In the video clip at the bottom of this post, you'll see polyurethane being used to seal air leaks in new manholes before they were vacuum tested. I was on this "do or die" job as a consultant. Apparently they had been having trouble with the first type of product they tried.

I remember stepping out of my truck and being greeted by our customer with the words, "I don't wanna' hear can't! I don't wanna hear won't! We gotta make this work!" Based on my experience working with polyurthane, I wasn't too worried. It all worked out in the end and the manholes passed the vacuum seal tests. Take a look at the video for an overview of the polyurethane leak seal process...

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