K7LXC@aol.com wrote:
> For many construction and engineering purposes, a wind is only worth
> considering when it reaches 70 MPH. And the TIA-222 windspeeds are every 50
> years occurrences.
It might be worth clarifying a point about the '50 year occurances'... This
'50
year' period is called the return period, or sometimes recurrence interval. It
is
a means of expressing 'exceedance probability'. Unfortunately, it is frequently
misunderstood to mean that one and only one '50 year' event will occur during
those 50 years.
Actually, what it all really means is that the probability of the 50 year wind
being exceeded is 1/50 in each year. In other words, it's quite possible to
experience back to back '50 year' events in the same year. All this is another
way of saying ... Follow the LXC 'Prime Directive' or do what the manufacturer
recommends.
--
73, Pat K7KR
List Sponsor: Champion Radio Products - We'll be at the Dayton Hamvention
with all of our safety equipment and other products. Stop by booth #559 and
say hi.
<A HREF="http://www.championradio.com";>www.ChampionRadio.com</A>
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