Blast PSI Calculator
Blast PSI is a free field calculator for blast overpressure and safe standoff. It's built for breachers, EOD and range staff, and tactical teams who need a quick, conservative estimate before a planned detonation.
Enter the explosive and its net weight. Blast PSI shows:
Overpressure and impulse
Peak overpressure (psi) and impulse at any distance.
Standoff distances
Standoff distances for DoD's 4 psi personnel line and for eardrum, lung and fatality thresholds.
Ring diagram
A ring diagram of every threshold around the charge.
Near walls / indoors
A "near walls / indoors" mode that uses reflected pressure.
Units
Imperial (lb/ft) and metric (kg/m) units.
Exposure log
Record estimated exposures per operator and see at a glance who has been at or above 4 psi. Entries stay on your device.
Built on public references: Kingery-Bulmash airblast curves (the basis of UFC 3-340-02 and CONWEP), TNT-equivalence factors from UFC 3-340-02 and the NCTC, and injury thresholds from Glasstone & Dolan and TM 5-1300. Every number cites its source in the app.
Works with no signal.
No account, no ads, no tracking, no data collected.
Free
Need help with the app? Email contact@oakenshadellc.com. See Support for what to include.
Blast PSI is a planning aid. It does not replace your agency's minimum safe distance procedures, a qualified breacher or EOD technician, or measured overpressure. It does not model fragments, debris, or shaped and cutting charges. App screens shown are from the app itself; interface details may evolve between releases.