27 calculators for pressure relief, flare design, fire modeling, and safety analysis per API 520, API 521, NFPA, and IEC standards.
Size pressure safety valves for gas, liquid, steam, and two-phase service per API 520.
Calculate fire-case relief loads for vessels and equipment using API 521 wetted area and heat input methods.
Size emergency relief devices for runaway exothermic reactions using DIERS methodology and vent sizing.
Verify inlet piping pressure drop to PSV stays within the API 520 3% accumulated backpressure limit.
Size relief valve outlet headers and check built-up backpressure for multiple PSV discharge piping systems.
Size tank breathing vents for normal thermal breathing, liquid movement, and emergency fire-case venting per API 2000.
Saturated-liquid omega ω, Leung explicit critical-pressure ratio η_c, critical mass flux G_crit, and API 526 orifice selection (D–T) for two-phase PSV sizing.
Gas (critical), liquid (Q-form), and steam (Napier) rupture disc area sizing with K_d/K_c factors, burst tolerance ±5%, and NPS selection (1–10 in).
Calculate thermal radiation from elevated and ground flares using API 521 point source and multi-point methods.
Calculate pressure drop through flare headers, sub-headers, and collection systems for relief scenario analysis.
Size flare knockout drums, liquid seal drums, and disposal system components per API 521 guidelines.
Model atmospheric dispersion of combustion products and emissions from flare stacks and process vents.
Anti-pulsation flare-header seal drum: required area, drum diameter, gas velocity, seal-break pressure, and water inventory at 70 ft/s anti-pulsation criterion.
Iterative stack-height sizing for radiation heat-flux to Worker/Fence/Equipment receivers per API 521 Table 9 (500/1500/2000 Btu/hr·ft²), with wind-tilt and CO dispersion check.
Calculate vessel depressurization time, minimum metal temperature, and blowdown valve sizing per API 521.
Design emergency depressurization systems with blowdown valve sizing, orifice selection, and ESD logic timing.
Size emergency shutdown valves for pipeline and process isolation with closure time and actuator requirements.
Calculate thrust loads from blow-off valve venting, concrete support block sizing, and anchor bolt design using momentum balance.
Model gas release rate over time during inventory blowdown for flare load analysis and dispersion modeling.
Model gas release consequences including dispersion distances, hazard zones, and toxic/flammable cloud extents.
Calculate thermal radiation from pressurized gas jet fires including flame length, tilt angle, and exclusion zones.
Model liquid pool fire radiation with burning rate, flame height, view factor, and thermal exclusion zones.
Calculate BLEVE fireball diameter, duration, and thermal radiation for pressurized liquid vessel failure scenarios.
Calculate gas release rates through pipe holes and cracks for consequence analysis and emergency planning.
Calculate lower and upper explosive limits for gas mixtures, flash points, and auto-ignition temperatures.
Calculate fire water demand for deluge systems, monitors, and hydrants per NFPA 15 and facility risk assessment.
Gaussian dispersion with Briggs σ_y/σ_z (rural+urban × A-F stability), ground-level concentration, and bisection-solved distance to ERPG-2 (30 ppm) / ERPG-3 (100 ppm).
Structured HAZOP worksheet tool with guide words, deviations, causes, consequences, and safeguard documentation.
Calculate mitigated event frequency using independent protection layers, initiating event frequency, and PFD values.
Verify safety instrumented function PFD against SIL target using sensor, logic solver, and final element failure rates.
Estimate fugitive emissions from valves, flanges, pumps, and connectors using EPA emission factors and LDAR data.
Calculate methane emissions from pneumatic controllers and pumps per EPA NSPS OOOOa reporting requirements.
Estimate greenhouse gas emissions from combustion, venting, and flaring for EPA Subpart W reporting.
Standing + working loss for fixed/IFR/EFR tanks with K_E expansion, K_S saturation, K_N turnover factor, crude/gasoline TVP, plus NSPS Kb / OOOOa / Title V threshold chips.
Rim seal (mech-shoe / liquid-mounted / vapor-mounted, primary + secondary), withdrawal, deck-fitting (gauge, drain, sample, vac breaker), and bolted deck-seam losses.
SPCC 110% / NFPA 100% containment-volume check with rain allowance, freeboard, multi-tank base-area subtraction, and recommended dike height when deficient.
Bay count, arm count, pump HP, VOC emission factors (Crude/Gasoline/Diesel/NGL), VRU capture credit, and NSPS XX / Title V trigger chips.
Start here for any new vessel or equipment requiring overpressure protection.
Required for high-pressure systems >1000 psig or inventories with fire exposure risk.
Use for facility siting studies, QRA, and equipment spacing verification.
API 520/521 sizing methodology, orifice selection, backpressure effects, and inlet loss criteria.
API 521 depressurization philosophy, minimum metal temperature, and blowdown rate determination.
API 521 fire-case heat input, wetted area calculation, drainage considerations, and insulation credits.
API 521 thermal radiation calculation, flare stack height determination, and radiation contours.
Process hazard analysis methodology, guide words, node selection, and team facilitation best practices.
Gas dispersion theory, Gaussian plume models, dense gas effects, and source term calculations.
API 2000 thermal breathing, liquid movement venting, and emergency vent sizing for storage tanks.
LEL/UEL theory, Le Chatelier's rule for mixtures, flash point, and auto-ignition temperature.