The term “readily available” is not defined in 1910.151; however, according to a April 18, 2002 Letter of Interpretation, OSHA says that the person who has been trained to render first aid must be able to quickly access the first aid supplies in order to effectively provide injured or ill employees with first aid attention. The first aid supplies should be located in an easily accessible area, and the first aid provider generally should not have to travel through several doorways, hallways, and/or stairways to access first aid supplies.