This is a simple and plain explanation of the permanency of fumigation cover:
A Fumigation Cover: Durability.
The quality of a fumigation cover largely hinges on the quality of the material, GSM, UV proof and the treatment it is subjected to. In general:
Lifespan Expectancy (Indian Use)
Type of cover Approx. durability.
Light HDPE / PE (120-150 GSM) 1-2 years
Heavy HDPE Laminated(170-200 GSM) 2-4 years.
Fumigation Cover of PVC Coated Fumigation Cover (400-500 mic / Premium) 5-7 years.
Industrial PVC HF-Welded Seam 7-10 years.
PVC fumigation covers have the greatest durability as they are airtight, and they also resist UV and tearing and weather damage compared to HDPE.
What Is So Durable about a Fumigation Cover?
Airtight quality – should have ability to retain gases without leakage.
UV stabilisation – eliminates cracking due to sunlight.
Large GSM / thickness – increased tear and puncture resistance.
Heat welded seams – there are no holes and it is stronger.
Weather resistant – can withstand heat, rain, moisture.
Durability Reducing Factors.
Dragging on rough surfaces
Folding while wet
Extensive exposure to direct sunlight.
Spillage of sharp objects / grain slicing the sheet.
Poor workmanship (rather than welding)
How to Increase Durability
Never drag, but always raise the sheet.
Fold and store in a dark place.
Clean dust and grains used.
Patch or heat weld but do not stitch up small holes.
and be of proper size–larger sheets are torn more quickly.
Practical Summary
A good fumigation cover, particularly the type made of PVC can last 5+ years with good care. Grain markets (mandi, rice mills, warehouses) Basic HDPE covers last 1-3 years with handling.
I can describe, too, should you desire:
Optimal fumigation cover material.
GSM recommendation
Price comparison
Fumigation covering applied in rice mills (Hanuman Trading Co.)
Just tell me!