I've never seen anything resmbling a figure for 'safe separation' for a
lightning stroke. Lighting comes in a variety of sizes, all potent,
all unpredictable. I suspect its an unanswerable question....
>>ANYWAY, i can put in the tables, if interested, sample:
>>kV (working BIL (kv) Clearance to
> conductors people roads
>>7.5KV 95 6" 7" 8 ft 20 ft
>>Now i will ASSume everyone on this list understands that 7.5 KV sparkover is
>>A LOT less than 6" <grins>, with the 6" providing working margin for
>>95 KV surges, lightning, or other...
>But I do question their 8' gap for 'people' and 20' for roadways. Is
>the road more sensitive to a lightning strike than a person?;)
The standard implicitly (explicitly???) covers overhead clearance from
wires, busbars, etc, foo, mumble.
8' for people allows 6' high people plus 24" margin.
20' for roadways allows 18' high trucks plus....
(6ft and a smidge...)