Which of the following covers lightning protection systems and defines as exposed anything above ground and outside the zone of protection?

NTSB-12 is not a recognized standard for lightning protection systems - NTSB is the National Transportation Safety Board and does not publish electrical grounding or lightning standards.

IEEE 1100 is the Recommended Practice for Powering and Grounding Electronic Equipment (the Emerald Book) and does not define lightning protection zones or exposure classifications.

NFPA 780, the Standard for the Installation of Lightning Protection Systems, provides comprehensive requirements for designing and installing lightning protection, including the definition of the zone of protection. It classifies any object above ground that falls outside this protected zone as exposed, meaning it is vulnerable to a direct lightning strike.

NEC 47 is not a valid or recognized standard designation in the context of lightning protection - the National Electrical Code addresses lightning in Article 230 and 250, not a standalone 'NEC 47.'

ANSI J/STD-607-A is the Commercial Building Grounding and Bonding Requirements for Telecommunications standard and does not cover lightning protection zone-of-protection definitions.