the hose and EE hurried down the ladder to stop the leak. EE missed the last rung and fell to the ground, fracturing right heel.