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This project is funded by the European Union Projekat finansira Evropska Unija. TOP EVENTS CONSEQUENCE ANALYSIS MODELS Antony Thanos Ph.D. Chem. Eng. [email protected] Consequence analysis framework. Release scenarios. Accident type. Hazard Identification. Event trees.

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Top events consequence analysis models antony thanos ph d chem eng antony thanos@gmail com

This project is funded by the European Union

Projekat finansira Evropska Unija

TOP EVENTSCONSEQUENCE ANALYSIS MODELS Antony ThanosPh.D. Chem. [email protected]


Release

scenarios

Accident

type

Hazard Identification

Event

trees

Dispersion models

Release models

Consequence

results

Release

quantification

Fire, Explosion Models

Domino effects

Limits of

consequence analysis


  • Pool fire

    • Ignition of flammable liquid phase

Main consequence

Thermal radiation

Liquid fuel tank fire


  • Pool fire characteristics

    • Pool dimensions (diameter, depth)

      • Confined pool (liquid fuels tank/bund fire) :

        • Tank fire pool : diameter equal to tank diameter dimension

        • bunds : pool diameter estimated by equivalent diameter of bund


  • Pool fire characteristics (cont.)

    • Pool dimensions (diameter, depth) (cont.)

      • Unconfined pool (LPG pool from LPG tank failure –no dike present):

        • Theoretically maximum pool diameter is set by balance of release feeding the pool and combustion rate from pool

Release

to pool

Combustion

rate


  • Pool fire characteristics (cont.)

    • Pool dimensions (diameter, depth) (cont.)

      • Unconfined pool :

        Min : release rate (kg/sec)

        Mcomb : combustion rate (kg/sec)

        mcomb : specific combustion rate (kg/m2.sec)

        • In real life, pool is restricted by ground characteristics. Typical values for assumed depth: 0.5-2 cm (depending on ground type, higher values reported for sandy soils)



  • Pool fire models

    • Combustion rate per pool surface on empirical equations (Burges, Mudan etc.)

      • Example :


  • Pool fire models (cont.)

    • Combustion rate for liquids not exceeding 0.1 kg/m2.sec. Upper range for low boiling point hydrocarbons

    • Flame dimension from empirical equations (Thomas, Pritchard etc.)

      • Example, Thomas correlation :

      • Big pools : Hf/Dp in the range of 1-2


  • Pool fire models (cont.)

    • Point source model (cont.)

      • No flame shape taken into account

      • A fraction of combustion energy is considered to be transmitted by ideal point in pool center

Thermal radiation

transmitted

semi spherically


  • Pool fire models (cont.)

    • Point source model (cont.)

      • Increased inaccuracies near pool end (important for Domino effects)


Pool diameter

Flame height

Pool depth

  • Pool fire models (cont.)

    • Solid flame radiation model, radiation emitted via flame surface


  • Pool fire models (cont.)

    • Solid flame radiation model (cont.)

      • Calculation based on :

        • flame shape (usually considered cylinder -tilted or not-),

        • distance from flame (View Factor),

        • emissive power (thermal radiation flux at flame surface)



  • Pool fire models (cont.)

    • Solid flame radiation model (cont.)

      • View Factor : function of distance of receptor from flame and flame dimensions. Different equation for different flame shapes

      • Transmissivity coefficient : Absorbance of thermal radiation by atmosphere components - e.g. humidity, CO2 –

        • Correlation with relative humidity (R.H.) level and distance to “receptor”)

        • High R.H, low transmissivity coefficient

        • More important for far-field effects (due to increased distance)


  • Pool fire models (cont.)

    • Solid flame radiation model (cont.)

      • Emissive power :

        • Depending on pool size, substance

        • For big pools, soot formation (20 kW/m2), masking of flame, significant reduction of average flame emissive power



  • Pool fire models (cont.)

    • Solid flame radiation model (cont.)

      • Emissive power : (cont.)

