Fall protection proprietary system anchorage to metal roof deck

[TedEP]

Who has experience with the anchorage of a fall protection proprietary system to metal roof deck?

I am working with a manufacturer, Guardian, with their system "XS Horizontal Lifeline system". I was provided the design load by their engineers. The load is 3,600 lbs applied horizontally to the top of a 8 1/4" post. Their system provides the anchorage of the post to the metal deck (in my case 20 ga wide rib roof deck) via their "toggle fastener".

Their sales literature says the load is "so slight", but I dont consider 3,600 lbs slight. I can easily check the roof framing for the load, but the localized effects of the load on the metal deck is not so easy, especially in the weak direction. I'm sure the manufacturer verified the ability of steel decks to sustain that type of load through full scale testing, but they are not offering it for DOR's use.

I'm sure I'm not the first one to challenge their system's anchorage scheme. What am I missing?

Thanks for your input.

 

[steellion]

It won't work. It needs to be anchored into a structural component. They will say that their design stops at the bottom of their post. Providing a system below the deck to support the loads for the fall protection system typically falls in the EOR's scope from my experience.

 

[bhugey]

Strong agreement here - your gut is correct. Yes, provide steel framing and appropriate detail for attachment. Define clearly who is responsible for attachment to structure. Plan location of anchors is typically going to be a coordination issue - locations determined by architects or possibly by supplier. Contractor in the end needs to coordinate anchor locations with framing.
Best of luck

 

[zcp]

Design your deck to handle the load. Put in local supports as needed. Push for the test results. Generally you can get them.

Check out the lines in their spec in section 1.05. We generally try to be stronger than the threaded rod and then understand that insulation will crush / deck will deform / etc. to dissipate energy.

Hope that helps.

ZCP

http://www.phoenix-engineer.com

 

[KootK]

I checked out the product literature. I'll give them high marks for innovation. However, I would derive little comfort from knowing that somewhere there was a human being prevented from plummeting to her death be a puddle weld or a Hilti pin loaded in tension.

The greatest trick that bond stress ever pulled was convincing the world it didn't exist.

 

[MrHershey]

We typically provide steel (either hot-rolled or cold-formed) blocking underneath and screw directly to it so we don't have to worry about the deck taking the load.