Why this matters
Use this leader guide before setting blocks, shims & glazing pinch zones work to review the real setup, the controls that need to be in place, and the conditions that should stop the task. Installation work often combines awkward positioning, temporary support, drilling/fastening and hidden conditions. The job is safe only when the substrate, support method, fastener/anchor plan and nearby utilities are verified before the load is released.
A scenario to discuss
The crew performing Setting Blocks, Shims & Glazing Pinch Zones has the component supported and nearly in position when the field condition does not match the drawing, scan, backing, or planned attachment point. What must be supported, lowered, or rechecked before improvising a connection?
Before work starts
- Verify substrate/framing/blocking, the specified fastener/anchor and any manufacturer requirements before loading the assembly.
- Locate concealed electrical/plumbing/other services before drilling or cutting.
- Set temporary support/lifting aids and stage tools/fasteners so nobody has to improvise while holding the load.
- Plan where the lite will land and position setting blocks/shims before hands are trapped under the glass.
- Use suction devices or mechanical aids within their ratings and keep backup control until the lite is stable.
Common failure points
- Assuming the wall/substrate is suitable without verifying framing, blocking or anchor conditions.
- Removing temporary support before the required fasteners are fully installed and checked.
- Drilling/cutting into concealed conditions without a utility/hidden-condition check.
Safe work sequence / controls
- Plan where the lite will land and position setting blocks/shims before hands are trapped under the glass.
- Use suction devices or mechanical aids within their ratings and keep backup control until the lite is stable.
- Use non-hand tools for final alignment when practical instead of placing fingers in narrow glazing pockets.
- Do not release support until stops, beads, clips or other retention are installed as required.
Stop and reset the plan if...
- The substrate, framing/blocking or anchor/fastener condition is not what the plan assumed.
- Temporary support shifts, the load cannot be controlled, or a fastener spins/pulls out/fails to seat as expected.
- Drilling/cutting encounters an unexpected void, metal, wiring, piping or other concealed condition.
Questions worth asking the crew
- What substrate, framing, backing, or support is actually behind the finished surface, and how did we verify it?
- How will the component/load be temporarily supported while the first connections or fasteners are installed?
- What fastener, anchor, or connection is planned, and what field result would tell us the connection is not taking the load as expected?
- What concealed electrical, plumbing, mechanical, or structural condition could be in the drilling/cutting path, and how are we checking for it?
- Has anyone discovered bad backing, a hidden service or a fastener that would not hold during a similar installation? What check would catch it earlier here?
Make it real on the job
Show the actual substrate/fastener/support method and the drilling path before the first hole is made.
Close the talk
Before the crew starts, everyone should be able to explain the hazard, point to the control being used today, and name the condition that would make the work stop.
Related authoritative reference
OSHA 29 CFR 1926.250 - Material Handling · Open reference ↗
This is a practical discussion guide, not a substitute for required training, a competent person, permits, manufacturer instructions, employer procedures, or applicable federal/state/local requirements. Adapt it to the actual task and conditions.
