Roof Top Unit - under Zone of Protection

[Ranger86]

NFPA 780 (2011 edition), section 4.8.10.3 reads, " at least 2 main-size conductors shall be installed to connect the unit to the lightning protection system ". If the RTU is under a zone of protection, does this section still apply ?

 

[david luchini]

NFPA 780 (2011 edition), section 4.8.10.3 reads, " at least 2 main-size conductors shall be installed to connect the unit to the lightning protection system ". If the RTU is under a zone of protection, does this section still apply ?

See the text of 4.8.10.

 

[Ranger86]

4.8.10 talks about strike termination devices. It is not clear to me if section 4.8.10.3 applied only if it is not located in a zone of protection. So basically, what you are referring to (I assume) is that if it is under a zone of protection, then none of 4.8.10.1 thru 4.8.10.3.2 apply. Is this correct ?

 

[david luchini]

4.8.10 talks about strike termination devices. It is not clear to me if section 4.8.10.3 applied only if it is not located in a zone of protection. So basically, what you are referring to (I assume) is that if it is under a zone of protection, then none of 4.8.10.1 thru 4.8.10.3.2 apply. Is this correct ?

Yes. 4.8.10 says that strike termination devices shall be required...on all rooftop mechanical units with continuous metal housings less than 3/16" thick...that are not located in a zone of protection.

 

[Ranger86]

Thanks for your help.