Roofers several stories up, trying to batten down their materials during high gusts. (Photo: Jan Thomas)

The trees outside my office window are being blown by a “fresh breeze,” fall leaves whipping off.  The local weather station reports 18 to 20 mph gusts.  Last night I watched a Weather Channel report on workers in Japan being blown about by typhoon-generated winds of more than 85 mph.  All this reminds me that I’ve been meaning to write a blog on how to determine when windy conditions are safe for workers, cranes, and other outdoor material handling.  I’ve seen plenty of guys trying to carry sheets of plywood during high wind.  And, I really get concerned when the unloaded crane hook is swinging in the breeze.

I’m always being asked, “What’s OSHA’s rule on wind speed?”  That’s easy – there is NO general rule.  In fact, current OSHA General Industry and Construction standards say very little other than a few minor mentions in outdated crane standards.  That will change when OSHA finally adopts the new Subpart CC – Cranes and Derricks in Construction. (You saw that right – OSHA’s going into double alpha for their subparts.)

For example, proposed §1926.1417(h) states “when a local storm warning has been issued, the competent person shall determine whether it is necessary to implement manufacturer recommendations for securing the equipment.”  Suddenly, we have at least 3 entities that can help us make a decision – the National Weather Service, the on-site competent person, and the crane manufacturer!   The conditions of each crane pick are different and do depend upon on-site decisions.  Several sources, too numerous to list here, indicated that by the time wind gets to 20 – 25 mph it is getting too risky to operate cranes.

And, what about those workers lifting plywood and other materials on the roof?  When should they be concerned?  This should be obvious, but sometimes not to the supervisor tucked away in the office.  Check out the Beaufort Scale for land wind conditions.