System Configuration
Pressure Vessel
Piping System
Both in Series
Pressure Test
Purge / Inert
General
Test Medium
Pressures
Reference only — used for passive test pressure check against code bounds.
Default 1.01325 bar. Adjust for site elevation if required.
Volume
For vessels: total internal volume. For piping: use helper below (8D rule) or enter directly.
HUMAIN Engineering — Pneumatic Pressure & Leak Test Risk Assessment
ASME PCC-2-2022 · Article 501 · Mandatory Appendix 501-II & 501-III | Generated:
Configure inputs and press Calculate
STEP 1 Stored Energy
Absolute Test Pressure (Pat)
— bar abs
Atmospheric Pressure (Pa)
— bar abs
Volume (V)
— m³
κ (ratio of specific heats)
—
Stored Energy (E)
— J
Stored Energy (E)
— MJ
STEP 2 TNT Equivalent
Stored Energy (E)
— J
TNT Equivalent
— kg
STEP 3 Safe Distance Calculations
—
metres
—
Code Minimum
—
m
Blast Wave Distance
—
m
Fragment Throw Distance
—
m
Blast Consequence Thresholds — Rscaled Reference Table
| Rscaled (m/kg1/3) | Biological Effect | Structural Failure | Distance (m) |
|---|
Fragment distances are for random vessel/piping fragments per Table 501-III-2-1 (IME SLP-2-2011), unbarricaded inhabited buildings — conservative for open industrial sites. For unrestrained pipe sections or blind flange ejection, separate projectile trajectory analysis is required.
⚠ Scope & Limitations — Read Before Use
1. Conservative upper bound: Assumes instantaneous total failure releasing 100% of stored energy. Actual release depends on failure mode, material ductility, restraint, and geometry. Results are a conservative screening estimate only.2. System design not considered: Vessel geometry, nozzle orientation, pipe support/restraint, connected volume, and pressure regulation are not accounted for in the stored energy calculation.
3. Fragment table basis: Table 501-III-2-1 is based on the American Table of Distances (IME SLP-2-2011) for unbarricaded inhabited buildings. Conservative for open industrial sites.
4. Not a substitute for QRA: Where stored energy is significant, a detailed QRA and formal Hazard Analysis per PCC-2 §501-6.2(g) and Mandatory Appendix 501-IV must be performed by a competent process safety engineer.
Reference: ASME PCC-2-2022 Article 501, Mandatory Appendix 501-II & 501-III. ASME B31.3-2024 §345.5.