Start with the smallest oyster
Write down the smallest shell size entering the bag and the size range expected before harvest or grading. A nominal mesh number alone cannot show whether the bag will retain that stock.
Define the measurement convention
“Mesh size” may refer to the clear gap, a nominal aperture or spacing measured between strands. State the method, units and tolerance on the drawing, and check the result on a sample.
Account for mesh pattern and handling
Square and diamond patterns can present different openings when the mesh is stretched or loaded. Confirm the pattern and how the bag will be held, filled and inspected.
Verify with a representative sample
Before ordering a production quantity, compare the measured opening with the retention target and the farm’s water-exchange and cleaning needs. Keep the approved sample or marked drawing as the reference.
QUICK CHECKLIST
- Smallest shell size to retain
- Square or diamond mesh pattern
- Clear-opening or other agreed measurement method
- Tolerance and sample-approval procedure