Fire Detection Latency, Coverage and Cost Cannot All Improve Together
Compare detection platforms on three numbers and the pattern is always the same. In-situ sensors — a gas or heat node on a pole, a detector on a ceiling — can call a fire within seconds, but only where one was installed, so coverage costs money linearly. A camera tower watches tens of kilometres in every direction for minutes-to-detect rather than seconds, but needs sightlines, power, communications and something or someone to watch the feed. Aircraft give excellent detection on demand at high cost per hour and only while flying. Satellites cover everything without asking, but a polar-orbiting sensor passes only a few times a day and a geostationary one trades resolution for constant watch, so both have a smallest fire they can see at all, set by pixel size and by how hot and large a spot must be to raise the pixel's signal. The rule for choosing: fix the smallest fire you must not miss and the minutes you can afford to lose, then see which platforms survive both constraints, and only then compare their cost per unit of area covered. After this Concept you can compare detection platforms on latency, coverage and cost for a specific area at risk.
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Compare detection platforms on three numbers and the pattern is always the same. In-situ sensors — a gas or heat node on a pole, a detector on a ceiling — can call a fire within seconds, but only where one was installed, so coverage costs money linearly. A camera tower watches tens of kilometres in every direction for minutes-to-detect rather than seconds, but needs sightlines, power, communications and something or someone to watch the feed. Aircraft give excellent detection on demand at high cost per hour and only while flying. Satellites cover everything without asking, but a polar-orbiting sensor passes only a few times a day and a geostationary one trades resolution for constant watch, so both have a smallest fire they can see at all, set by pixel size and by how hot and large a spot must be to raise the pixel's signal. The rule for choosing: fix the smallest fire you must not miss and the minutes you can afford to lose, then see which platforms survive both constraints, and only then compare their cost per unit of area covered. After this Concept you can compare detection platforms on latency, coverage and cost for a specific area at risk.
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