What this is
What is a trailer and equipment inventory?
What is a trailer and equipment inventory?
A register listing every trailer, container and piece of transport equipment currently on site: unit number, owner, arrival date, free-time expiry, condition and current position. It is maintained continuously, so the site can say with certainty what it is holding and for how long.
Who owns the register?
The yard controller, supported in practice by gatehouse and dock staff who see equipment arrive and leave. It is only correct if every arrival and release is entered close to the event; batching updates once a shift lets it drift from reality within hours.
How is it different from a gate log?
The gate log is a stream of movement events, one row per vehicle crossing the gate. The inventory is a snapshot of what is currently on site: a trailer can sit for weeks generating no gate activity while still needing to appear on the inventory.
Scope
When is a trailer and equipment inventory required?
The inventory is one step in the Yard and Gate Control programme. Using it to record a single movement, a physical walk or a billing dispute produces a register that cannot be trusted as the current picture of the yard.
Use this template when
- A trailer, chassis or container arrives on site and needs to be added to the register
- An existing entry needs its status, position, condition or free-time information updated
- A unit is released or retired and needs to leave the active register
- The site is reconciling what it holds against a physical count of the yard
- A downstream record, such as a detention dispute or an empty equipment release, needs this entry to already exist
Do not use it for
- Yard Check Record, which walks the yard and records what is actually parked where against what the register believes.
- Gate Entry and Exit Log, which records the individual vehicle movement, not the equipment's ongoing presence.
- Dock Schedule Adherence Review, which assesses schedule performance, not what equipment is sitting where.
- Detention and Demurrage Log, which turns the dwell figures this register produces into a billing or dispute record.
- Lease-return condition surveys, which need a full interchange-standard inspection rather than the single Condition field here.
Compliance mapping
Which Contract requirements requirements does this satisfy?
There is no single regulator for a trailer inventory. Its defensibility rests on three frameworks: US detention-billing rules, intermodal interchange practice, and the roadability standard equipment must meet before it moves again.
| Clause | Requirement | Where it lands |
|---|---|---|
| FMC interpretive rule on demurrage and detention (46 CFR Part 545) | Detention and demurrage invoices must reflect that the invoiced party had a reasonable opportunity to retrieve, return or mitigate the charge | Register health |
| Shipping Act s.41102(c) / s.41104(a)(10), as amended by the Ocean Shipping Reform Act 2022 | Prohibits unjust or unreasonable detention and demurrage practices, including inadequate notice or documentation | Register health |
| 49 CFR 396.17 | Intermodal equipment subject to periodic inspection confirming roadworthy condition before further movement | Equipment on site |
| Uniform Intermodal Interchange and Facilities Access Agreement (UIIFA) practice | Condition and custody recorded at the point of transfer, forming the basis for later condition disputes | Equipment on site |
| IICL-9 interchange condition criteria | Container and chassis condition graded against a defined criteria set rather than an unstructured description | Equipment on site |
| Contract detention and free-time terms (carrier or lessor agreement) | Free time and per-diem rate are fixed by the individual agreement and must be reflected per unit, not assumed uniform | Equipment on site |
What it does not cover
- Yard Check Record, the physical walk that verifies the register against what is actually parked in the yard.
- Gate Entry and Exit Log, the record of the individual vehicle movement, including driver and cargo detail this register does not capture.
- Detention and Demurrage Log, which turns a dwell figure into an actual invoice, dispute or settlement record.
- The interchange receipt itself, the signed document transferring custody and condition responsibility at gate-in and gate-out under UIIFA-type terms.
- A full condition or damage survey, which a lease return or insurance claim needs conducted against IICL-9 or equivalent criteria.
Global
Trailer and Equipment Inventory requirements by country
Detention regulation is concentrated in the United States; elsewhere defensibility rests on contract and interchange standards rather than a dedicated statute.
FMC interpretive rule on demurrage/detention (46 CFR Part 545); Shipping Act as amended by the Ocean Shipping Reform Act 2022
Carrier billing practices for detention and demurrage must give the invoiced party a reasonable opportunity to act, and invoices must be adequately documented.
Accurate arrival, free-time and dwell data is the primary evidence a site has to dispute a charge that fails the reasonableness test.
Common-law penalty rule (Cavendish Square Holding v Makdessi, 2015)
No dedicated detention statute; a per-diem clause is enforceable only if it protects a legitimate commercial interest and is not extravagant against that interest.
A register showing genuine cost and disruption from a unit's dwell supports the argument that the charge reflects real loss, not an unenforceable penalty.
UIIFA-type interchange agreements; IICL-9 condition criteria
Equipment condition and custody are established at the point of interchange under industry-standard terms, independent of any national regulator.
This register is the site-side complement to the interchange receipt, not a substitute; a condition dispute is argued from the receipt first and the register second.
How to complete it
How to complete a trailer and equipment inventory, step by step
The fields exist to hold a status. Whether the register is defensible when a charge is disputed depends on judgement the fields alone do not enforce.
