Blast Effects API

Blast-effects and TNT-equivalence maths as an API for safety engineering and education, computed locally and deterministically. The energy endpoint converts between a TNT charge mass and the energy it releases using the conventional 4.184 MJ per kilogram, in both directions, including the kiloton equivalent. The scaled-distance endpoint computes the Hopkinson-Cranz scaled distance Z = R / W^(1/3) from a standoff distance and a charge weight — the cube-root scaling law means two blasts with the same Z produce the same overpressure — and inverts it to give the standoff distance for a target Z, which is how safety distances are set for a given charge. The overpressure endpoint estimates the peak side-on overpressure with the Brode (1955) correlation from the scaled distance (or from distance and charge), in kilopascals, bar and psi, with a qualitative damage assessment from shattered glass to structural collapse. Charge is in kilograms of TNT, distance in metres and energy in joules. Everything is computed locally and deterministically, so it is instant and private. Ideal for blast-resistant design, demolition, mining, process-safety and emergency-planning app developers, standoff-distance and overpressure tools, and engineering education; for engineering use, consult the applicable standards. Pure local computation — no key, no third-party service, instant. Live, nothing stored. 3 endpoints. This is explosive blast effects; for earthquake magnitude and energy use an earthquake-magnitude API.