        • Experimental Gasoline pool examples :

          Dp=1 m, E=120 kW/m2

          Dp=50 m, E= 20 kW/m2

        • Medium to low emissive power for big pools (thermal radiation flux, up to 60 kW/m2 for liquid fuels)

        • LPGs, LNG, provide higher emissive power (up to 150-270 kW/m2 for LPG, 250 kW/m2 for LNG)


  • Pool fire models (cont.)

    • Solid flame radiation model (cont.)

      • Emissive power : (cont.)

        • One example of correlations available for max emissive power :


  • Pool fire models (cont.)

    • Solid flame radiation model (cont.)

      • Emissive power : (cont.)

        • Final emissive power must take into account smoke production. Example correlations :

          s, smoke coverage of surface

          Dp, pool diameter (m)

          Esmoke, emissive power of smoke (kW/m2)


  • Pool fire models (cont.)

    • Solid flame radiation model (cont.)

      • Emissive power : (cont.)

        • Please be careful !!!!

          • Make sure radiation fraction used is in-line with experimental data if available

          • Evaluate calculation results for emissive power with experimental results, if available


  • Pool fire models (cont.)

    • UK HSE suggestions for LPGs :

      • Emissive power : 200 kW/m2 over half flame height

    • Some conservative assumptions

      • For unconfined LPG cases, for theoretical pool calculation :

        • butane fire instead of similar propane release (lower boiling rate, higher pool diameter

        • low ambient temperature examined (as above)

      • Low relative humidity examined (high transmissivity coefficient)


  • Pool fire models (cont.)

    • Example results for propane pool fire Dp=10 m, wind speed 5 m/sec T=25 °C (confined fire, Aloha),

      • flame height Hf : 21 m

      • combustion rate M : 400 kg/min


  • Pool fire models (cont.)

    • Example results for Methanol tank, Dtank=20 m, H tank=20 m, T= 25 C°, atmospheric conditions D5, 2 in hole on tank shell at ground level (burning unconfined pool, Aloha)

      • pool diameter Dp = 27 m

      • flame length : 11 m


  • Fireball, BLEVE (Boiling Liquid Expanding Vapour Explosion)

    • Rapid release and ignition of a flammable under pressure at temperature higher than its normal boiling point

Main consequence

Thermal radiation

Secondary consequences:

  • Fragments (missiles)

  • Overpressure

LPG BLEVE (Crescent City)


  • Fireball/BLEVE characteristics

    • Very rapid phenomenon (expanding velocity 10 m/sec)

    • Limited duration (up to appr. 30 sec, even for very large tanks)

    • Significant extent of fireball radius (in the order of 300 m for very big tanks, ≈ 4000 m3)

    • Very high emissive power (in the order or 200-350 kW/m2)

    • No precise capability for prediction of when it will happen (usual initial step for tanks exposed to heat -pool fire, jet flame-, opening of PSVs)


  • Fireball/BLEVE characteristics and models (cont.)

    • Radius and duration from correlations with tank content, example(AIChE CCPS) :

      • t, duration (sec)

      • m, mass (tn)

      • No significant deviations for various correlations available, example results for full propane tank BLEVE (100 m3)



  • Fireball/BLEVE characteristics and models (cont.)

    • Mass in fireball calculations :

      • Typically whole tank content (worst case approach.)

      • Netherlands (BEVI method) : gas phase + 3 x flash fraction of liquid phase at failure pressure.

        • For typical failure pressure in LPGs with hot BLEVEs, results to whole tank content

        • For propane at usual atmospheric conditions, results to whole tank content


Evolution of fireball/BLEVE


  • Fireball/BLEVE characteristics and models (cont.)

    • Solid flame radiation model (cont.)

      • Calculation based on :

        • sphere shape at contact with ground,

        • distance from fireball (sphere View Factor),

        • fireball emissive power (thermal radiation flux at fireball surface)


  • Fireball/BLEVE characteristics and models(cont.)

    • Solid flame radiation model (cont.)

      • View Factor : function of distance of receptor from flame and fireball radius

      • Transmissivity coefficient : as in pool fire case


  • Fireball/BLEVE characteristics and models (cont.)

