Do Not Open Sign

Do Not Open Sign

The Do Not Open sign is a prohibition notice used aboard vessels to warn crew and passengers against opening a door, hatch, panel, or enclosure that could expose them to a hazard if disturbed. It is typically fixed directly to electrical cabinets, watertight doors, access panels, or compartments where opening the cover could reveal live wiring, pressurised lines, or restricted machinery. On merchant ships and offshore installations this sign is mounted at eye level on the item it protects, so crew see the warning before attempting access, reinforcing the isolation procedures required under shipboard permit-to-work systems.

As an ISO 7010 pictogram, the artwork shows a black hand pressing against a panel, enclosed within a red circle and diagonal bar on a white background, the universal graphical language for prohibition signage recognised across international fleets regardless of a crew member’s first language. The design corresponds to IMPA code 33.8560 and ISSA code 47.585.60, the reference numbers ship chandlers and marine equipment suppliers use when sourcing safety signage for a vessel’s compliance inventory. Safety Sign Hub keeps this pictogram in stock and ready for despatch, so procurement officers can order exact replacements without describing the symbol from scratch.

Where This Sign Is Fitted On Board

The Do Not Open sign is most commonly fitted to switchboard covers, junction boxes, emergency generator enclosures, and access hatches leading into confined or pressurised spaces. Engine room crew rely on it to identify equipment that should only be opened by an authorised technician following lock-out procedures, reducing the chance of an unqualified crew member exposing themselves to arc flash or trapped energy. Deck officers also use the sign on stores lockers or chemical cabinets where the contents are hazardous if disturbed by untrained personnel. Because the pictogram needs no translation, it works equally well on vessels crewed by multiple nationalities, and many operators standardise it across sister ships so every crew member recognises the same warning wherever they are assigned.

Every Do Not Open sign supplied by Safety Sign Hub is produced from fire-retardant, UV-stable material engineered to withstand the corrosive salt-air environment found on deck and in engine spaces. The pictogram is printed using durable inks that resist fading from prolonged sun exposure, and a photoluminescent variant is available for compartments where lighting may fail during an emergency, keeping the prohibition symbol visible for a period after power loss. Panels are manufactured to standard ISO dimensions so they align with the rest of a vessel’s signage suite, and the printed surface resists the diesel, hydraulic fluid, and cleaning chemicals common around machinery spaces, so the sign stays legible for years rather than needing early replacement.

This Do Not Open sign is held in stock as a self-adhesive vinyl label for direct application to a flat panel or door, and as a rigid polypropylene or aluminium panel for surfaces needing a more permanent fixing with screws or rivets. Both formats share the same pictogram artwork and IMPA/ISSA reference, so a chief officer restocking a vessel’s safety signage can simply quote the SKU or code when placing a repeat order. For fleets managing signage across several vessels, browsing the full range of prohibition signs makes it easy to build a consistent shipboard package in one order.

Meeting Recognised Signage Standards

Specifying pictograms that align with the ISO 7010 graphical symbol standard, as detailed at iso.org, gives fleet operators confidence that signage is understood consistently across ports and flag states. Because the same graphical convention underpins Australian Standard AS 1319 for workplace safety signs, vessels calling at Australian ports benefit from displaying prohibition symbols that shore-based surveyors and stevedores already recognise from onshore industrial sites. Maintaining this consistency across a fleet also simplifies crew inductions, since new crew transferring between vessels encounter the same symbol language instead of relearning ship-specific conventions each time they join.

When planning a signage refit, check existing Do Not Open signs during each annual survey, since UV exposure and repeated washdowns can dull the printed red and black contrast crew rely on for quick recognition. Superintendents preparing a pre-survey checklist often batch-order replacement pictograms alongside other prohibition and mandatory signs so a single delivery covers the whole list, reducing freight costs and avoiding delays if a surveyor flags worn signage. Keeping spare panels in the bosun’s store means a damaged sign can be replaced immediately rather than waiting on a shore order.