The Shipper's Guide to NMFC Rule 170:
The 96" Vertical Rule
In 2025, carriers are increasingly using automated laser dimensioners to inflate freight density by capturing "air." If your pallet is marked 'Do Not Stack', Rule 170 dictates that the density must be calculated based on the full vertical clearance of the trailer—typically 96 inches—regardless of your actual pallet height.
The Auditor's Trap
A 48-inch tall pallet at Class 100 becomes a Class 250 reclassification the moment an auditor applies the 96-inch vertical override. Without a Sentinel Deterministic Certificate, you have no documented proof to rebut a $500+ overcharge on a single pallet.
The 2025 Calculation
When you mark a shipment as non-stackable, the carrier loses the ability to put another pallet on top of yours. Under NMFC 100-series rules, they are entitled to bill for that "lost" vertical capacity.
Total Cubic Feet = (Length x Width x 96") / 1,728
Actual Density = Weight / Total Cubic Feet
Result: Lower PCF = Higher Class = Increased Invoice
How to Rebut a Rule 170 Violation
Winning a dispute in 2025 requires more than just a photo. Carriers require deterministic evidence generated at the time of pickup:
- 1.Capture timestamped dimensions via Sentinel.
- 2.Apply 'Do Not Stack' cones to the top surface.
- 3.Generate a Sentinel PDF citing Rule 170 overrides.
- 4.Physically attach the certificate to the pallet face.
Equip Your Warehouse.
Stop reclassifications at the source. Download the high-resolution reference sheet for your shipping team to use during palletization and audit defense.
Free Resource • Authenticated by Sentinel Network