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SOLAS II-2/7: Fixed Detection vs IR

By Engineering — Compliance · May 3, 2026 · 6 min read

Draft SOLAS II-2/7 amendments require portable IR thermal imagers for container-deck hot-spot screening. On vehicle decks, portable is the wrong unit.

IMO sub-committee work has produced draft amendments to SOLAS regulation II-2/7 requiring portable infrared thermal imagers for screening containers and detecting hot spots. The provision is sensible for containerships, where crew can walk the bays. On enclosed vehicle decks the same approach hits a wall.

Where portable detection works

  • Container stacks accessible from walking paths between bays.
  • Deck cargo with line-of-sight from external walkways.
  • Scheduled inspection rounds with crew time to operate the imager.

Where portable detection fails

  • Vehicle decks parked bumper-to-bumper, three deep — most surfaces are not accessible to a hand-held imager.
  • Belowdeck spaces with restricted crew access during voyage.
  • Continuous coverage requirements — a portable imager is by definition not continuous.

The fixed-detection argument

A regulatory floor that requires portable imaging on vehicle decks would be a paper exercise — present on the equipment list, absent at the moment a thermal event develops. Fixed, per-vehicle detection meets the underlying intent of the draft amendment. We expect the next round of IMO deliberation to clarify the distinction.

Portable detection is a complement to fixed detection on container decks. On vehicle decks it is a placeholder. The regulation will catch up.

Sources

  • IMO — SOLAS regulation II-2/7 (fire detection and alarm) and the draft amendments on portable thermal-imaging equipment for cargo hot-spot screening.
  • IMO Sub-Committee on Ship Systems and Equipment (SSE) — work programme on detection of fires in cargo and vehicle spaces.
  • IMO MSC.1/Circ.1638 — ro-ro space fire-safety guidance.
  • [VERIFY: exact session and document symbol of the draft II-2/7 portable-imager amendment — confirm against the latest SSE/MSC report before publication.]
Frequently asked

Questions, answered

What do the draft SOLAS II-2/7 amendments require?+

Portable infrared thermal imagers for screening containers and detecting hot spots. The provision is sensible for containerships, where crew can walk the bays with a hand-held imager on scheduled rounds. On enclosed vehicle decks the same approach hits a wall.

Why is portable thermal imaging the wrong unit of analysis on a vehicle deck?+

Vehicles park bumper-to-bumper, three deep, so most surfaces are inaccessible to a hand-held imager; belowdeck spaces have restricted crew access during the voyage; and a portable imager is by definition not continuous. Requiring it on vehicle decks would be a paper exercise — present on the equipment list, absent when an event develops.

Does fixed detection satisfy the intent of the draft amendment?+

Yes. Fixed, per-vehicle detection meets the underlying intent — continuous hot-spot screening — that portable imaging only nominally provides on a vehicle deck. The expectation is that the next round of IMO deliberation will clarify the distinction between container decks and vehicle decks.

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