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Apprentice answer

Should seismic restraint cables have slack in them

3rd YearSeismic Bracing & Vibration ControlCheck first

Seismic cables should restrain movement without pulling the duct out of line. Remove sloppy slack and adjust them per the approved seismic detail.

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Plain-English answer

A loose seismic cable lets the duct swing before the cable catches it. That momentum can shock-load anchors, rods, and other trades.

Check the approved seismic layout, cable direction, anchor points, and whether tightening the cable pulls the main hangers out of plumb. Adjust to the required condition and document for inspection.

Ask Foreman

The seismic cables on [run/location] have visible slack. I checked the brace direction and rods. Do you want them tightened per detail before inspection?

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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