What information should accompany a thickness enquiry?
Describe the complete panel assembly, not just a sheet size. Use separate dimensions for the cut panel and the opening it covers, and show where the panel is supported. For a replacement, supply the available drawing or material identification and explain any changes to the process since it was fitted.
- Reach prevention
Show the relationship between the guard, any openings and the hazardous movement. Include access from the side, above and below; panel thickness alone does not describe these routes.
- Splash or process debris
Identify the liquid or material, its direction and temperature, and the cleaning products used. Keep a splash-control requirement distinct from a claim that the assembly can contain an ejected part.
- Potential impact or ejection
Provide the available hazard information, panel span, frame details and retention arrangement for a competent engineering assessment. Do not select a thickness from a different machine solely because the panels look similar.
There is no universal safe thickness.
A stated millimetre value is not a complete guarding specification. The possible impact or ejection, distance from the hazard, unsupported span, frame stiffness, fixings, edge detail, allowable deflection and environmental exposure all affect selection.
A polycarbonate panel behaves as part of an assembly. Increasing thickness can alter stiffness and resistance, but performance also depends on panel width and height, how far the edges overlap the frame, hole positions, fastener details and whether loading is concentrated or spread across the surface.
Questions to resolve before specifying the panel.
- What part, tool or material could strike the panel, and with what mass, speed, shape and direction?
- What are the panel dimensions and unsupported span?
- How stiff is the frame, and how are the edges and fasteners retained?
- Is the duty reach prevention, splash control or impact containment?
- Which temperatures, UV exposure, cleaners, coolants, oils or process chemicals are present?
- How will scratches, crazing, damage and ageing be detected during inspection?
Thickness is only one design variable.
A thicker sheet cannot compensate for weak support, unsuitable material grade or poor fixing details. Large panels behave differently from small panels of the same grade and thickness. Hole clearances, edge distances, thermal expansion and local stress all need to be considered as part of the complete assembly.
Where impact containment is important, the hazard data and an appropriate engineering method, evidence or test basis should support the selection. The old machine window can provide useful background, but it is not proof that its material, grade or thickness remains adequate after changes to tooling, speed or process.
Related guidance.
Compare transparent materials in the polycarbonate versus acrylic guide, review signs of deterioration in the panel inspection guide, or read about the survey and installation process.
Technical note: guarding and material decisions must follow the specific machinery, environment and a suitable risk assessment.