On Saturday 11 April 2009 08:31:55 Joe Greco wrote:
Speaking of that, a manhole cover is typically protecting some hole, accessway, or vault that's made out of concrete.
An oxyacetylene torch or a plasma cutter will slice through regular steel manhole covers in minutes.
Yes, but we were discussing locked covers, which (given the underlying assumptions of this discussion) might be a bit heavier. Further, it would be vaguely suspicious and more noticeable for a "road crew" or "power company" truck to be deploying such gear, might draw more attention.
The locking covers I have seen here put the lock(s) on the inside cover cam jackscrew (holes through the jackscrew close to the inside cover seal rod nut), rather than on the outside cover, thus keeping the padlocks out of the weather.
More expense. :-)
One way of making a site more resistant to 'inside job' issues is with SCIF- like controls (see http://en.wikipedia.org/wiki/Sensitive_Compartmented_Information_Facility ) and using combination locks such as the Sargent and Greenleaf 8077AD for control, and the S&G 833 superpadlock for security (see http://www.sargentandgreenleaf.com/PL-833.php ). The tech would have the 833's key, and the area supervisor the combination. The 8077AD's combination is very easily changed in the field, and could be changed frequently. The key to this method's success is that the keyholder to the 833 cannot have the combination, and the holder of the combination cannot have an 833 key. Requires a certain atmosphere of distrust, unfortunately. And slows repairs way down, especially if the 833's key is lost....
Certainly it is *possible* to do it, but given the other variables, does it make *sense*? Consider what I was saying about just going to town with a backhoe. You have a lot to protect. ... JG -- Joe Greco - sol.net Network Services - Milwaukee, WI - http://www.sol.net "We call it the 'one bite at the apple' rule. Give me one chance [and] then I won't contact you again." - Direct Marketing Ass'n position on e-mail spam(CNN) With 24 million small businesses in the US alone, that's way too many apples.