http://wkbn.com/2017/04/10/local-firefighters-concerned-over-plywood-ban/ (http://wkbn.com/2017/04/10/local-firefighters-concerned-over-plywood-ban/)
It is no longer legal to cover doors and windows of vacant buildings with plywood in Ohio.
It still is, as long as you are not a bank owning a foreclosed property.