Table 1.
Size categories of plastic marine litter, assuming a near-spherical form, showing common definitions and alternative options that may be appropriate for operational reasons from [36].
| Field Descriptor | Common Size Divisions |
Measurement Units | Alternative Options |
Remarks |
|---|---|---|---|---|
| Mega | >1 m | meters | ||
| Macro | 25–1000 mm | meters centimeters millimeters |
25–50 mm 1–25 mm |
|
| Meso | 5–25 mm | centimeters millimeters |
<25 mm |
MARPOL Annex V (pre-revision) |
| Micro | <5 mm | millimeters microns |
1–5 mm <1 mm >330 μm |
[37] |
| Nano | <1 μm | nanometers | <100 nm | Not considered for monitoring |