Signs shall not resemble, imitate, or approximate the shape, size, form, or color of railroad or traffic signs, signals, or devices. Signs shall not obstruct or interfere with the effectiveness of railroad or traffic signs, signals, or devices. Signs shall not be erected, relocated, or maintained so as to prevent free ingress to or egress from any door, window, or fire escape; and no sign shall be attached to a standpipe or fire escape. Signs shall not be placed so as to obstruct or interfere with traffic visibility, nor be lighted in such a way as to cause glare or impair driver visibility upon public ways.