A review of the latest IoT-enabled fire door monitoring systems. Can technology finally solve the persistent problem of wedged-open or damaged fire doors in residential blocks?. Smart Fire Doors: IoT Monitoring for Assured Compliance and Safety The ubiquitous fire door, a seemingly simple yet profoundly critical component of fire safety, has long been a weak link in the chain of passive fire protection. From being wedged open by residents to suffering damage through everyday wear and tear, their integrity is constantly under threat. However, a new wave of Internet of Things (IoT) enabled monitoring systems is emerging, promising to revolutionise how these vital safety features are managed and maintained. These smart solutions offer real time insights into the status of fire doors, moving beyond reactive inspections to proactive, continuous assurance, and potentially solving the persistent problem of non compliant or compromised fire doors in residential and commercial buildings across the UK. Background The devastating fires at Grenfell Tower and other high rise residential buildings brought into sharp focus the systemic failures in fire safety, particularly concerning passive fire protection elements. Fire doors, designed to compartmentalise a building and resist the passage of fire and smoke for a specified period, are paramount to occupant safety and evacuation strategies. Their failure can lead to rapid fire spread, trapping residents and hindering firefighter operations. Current regulatory frameworks, such as the Regulatory Reform (Fire Safety) Order 2005 (RRO 2005), place a clear duty on responsible persons to ensure adequate fire safety measures are in place and properly maintained. This includes regular inspections of fire doors. However, these inspections are often periodic, typically annually or bi annually, leaving significant gaps during which a door's integrity can be compromised. The Building Safety Act 2022 (BSA 2022) further strengthens these requirements, particularly for higher risk buildings (HRBs), introducing more stringent duties for building owners and managers, and empowering the Building Safety Regulator (BSR) to enforce compliance. The BSR's Gateway 2 and 3 processes demand robust evidence of fire safety measures throughout a building's lifecycle, making continuous monitoring an increasingly attractive proposition. Traditional fire door maintenance relies heavily on visual inspections, often carried out by trained professionals. While essential, these inspections are snapshots in time. A door compliant today could be wedged open tomorrow, or its self closing device could fail next week. This inherent limitation creates a significant risk gap, especially in multi occupancy residential buildings where tenant behaviour can directly impact fire safety. The Approved Document B (ADB) to the Building Regulations provides guidance on fire safety, including requirements for fire doors, but the practical challenge lies in ensuring these requirements are met and sustained in operational buildings. Key Developments The advent of affordable and robust IoT technology is now addressing this gap. Smart fire door systems typically involve small, discreet sensors attached to the door frame, leaf, and sometimes the closer mechanism. These sensors can detect a range of critical parameters: Door Position: The most fundamental function is to detect whether a door is open, closed, or ajar. This immediately flags if a fire door is being propped open, a common and dangerous practice. Door Closure Speed: Sensors can monitor the speed at which a self closing door returns to its frame. A slow closure could indicate a failing closer mechanism, while an excessively fast closure might suggest damage or misalignment. Door Integrity/Damage: Accelerometers or impact sensors can detect unusual impacts or forced entry attempts, potentially indicating damage to the door leaf or frame that could compromise its fire resistance. Environmental Factors: Some advanced systems incorporate temperature and humidity sensors, which can provide early warnings of environmental conditions that might affect door materials or performance over time. Usage Patterns: By logging every opening and closing, these systems can provide valuable data on door usage, informing maintenance schedules and identifying high traffic areas where accelerated wear and tear might occur. Data from these sensors is transmitted wirelessly, often via low power wide area networks (LPWANs) like LoRaWAN or NB IoT, to a central cloud based platform. Building managers and responsible persons can then access this data through a dashboard, receiving real time alerts for any non compliance or detected fault. This enables immediate intervention, whether it's sending a maintenance team to repair a faulty closer or addressing an occupant who is repeatedly propping open a door. Leading manufacturers are integrating these capabilities into comprehensive building managemen