Days On Site is only as accurate as the Arrival date behind it. Pulling Arrival from the gate log or interchange receipt at the moment equipment is dropped, not backfilling it when someone notices the unit, keeps the dwell figure trustworthy enough to argue a detention position from.
Free time varies by carrier, lessor and sometimes commodity. A default figure applied across the register produces a Beyond Free Time flag right for some units and wrong for others, and wrong in both directions is worse than simply missing.
Register Reconciled To A Physical Check exists because the register drifts from reality between reconciliations. A cadence tied to the Yard Check Record, not an ad hoc walk when something looks wrong, is what catches the equipment nobody logged.
Good, Fair and Poor mean nothing to a carrier or lessor disputing a return unless anchored to something, such as IICL-9 grading criteria. An unanchored score records an opinion, and opinions do not survive a condition dispute.
What auditors find
Most common trailer and equipment inventory findings
The register almost always exists and is almost always populated. The findings concern whether it reflects the yard as it actually stands.
| Finding | Clause | What fixes it |
|---|---|---|
| Register not reconciled to a physical count on any set cadence. | Contract detention terms | Schedule reconciliation against the Yard Check Record and record its Check ID each cycle. |
| Days On Site calculated from an assumed date rather than the actual arrival event. | FMC interpretive rule (46 CFR Part 545) | Source Arrival from the gate log or interchange receipt, not a manual estimate entered later. |
| Free Period Expires blank or set to a uniform default rather than the unit's actual contract terms. | Contract detention terms | Enter free time from the specific carrier or lessor agreement at the point the unit is logged. |
| Condition scored without reference to a defined criteria set, producing inconsistent grading between entries. | IICL-9 interchange condition criteria | Score Condition against a stated criteria set and note deviations, rather than a bare impression. |
| Estimated Detention Exposure not maintained as dwell accrues, so an invoice arrives with no comparable internal figure. | Shipping Act s.41104(a)(10) (OSRA 2022) | Update the exposure figure as Days On Site changes, not only on receipt of an invoice. |
| Owner left blank while the unit continues to accrue dwell against the site. | UIIFA interchange practice | Require Owner at entry; treat an unresolved owner as a blocker to release, not a detail for later. |
Case in point
Case in point: the reefer nobody knew was theirs
A distribution site received equipment from several carriers on a busy corridor. A refrigerated trailer arrived after the yard controller's shift ended, was dropped at an open dock by an unrecognised driver, and the gate log recorded only the tractor leaving empty. No inventory entry was made, because nobody connected the departing tractor to a trailer left behind.
The reefer sat against a wall for eleven weeks before a yard reconfiguration uncovered it. By then the carrier had invoiced for detention from the day of arrival using its own records, and the site had no entry, no dwell figure and no free-time position to weigh the invoice against. The fix was not a stricter field; it was making the physical drop, not gate exit, the event that creates an entry, so a dropped unit cannot go off the books simply because nobody watched it arrive.
The template
The template, field by field
The form exactly as it installs. Every field, option, score and conditional rule is editable, and the links to other templates come with it.
3 sections
- Reference
- LOG-021
- Archetype
- Register
- Record ID
- TRLR-2026-000
- Scoring
- Equipment dwell time
- Direction
- High is bad
- Singleton
- Yes
- Basis
- Contract requirements
- Links
- Feeds Detention Log and Empty Equipment Release
- Tags
- Yard, Registry
- Sections
- 3
- Fields
- 34
- Follow up fields
- 3
- Repeating sections
- 1
- Links out
- 4
Header
8 fieldsRegister ID*
Auto sequence. Format TRLR-2026-000.
The record's own ID. Other templates point at this value.
Status*
Drives who this goes to next.
- Planned2 pts
- In progress2 pts
- Complete3 pts
- Deferred0 pts
- Open0 pts
- Closed3 pts
- Overdue0 pts
Last Reviewed*
Maintained By*
Next Review Due*
Site*
Site ID*
Format SITE-000.
Links to FDN-001 Site ID
Detention Accrues Against What You Forgot
Charges run against equipment nobody knew was still here. A live register is the only defence, and it is the thing most sites keep on a clipboard in the gatehouse.
Equipment on site
Repeats12 fieldsUnit Number*
Unit Type*
Owner
Arrived*
Free Period Expires
Days On Site*
Loaded Or Empty*
- Yes2 pts
- No0 pts
- N/Aexcluded from denominator
Current Position*
Seal Number
Condition*
- Good3 pts
- Fair1 pt
- Poor0 pts
Beyond Free Time*
- Yes2 pts
- No0 pts
- N/Aexcluded from denominator
Release Requested
- Yes2 pts
- No0 pts
- N/Aexcluded from denominator
Register health
14 fieldsUnits On Site*
Units Beyond Free Time*
Longest Dwell Days*
Estimated Detention Exposure
Register Reconciled To A Physical Check*
- Yes2 pts
- No0 pts
- N/Aexcluded from denominator
Check ID
Links to LOG-020 Check ID
Action Required*
Raise the action record, then enter its reference here.
- No2 pts
- Yes0 pts
Priority
- High0 pts
- Medium1 pt
- Low3 pts
CAPA ID
Format CAPA-2026-00000.
