No Thoroughfare Sign

No Thoroughfare Sign

Some passageways, decks and gangways aboard a vessel are safe to stand in but never safe to walk through, whether because of overhead lifting operations, restricted transit during cargo work, or a route that leads directly into a hazardous machinery space. A no thoroughfare sign tells crew, passengers, stevedores and visiting contractors that a route which might otherwise look like a normal walkway is closed to foot traffic, without relying on a written notice that not every reader will understand.

Like every sign in the ISO 7010 prohibition series, this no thoroughfare sign uses a red circular band with a diagonal bar over a black pictogram of two walking figures, set on a white background. The universal graphic means a no thoroughfare sign is recognised instantly by seafarers of any nationality, port authority inspectors, and shore labour working cargo operations, which is essential on multinational crews and in Australian ports handling vessels from dozens of flag states.

Typical Locations for This Prohibition Sign

Common placements include gangways during cargo transfer, decks beneath suspended loads, walkways adjacent to open hatches, restricted zones around mooring winches under tension, and passageways temporarily closed for maintenance or hot work. AS 1319 calls for prohibition signage to be positioned at the point of decision, meaning a no thoroughfare sign should be mounted where a person would otherwise choose to proceed, such as at the foot of a gangway or the entrance to a blocked alleyway, rather than further along the closed route.

Safety Sign Hub produces this no thoroughfare sign in a rigid, fire-retardant photoluminescent material that absorbs ambient or emergency lighting and re-emits a visible glow for an extended period after lights fail. During a blackout, fire, or emergency drill, a glowing no thoroughfare sign remains readable exactly when crew are relying on signage to navigate safely and avoid walking into an area that has become newly dangerous.

Ordering by IMPA and ISSA Code

Ship chandlers and marine procurement teams generally specify signage by catalogue code, and this no thoroughfare sign corresponds to IMPA 33.8503 and ISSA 47.585.03. Referencing either code when raising a purchase order removes any doubt about pictogram, size and material when restocking a vessel, outfitting a new build, or supplying a shore-based terminal with matching signage.

Safety Sign Hub supplies this no thoroughfare sign to Australian shipowners, ship managers, stevedoring companies and port facilities that need to control pedestrian access around active cargo and lifting operations. For general guidance on workplace safety signage obligations in Australia, see Safe Work Australia. A clearly positioned, photoluminescent no thoroughfare sign is a simple, low-cost control that helps prevent a routine transit turning into a serious incident.

Because pedestrian routes on a working vessel can change from shift to shift, having a ready stock of this no thoroughfare sign on board lets the duty officer close off a walkway the moment a hazard is identified, rather than waiting for signage to be sourced ashore. Keeping spares in the bosun’s store alongside other prohibition and warning signs is standard practice on well-run vessels and helps ships pass port state control inspections without signage-related deficiencies being raised.

Sign placement should also account for line of sight in poor weather, since fog, rain and heavy deck lighting glare can all reduce the distance at which a printed notice is legible. Positioning a no thoroughfare sign at a consistent height across every deck and gangway, rather than wherever a convenient bulkhead happens to be, helps crew scan for it instinctively during busy cargo watches. Many ship managers standardise mounting height and sign size across their whole fleet for exactly this reason, so a new crew member transferring between vessels already knows where to look and what the pictogram means before they set foot aboard.

Browse our full range of prohibition signs for more IMO-compliant maritime safety signage.