    • Emissive power in fireball calculations :

      • Correlations are available for emissive power calculation based on :

        • vapour pressure at failure conditions (AIChE CCPS)

          Pv, vapour pressure at failure (MPa)

        • and/or mass involved, duration, size of fireball

      • Experimental data provide values up to 350 kW/m2

      • UK, HSE suggestion >270 kW/m2


  • Fireball/BLEVE models (cont.)

    • Example results (full 100 m3 propane tank BLEVE, Aloha)

      • But, duration is only 13 sec. For limit values set in TDU (not in kW/m2), the relevant thermal radiation flux limit must be calculated


  • Fireball/BLEVE models (cont.)

    • Example results (full 100 m3 propane tank BLEVE, Aloha) (cont.)

      • For t=13 sec,

        • 1500 TDU corr. to 35 kW/m2

        • 450 TDU corr. to 14 kW/m2

        • 170 TDU corr. to 6.9 kW/m2


  • Jet flame

    • Ignition of gas or two-phase release from pressure vessel

Main consequence

Thermal radiation

Propane jet flame test


  • Jet flame characteristics

    • Results as outcome of gas or two phase releases of flammable substances

    • Cone shape

    • Long duration (minutes to hours, depends on source isolation)

    • Very high emissive power (in the order or 200 kW/m2)

    • Soot expected, but not affecting radiation levels


  • Jet flame models

    • Combustion rate determined by release rate

    • Dimensions from empirical equations. Example of simplified Mudan-Cross equation

      L= jet flame length

      d= release point diameter

      Ct= fuel content permole in stoichiometric mix

      of fuel/air

      ΜWa= air molecular weight

      MWf= fuel molecular weight


  • Jet flame models (cont.)

    • Dimensions from empirical equations. Example of simplified Considine-Grint equation for LPGs

      L= jet flame length

      M= release rate (kg/sec)

      W= jet radius at flame tip (m)


  • Jet flame models (cont.)

    • Point source models

      • Single point : all energy is released from flame “center”. Similar to relevant point source model for pool fires

      • Multipoint source : several point along jet trajectory taken into account


  • Jet flame models (cont.)

    • Solid flame radiation model

      • Radiation emitted via flame surface

      • Calculation based on :

        • shape (cylinder, tilted or not)

        • distance (View Factor)

        • emissive power



  • Jet flame models (cont.)

    • Solid flame radiation model (cont.)

      • View Factor : function of distance of receptor from flame and flame dimensions for shape assumed

      • Transmissivity coefficient : as in pool fires, fireball/BLEVE

      • Emissive power : Estimated by flame dimension (surface) and energy released

        E= Emissive power (kW/m2)

        M= release rate (kg/s)

        ΔΗc= combustion energy (kJ/s)

        A= jet surface area, m2

        Fs= fraction of combustion energy radiated

        uj= expanding jet velocity (m/sec)


  • Jet flame models conservative approaches

    • Examination of horizontal jet

      • Produce more extended thermal radiation zones

      • Have direct effect via impingement in near by equipment

    • Wind speed (for models taking into account flame distortion due to wind) :

      • Vertical jets : High wind speed (UK HSE suggestion 15 m/sec)

      • Horizontal jets : Low wind speed (UK HSE suggestion 2 m/sec)





  • Vapour cloud dispersion (cont.)

    • Endpoints :

      • Toxics : several toxicity endpoints (e.g. IDLH, LC50)

      • Flammables : LFL, ½ LFL

        • Deaths expected within cloud limits where ignition is possible (Flash fire) due to thermal radiation and clothes ignition

        • Reporting of LFL, ½ LFL is for theoretical extend of cloud, as no ignition is assumed on cloud path

        • Very extended clouds expected for LPGs, especially in catastrophic failure cases (in the order of 500-1500 m)


  • Vapour cloud dispersion (cont.)

    • Endpoints : (cont.)

      • Flammables : (cont.)

