Yes, you should speak with a personal injury attorney. The failure to provide the railings, or to take other reasonable precautions, may constitute negligence and entitle your father to some compensation. Note, however, that compensation is linked to the severity of injuries and the extent of any monetary losses or costs incurred; if your father escaped with "just" some bruising and pain, but no permanent injury or disability, no significant medical costs, etc., it may not be economically worthwhile to bring a legal action.