Links to FDN-014 CAPA ID
Action Owner
Yard Controller*
Signature*
Logistics Manager*
Second Signature*
LOG-021 · record IDs look like TRLR-2026-000 · Feeds Detention Log and Empty Equipment Release
Open in KnowellaRun it with agents
From a document you fill in to a programme that runs itself
The register is straightforward to fill in. What fails is the surrounding discipline: the arrival nobody logged, the free time nobody entered, the reconciliation that never happened.
Holds the register against gate and check records, flags entries with no recent reconciliation, and routes overdue units to the yard controller.
Tracks condition and roadability findings against the register so a unit flagged Poor is not returned to interchange without review.
Watches dwell against free-time expiry across the register, raises detention exposure before it reaches an invoice, and holds every write for approval.
This template lives in KnowLogistics — supply chain execution. Inbound, outbound, inventory, yard, claims, supplier lifecycle and customs.
Glossary
Trailer and Equipment Inventory definitions and key terms
- Free time
- The contractual period equipment may remain on site before per-diem or detention charges accrue against it.
- Detention
- A per-diem charge levied by a carrier or lessor for retaining their equipment beyond the agreed free time.
- Dwell time
- The elapsed time a unit has been present on site, calculated from arrival; the register's core metric.
- Interchange receipt
- The document recording condition and custody when equipment is transferred between carrier and site, under UIIFA-type terms.
- Roadability
- The condition standard, covering tyres, brakes, lights and structure, equipment must meet under 49 CFR 396.17 before returning to interchange.
FAQ
Frequently asked questions about trailer and equipment inventory
Does the register replace the interchange receipt?+
No. The interchange receipt is the signed document transferring custody and condition responsibility at the gate. The register is the site's ongoing record of what it currently holds, built from those receipts but not a substitute for one.
How is Days On Site calculated correctly?+
From the actual arrival event, sourced from the gate log or interchange receipt, not from when someone happens to notice the unit. An estimated arrival date produces a dwell figure that will not survive a detention dispute.
Who is liable when the register is wrong?+
Practically, the site, because an unlogged unit is invisible to the yard controller's own detention position. The carrier's own records do not disappear simply because the site failed to log its side.
What should trigger an entry: the gate event or the physical drop?+
The physical drop. Equipment can be left at a dock without a distinct gate event for the trailer itself, particularly when a tractor detaches and leaves separately, so tying entry creation to the drop closes the most common gap.
How often should the register be reconciled to a physical count?+
On a set cadence tied to the Yard Check Record, not only when a discrepancy is suspected. Drift accumulates between reconciliations regardless of how carefully entries are logged day to day.
Is this a singleton, and what does that mean here?+
Yes. One continuously maintained register per site, holding many equipment rows, rather than a separate record per unit or event. Other templates, including the Detention Log, refer back to it.
Keep going
Related templates and programmes
Industries this is written for
Programmes this belongs to
Used together in Yard and Mobile Plant
Yard Check Record
Walks the yard and records what is actually parked where against what the system believes
Gate Entry and Exit Log
Records every vehicle entering and leaving, who was driving, what they carried and whether they were expected
Dock Schedule Adherence Review
Reviews how the dock schedule performed against plan, covering slot adherence, turnaround and idle doors
Empty Equipment Release
Releases an empty trailer, container or pallet load of equipment back to its owner and records the condition it left in
Detention and Demurrage Log
Records time a vehicle or container spent beyond its free period, why, and who is liable
Loading Dock Safety Check
Checks dock levellers, edge protection, lighting, restraints and pedestrian separation before and during loading
More in Yard and Dock
Yard Check Record
Walks the yard and records what is actually parked where against what the system believes
Gate Entry and Exit Log
Records every vehicle entering and leaving, who was driving, what they carried and whether they were expected
Dock Schedule Adherence Review
Reviews how the dock schedule performed against plan, covering slot adherence, turnaround and idle doors
Empty Equipment Release
Releases an empty trailer, container or pallet load of equipment back to its owner and records the condition it left in
Written and reviewed by
Siddarth Singh
Founder & Chief Executive Officer, Knowella
Certified Safety Professional and industrial and systems engineer with more than a decade inside food supply chain, freight and manufacturing operations. This page was written against the current text of the standards it cites, not against secondary summaries of them.
- Certified Safety Professional (CSP), Board of Certified Safety Professionals
- MBA, University of Chicago Booth School of Business
- MS and BS, The Ohio State University, Industrial and Systems Engineering
- Six Sigma Black Belt
Sources and last review. Reviewed 16 August 2026 against:
- FMC interpretive rule on demurrage and detention practices, 46 CFR Part 545
- Shipping Act of 1984, s.41102(c) and s.41104(a)(10), as amended by the Ocean Shipping Reform Act of 2022
- 49 CFR 396.17, periodic inspection of intermodal equipment
- IICL-9 interchange condition criteria (Institute of International Container Lessors)
This page is general guidance, not legal advice. Confirm requirements with your jurisdiction’s regulator.