        • Usually ignition sources outside establishment premises limit actual cloud

        • Protection zones not justified to take into account flammable dispersion till LFL, ½ LFL




  • Vapour cloud (gas) dispersion (cont.)

    • Release conditions affecting dispersion :

      • substance properties (Boiling Point etc.)

      • pressure, temperature at containment

      • release rate and area

      • release point height

      • release direction (upwards –PSV-, horizontal)


  • Vapour cloud (gas) dispersion (cont.)

    • Meteorological conditions affecting dispersion :

      • atmospheric stability class (A-F),

      • wind speed,

      • air temperature,

      • humidity (for some substances reacting with water as for example HF or other polar substances : SO2, NH3 etc.)

      • Type of area : rural/industrial/urban, roughness factor




  • Vapour cloud (gas) dispersion (cont.)

    • Atmospheric stability : (cont.)

      • Usually attributed to standardized class A-F (Pasquill)

        • A : unstable, in combination with high winds favors dispersion

        • D : neutral

        • F : stable, minimum mixing in atmosphere

      • Other parameter to attribute atmospheric stability, Monin-Obukhov length (positive for stable conditions, negative for unstable conditions)




  • Vapour cloud (gas) dispersion (cont.)

    • Wind speed :

      • Wind speed referred in meteorological data usually refer to measurement at 9-10 m height

      • Boundary layer effect (variation of speed with height)




  • Vapour cloud (gas) dispersion (cont.)

    • Meteorological conditions :

      • Typical set under interest in Safety Reports :

        • D5 : stability class D, uref=5 m/sec (unstable conditions)

        • F2 : stability class D, uref=2 m/sec (stable conditions). Worst case for extent of vapour cloud, especially in heavy gas dispersion


  • Vapour cloud (gas) dispersion (cont.)

    • Type of surroundings : rural/industrial/urban

      • Refers to variation of height in elements of surrounding

      • Usually attributed via “roughness factor”


  • Vapour cloud (gas) dispersion (cont.)

    • Type of surroundings (cont.)

      • Conservative approach : open country (rural)

    • Averaging time :

      • Variation in time, due to turbulence, of wind characteristics :

        • speed

        • direction


y

not exposed

x

T=0

average wind

direction

y

exposed

x

T=t

  • Vapour cloud (gas) dispersion (cont.)

    • Averaging time : (cont.)

      • For continuous releases, concentration at constant location (x, y, z) is not constant



  • Vapour cloud (gas) dispersion (cont.)

    • Averaging time : (cont.)

      • Very important to use averaging time in models, suitable to exposure time under interest

      • Models may use parameters for certain averaging time, which might not be suitable for application in Safety Report. PLEASE ALWAYS CHECK !!!

      • Gaussian models use implicit 10-min averaging time but…


  • Vapour cloud (gas) dispersion (cont.)

    • Averaging time : (cont.)

      • Toxics exposure usually under interest for period of 30 min (due to LC50 30 min endpoints etc.)

      • Aloha-DEGADIS (Heavy Gas Dispersion) uses 5 min for toxics

      • Ignition of flammable cloud is related with very low exposure time (time just for ignition to happen).

      • Aloha-DEGADIS uses 10 sec for flammables (e.g. LPGs, no matter if toxic effect is examined)


Averaging time = 1 sec

Averaging time = 30 min


  • Vapour cloud (gas) dispersion (cont.)

    • Averaging time : (cont.)

      • Reason for reporting both LFL, ½ LFL in flammable dispersion

        • ½ LFL reporting contributes to uncertainty of averaging time (conservative approach)



  • Vapour cloud (gas) dispersion (cont.)

    • Passive (neutral) dispersion (Gauss) :

      • Basic characteristics:

        • Maximum concentration at centreline

        • Concentration reducing with increasing distance from source

        • If release at ground level, maximum concentration at ground level


u, wind speed at z (m/sec)

M, release rate flow (kg/sec)

Hd, active release height (m)


  • Vapour cloud (gas) dispersion (cont.)

    • Passive (neutral) dispersion (Gauss) : (cont.)

