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Apprentice answer

Why is an un-set drop-in anchor dangerous for duct hangers

1st YearHangers, Supports & AnchorsStop and get direction

An un-set drop-in anchor is an overhead failure waiting to happen. Pull the rod, set or replace the anchor correctly, and verify it before loading duct.

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Plain-English answer

Threading rod into a drop-in anchor does not mean the anchor is set. The internal plug has to be expanded with the proper setting tool before the hanger can carry load.

If one is missed, assume nearby anchors may need checking too. Back out the rod, set or replace the anchor by the approved method, and do not lift duct until the hanger line is verified.

Ask Foreman

This hanger anchor at [location] was threaded but does not look set. I stopped loading the run. Do you want every anchor in this section checked and reset/replaced before we lift duct?

Verify before acting

Use this as training guidance. Foreman direction, approved drawings, project specs, manufacturer instructions, employer safety policy, and AHJ/code requirements always control the final answer.

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