A three foot area around the panel needs to be clear so that there is easy access to the panel. The National Fire Protection Agency Standard is as follows: Sufficient space shall be provided and maintained about electric equipment to permit ready and safe operation and maintenance of such equipment. Where energized parts are exposed, the minimum clear work space shall not be less than 6½ feet high or less than 3 feet wide. In all cases, the work space shall be adequate to permit at least a 90 degree opening of doors or hinged panels. 1999 National Fire Protection Agency 70, Article 110-32