Safety & Relief Fundamentals

29 engineering guides for pressure relief, emergency systems, and process safety

Pressure Relief

Emergency & Flare Systems

Blowdown Fundamentals

API 521

Blowdown systems: API 521 depressuring, orifice sizing, low-temperature design, and emergency isolation.

API 521 Depressuring

Blowdown Time Fundamentals

API 521

Blowdown time calculations: depressuring rates, API 521 methods, choked flow analysis, and two-phase blowdown for emergency depressurization design.

API 521 Time Calc

Depressurizing System Fundamentals

API 521

Depressurizing systems: emergency depressurization design per API 521, blowdown valve sizing, fire case analysis, and flare system integration.

API 521 BDV Sizing

Gas Rate Time Fundamentals

Inventory & Blowdown

Gas rate time calculations: gas inventory, fill time, blowdown timing, and line pack operations.

Inventory Rate-Time

ESD System Fundamentals

DOT 49 CFR 192

Emergency Shutdown (ESD) system design fundamentals: valve placement, logic design, fail-safe requirements per DOT 49 CFR 192, and compressor station safety.

49 CFR 192 ESD Logic

ESD Valve Fundamentals

IEC 61511

Emergency shutdown valve fundamentals: ESD valve design per IEC 61511, actuator selection, partial stroke testing, SIL-rated valve assemblies, and fail-safe design.

IEC 61511 Actuators

Flare Disposal System Fundamentals

API RP 521

Flare disposal system design: header sizing, knockout drum design, API RP 521 methodology, Mach number limits, and Souders-Brown velocity calculations.

API 521 Flare System

Flare Radiation Fundamentals

API RP 521

Flare radiation analysis: API RP 521 limits, point source model, and safe separation distances.

API 521 Thermal Radiation

Flare Backpressure Fundamentals

API 521

Flare backpressure calculations: API 521 limits, relief valve capacity effects, header pressure drop, and network hydraulic analysis.

API 521 Backpressure

Fire & Consequence Modeling

Consequence Modeling Fundamentals

API 521 / CCPS / TNO

Consequence modeling fundamentals: gas dispersion, thermal radiation, overpressure, and HCA determination per API 521, CCPS, TNO Yellow Book, and 49 CFR 192.

CCPS Dispersion

Gas Leak Rate Fundamentals

API 581

Gas leak rate calculations: orifice equations, choked vs unchoked flow, API 581 hole size categories, dispersion modeling, and emergency response planning.

API 581 Leak Rate

Jet Fire Radiation Fundamentals

API 521 / API RP 521

Jet fire radiation fundamentals: flame length correlations, thermal radiation models, wind tilt effects, and safe separation distances per API 521 and Shell FRED methodology.

API 521 Jet Fire

Pool Fire Modeling Fundamentals

SFPE Handbook

Pool fire modeling fundamentals: burning rate regression, Thomas flame height, Mudan & Croce thermal radiation, view factor geometry, and safe separation distances.

SFPE Pool Fire

BLEVE Fireball Fundamentals

CCPS / TNO Yellow Book

BLEVE fireball fundamentals: boiling liquid expanding vapor explosions, fireball correlations per CCPS and TNO, thermal radiation modeling, and safe separation distances.

CCPS BLEVE

Combustion & Flammability Fundamentals

NFPA 68/69 / API 521

Combustion and flammability fundamentals: LEL/UEL limits, Le Chatelier's mixing rule, stoichiometric combustion, flame propagation, and auto-ignition per NFPA 68/69.

NFPA 68 Flammability

Fire Water Demand Fundamentals

NFPA 15

Fire water demand fundamentals: NFPA 15 water spray design, deluge system sizing, wetted area calculations, fire pump selection, and water storage for gas plants.

NFPA 15 Deluge Systems

Atmospheric Dispersion Fundamentals

EPA SCREEN3

Atmospheric dispersion modeling: Gaussian plume model, Pasquill-Gifford stability classes, Briggs plume rise, GEP stack height, and EPA SCREEN3 methodology.

EPA Gaussian Plume

Process Safety & Emissions

Safety Engineering Quick Reference

PRESSURE RELIEF Relief Valve & Flare Design

All pressure relief per API 520/521 and ASME Section VIII

CONSEQUENCE Fire & Dispersion Analysis

Methods per CCPS, TNO Yellow Book, and SFPE Handbook

PROCESS SAFETY Risk Assessment & SIL

  • HAZOP — Guide word analysis per IEC 61882
  • LOPA — Protection layers & SIL determination
  • SIL Verification — PFDavg per IEC 61508/61511

Functional safety per IEC 61508 and IEC 61511