“Light” and “heavy-duty” help organise a product range, but they are not a complete specification. When you compare plastic dust sheets, look for measurable details and a clear explanation of the work each pack is intended to handle.
Understand a thickness figure
Plastic thickness may be expressed in microns. One micron is one thousandth of a millimetre, so 15 microns is 0.015 mm. That conversion explains the unit; it does not establish the thickness of an unmeasured product.
A thickness claim should belong to the exact SKU or pack you are buying. Do not borrow a number from a similar-looking carton, an older design or another pack in the same brand.
Thickness is also only one part of the specification. A number alone does not prove puncture resistance, slip resistance, suitability for walking on or performance with a particular liquid.
Match the stated use
For a simple furniture cover, easy positioning and enough material to drape around the item may matter most. Where the work involves more handling, ask what the manufacturer's heavy-duty description actually covers.
Read the limits alongside the benefits. Look for guidance about sharp edges, rough surfaces, dragging, reuse and wet work. If a claim is vague, ask for clarification rather than filling in the missing detail yourself.
Compare like for like
Make a short comparison with four rows: sheet dimensions, sheets per pack, verified thickness if available, and intended use. Keep price on a separate line so a large pack does not look stronger simply because it costs more.
Choose the product whose documented use matches your task. Treat a missing thickness figure as missing information, not a value to estimate from the photograph or packaging colour.