      • σy, σz :

        • functions of stability class with x and roughness factor

        • usually given for 10-min averaging time

        • proper correction of σy based on necessary averaging time is required



  • Vapour cloud (gas) dispersion (cont.)

    • Passive (neutral) dispersion (Gauss) : (cont.)

      • Equations provided for point stationary source (no momentum)

      • But jets of releases have significant momentum due to high velocity… modifications needed in model to take into account release momentum


  • Vapour cloud (gas) dispersion (cont.)

    • Passive (neutral) dispersion (Gauss) : (cont.)

      • For jets of releases modifications are needed, typical example : plume rise parameter to modify the release source point at downstream location

Modified

Original


  • Vapour cloud (gas) dispersion (cont.)

    • Flue gases dispersion

      • Example : pool fire combustion products, e.g., SO2

      • Special characteristics :

        • Large area of source (e.g. tank area, bund area), (not point source). Modifications are available to models or sources are treated as point ones

        • High temperature of flue gases

        • Relevant plume rise equations provided for stacks (Briggs, Holland equations), provide unrealistic plume rise height

      • Conservative approach, no plume rise, dispersion begins from flame end



  • Vapour cloud (gas) dispersion (cont.)

    • Plume rise effects

      • Concentration at centrelines not continuously decreasing with distance

      • Max concentration at centreline appears at distance from source


  • Vapour cloud (gas) dispersion (cont.)

    • Plume rise effects (cont.)

      • Example results from calculation of SO2 dispersion from dike fire of heating oil tank (D5, release rate 0.25 kg/sec SO2, dike equivalent diameter 66 m)



  • Vapour cloud (gas) dispersion (cont.)

    • Heavy gas dispersion (cont.)

      • Maximum concentration expected at centerline

      • Concentration decreases with increasing distance

      • More extended plume compared to neutral dispersion


  • Vapour cloud (gas) dispersion (cont.)

    • Heavy gas dispersion (cont.)

      • Meteorological data

        • F2 produce more extended cloud

      • Propane/butane cases

        • same release source (e.g. same hole size) will produce more extended cloud for propane due to higher release rate





  • Vapour Cloud Explosion (VCE)

    • Delayed ignition of flammable vapour cloud under partial confinement (obstacles within cloud) producing overpressure during flame front propagation

Main consequence

Overpressure

Secondary consequences:

  • Fragments (e.g. broken glasses)

VCE results (Flixborough)


  • Vapour Cloud Explosion (VCE) characteristics

    • Very short duration (<1 sec)

    • Models, high uncertainty due to several assumptions used in every model

    • Type of models:

      • CFD (FLACS, PHOENIX etc.)

      • TNT blast charge (TNT equivalency)

      • Air-fuel charge blast (Multi-Energy, Baker -Strehlow -Tang etc.)


  • Vapour Cloud Explosion (VCE) models

    • TNT equivalency model

      • Simple, based on analogy with explosives effects

      • A fraction of combustion energy released in cloud is attributed to produce overpressure

      • The former energy fraction is recalculated as equivalent (on energy basis) mass of TNT

      • The effects are defined based on known correlation of overpressure with TNT mass


  • Vapour Cloud Explosion (VCE) models (cont.)

    • TNT equivalency model (cont.)

      • αe, refers to part of combustion energy released producing overpressure (1-10%)

      • High uncertainty in both αe value and quantity of flammables (released mass –till what time ???-, mass within LFL-UFL) to be used

      • Review on topic by TNO Yellow Book and AICheJ CCPS Guideline


  • Vapour Cloud Explosion (VCE) models (cont.)

    • TNT equivalency model (cont.)

      • Some comments/examples on selection of mass and αe :

        • αe must be selected along with suitable flammable mass

        • for αe1-5%, mass must not contain only the part of cloud in LFL-UFL section

        • flammable mass must take into account not only gas but also liquid droplets (aerosol) in 2-phase releases

        • Dow approach : mass defined by release rate and time to maximise LFL distance


  • Vapour Cloud Explosion (VCE) models (cont.)

