While OSHA does not explicitly require employers to have safety signages in more than one language, OSHA requires that safety training must be clear and unambiguous so that employees can easily understand new information presented to them. In a 2009 study, it was found that Hispanic employees who had trouble speaking English were at more risk of injury due to language barriers.
If you decide to add Spanish safety signs in your workplace, TRADESAFE recommends that you develop multilingual awareness training not only for your Hispanic employees but also for all employees. Even if safety signs are made to be self-explanatory, it still helps to conduct training about them to ensure everyone understands them.