Monitored by Detector Sign

Monitored by Detector Sign – IMO A.654(16) Fire Control Symbol FS0249

This Monitored by Detector sign identifies a space or item of equipment that falls within the coverage of the vessel’s fixed fire detection system, confirming that heat, smoke or flame in this location will trigger an automatic alarm. The pictogram shows the standardised red chevron within a circle, matching exactly what appears on the vessel’s fire control plan for this location. As SKU FS0249 in the Fire Fighting Signs range, it is designed for permanent fixing in machinery spaces, accommodation areas, cargo holds and other compartments covered by automatic fire detection.

A “monitored by detector” marking confirms to crew and surveyors that a space is under continuous automatic surveillance for fire, which makes fast, confident identification of detector coverage critical during fire control plan reviews, system testing and genuine incident response. Clear signage also supports routine fire equipment rounds, where crew confirm detector coverage remains intact and unobstructed in line with the vessel’s approved fire safety design. The photoluminescent background of this sign keeps the marking identifiable during a blackout, exactly when confirming detection coverage may be part of assessing where a fire has been contained.

Why Monitored by Detector Identification Matters

Crew and surveyors both need to confirm at a glance which spaces are covered by automatic fire detection, whether reviewing the fire control plan during a drill or verifying coverage during a class survey. Correctly signed detector zones also support fire safety inductions, helping new crew understand which areas are under continuous monitoring and which may require additional vigilance or manual checks. This distinction matters particularly in machinery spaces and cargo holds, where automatic detection is often the first line of defence before a fire is visible or detectable by crew on rounds.

Compliance and Certification

This sign reproduces the fire control symbol set derived from IMO Resolution A.654(16) and continued under the current ISO 17631 standard for fire control plan graphics, matching what flag-state surveyors and classification societies expect to see identifying detector-monitored spaces. SOLAS Chapter II-2 sets requirements for fixed fire detection and alarm systems covering machinery spaces, accommodation and cargo areas, and correctly labelled coverage markers are part of demonstrating that this system is genuinely in place during Port State Control inspections and class surveys. Fitting SKU FS0249 keeps your fire detection signage matched to the fire control plan surveyors will reference.

Installation Recommendations

Fix this sign at the entrance to or within the monitored space, using the pre-drilled fixing holes for a permanent mechanical fixing or the self-adhesive backing on smooth painted surfaces. In machinery spaces and cargo holds exposed to vibration, heat and oily residue, a screw or rivet fixing will outperform adhesive over the vessel’s operating life, and the sign should remain visible even when other equipment is temporarily stowed nearby. Check the sign periodically during routine fire equipment rounds to confirm it remains legible and correctly reflects the space’s current detector coverage.

• Standard IMO/ISO 17631 fire control symbol – red chevron in circle detector coverage pictogram
• Photoluminescent base for visibility during blackout or power failure
• 150x150mm rigid or self-adhesive format to suit steel, aluminium or GRP surfaces
• UV-stable, corrosion-resistant construction for machinery space and cargo hold use
• Matches fire control plan symbols exactly for fast, confident equipment identification

Order the FS0249 Monitored by Detector sign to keep every detector coverage zone on your vessel clearly identified before your next drill or inspection. Safety Sign Hub stocks the complete IMO fire control symbol range and ships marine-grade signage across Australia and to vessels in port.

Browse the full Fire Fighting Signs range for every fire control plan symbol your vessel needs, or see our Hazard Signs for ISO 7010 warning pictograms to complete your safety signage programme.