    • TNT equivalency model (cont.)

      • Some comments/examples on selection of mass and αe : (cont.)

        • mass defined by time to reach ignition source or time to stop release (time for energizing isolation valves)

        • HSE suggests TNT mass double the gas mass in confined areas

      • Explosives blast and VCE present differences, as explosives have short duration higher shock wave peak values.

      • TNT equivalency model is approximation of phenomenon based on statistical analogies


  • Vapour Cloud Explosion (VCE) models (cont.)

    • TNT equivalency model (cont.)

      • Overpressure calculated by diagram

        for distances required

      • Uncertainty on centre of explosion

        to be considered

      • Similar diagrams for positive phase

        duration, impulse


  • Vapour Cloud Explosion (VCE) (cont.)

    • TNO Multi-Energymodel :

      • Only confined areas of cloud are considered

      • Partial explosions from confined areas expected

      • Energy released assuming stoichiometric combustion, based on air contained in areas taken into account (average 3.5 MJ/m3 of air for most hydrocarbons) uniform concentration of flammable in confined areas assumed



  • Vapour Cloud Explosion (VCE) (cont.)

    • TNO Multi-EnergyModel : (cont.)

      • Similar graphs for positive phase duration, dynamic pressure

      • Blast strength 10 : detonation, explosives case, not valid for VCEs as propagation of blast via detonation requires high homogeneity in cloud


  • Vapour Cloud Explosion (VCE) (cont.)

    • TNO Multi-EnergyModel : (cont.)

      • Disadvantage : complex empirical rules for (TNO Yellow Book, Assael) :

        • definition of confined areas

        • definition of successive or simultaneous blast in confided areas

        • selection ofblast strength (confinement increase, increases blast strength

      • HSE suggests blast strengths 2 and 7


  • Vapour Cloud Explosion (VCE) (cont.)

    • Baker-Strehlow-Tang model

      • Similar principles as TNO Multi-Energy model

        • confined areas only taken into account

        • stoichiometry of air with fuel in confined areas

      • Gas type “reactivity” (susceptibility to flame front acceleration) taken also into account along with obstacle density

        • methane, CO : low reactivity

        • H2, acetylene, ethylene/propylene oxide : high reactivity

        • other substances : medium



  • Vapour Cloud Explosion (VCE) (cont.)

    • Baker-Strehlow-Tang model (cont.)

      • Overpressure from graph using Sachs distance and flame speed

        • Energy to be used double to actual as graph presents free air blast (not surface blast)


Ignition time 2 min

Composite for unknown ignition time


  • Pesticides fires and dispersion

    • Variation of stored substances quantities within year due to seasonal production of some products.

      • Evaluation of stored quantities distribution could be required to evaluate quantities to be taken into account in calculations.

    • Some times, active substance stored in powder form

    • Specific combustion rate rather low (TNO Green Book) : in the range of 0.02 kg/m2.sec


  • Pesticides fires and dispersion(cont.)

    • Special characteristic of pesticides : when burnt, not all substance is consumed, flue gases contain unburned pesticide substances (“survivor” fraction)

    • In case of fire, dispersion of flue gases must examine :

      • Combustion products (e.g. SO2, HCl, NO2 etc.)

      • Unburned pesticide active substance


  • Pesticides fires and dispersion(cont.)

    • UK HSE suggests stoichiometric conversion of S, Cl to SO2 and HCl.

    • Conversion ratios :

      • C to CO : 5%

      • N to HCN and NO2 : 5%

    • According to TNO Green Book, formation rate of NO2, HCN and NO decreases with this order, Taking into account the similar toxicity of the former, conversion of N to NO2 only is conservative


  • Pesticides fires and dispersion (cont.)

    • Survivor fraction in flue gases : 0.5-10% of combustion rate of substance at source

    • Lower survivor fractionfor high boiling point substances

    • UK HSE suggests survivor fraction 10% otherwise justification must be provided


  • Pesticides fires and dispersion (cont.)

    • Especially in closed warehouse cases :

      • what is plume rise for flue gases ??

      • which is the combustion rate ??

    • Plume rise in warehouse flue gases

      • For fire in full development plume rise might be high, but potentially low in initial phase of fire

      • Typical equations fail, as producing unrealistic plume rise


  • Pesticides fires and dispersion (cont.)

    • Combustion rate, affected by type of fire

      • Roof collapse

        • As in open area, fuel controlling

        • High flue gas temperature

      • Ventilation controlled

        • roof intact, some window breakage (limited release area)

        • fire rate controlled by availability of oxygen in warehouse

        • low temperature of flue gases, low plume rise


  • Pesticides fires and dispersion (cont.)

    • UK HSE suggests :

      • plume rise set at max 50 m

      • calculations for source via a few m2 area of window (nevertheless, recognized as pessimistic), (NTUA methodology refers to 3 m2)

      • special models

    • UK HSE suggests meteorological condition to be examined as worst case ones :

      • F2

      • D5, D15 with low inversion height (400 m)


  • Pesticides fires and dispersion (cont.)

    • NTUA methodology suggests the following cases :

      • Roof collapse : flue gas rate 8 kg/m2.sec (per warehouse area), T=500 °C

      • Ventilation controlled (roof intact) : flue gas rate 5 kg/m2.sec (per opening area, assumed 3 m2), T=140 °C




  • Accidents with effects to environment

    • No mature and wide-used quantitative models for estimation of effects to environment

    • Qualitative models (applied some times, examples :

      • Energy Institute (ex. IP) Screening Tool

      • Belgium (Flanders) Richtlijn Milieurisicoanalyse

      • IPC Guidance Note on Storage and Transfer of Materials for Scheduled Activities, Irish EPA

    • No unique approach in EU members (in many countries no specific approach) in relevant requirements


  • Literature for Top Events Consequence Analysis Models

    • Lees’ Loss Prevention in the Process Industries, Elsevier Butterworth Heinemann, 3nd Edition, 2005

    • Methods for the Calculation of Physical Effects due to Releases of Hazardous Materials (Liquids and Gases), Yellow Book, CPR 14E, VROM, 2005

    • Methods for the Determination of Possible Damage to People and Objects Resulting from Releases of Hazardous Materials , Green Book, CPR 16E, TNO, 1992

    • Guidelines for Chemical Process Quantitative Risk Analysis, CCPS-AICHE, 2000

    • Guidelines for Consequence Analysis of Chemical Releases, CCPS-AICHE, 1999

    • Guidelines for Evaluating the Characteristics of Vapour Cloud Explosions, Flash Fires and BLEVEs, CCPS-AICHE, 1994


  • Literature for Top Events Consequence Analysis Models (cont.)

    • Safety Report Assessment Guides (SRAGs), Health and Safety Executive, UK

    • Risk Assessment Methods for Warehouses - Computer Program FIREPEST II, Health and Safety Executive, 1997

    • Assael M., Kakosimos K., Fires, Explosions, and Toxic Gas Dispersions, CRC Press, 2010 Benchmark Exercise in Major Accident Hazard Analysis, JRC Ispra, 1991

    • Rew P., Humbert W., Development of Pool Fire Thermal Radiation Model, HSE Contract Research Report 96, 1996

    • McGrattan K., Baum H., Hamins A. Thermal Radiation from Large Pool Fires, National Institute of Standards and Technology, NISTIR 6546, Nov 2000

    • Taylor J., Risk Analysis for Process Plant, Pipelines and Transport, E&FN SPON, 1994


  • Literature for Top Events Consequence Analysis Models (cont.)

    • Drysdale D., Fire Dynamics, J. Wiley and Sons, 2nd Edition, 1999

    • Beychok M., Fundamentals of Stack Gas Dispersion, 3rd Edition, 1994

    • C. Delvosalle, F. Benjelloun, C. Fiévez,, A Methodology for Studying Domino Effects, Faculté Polytechnique de Mons,Ministere Federal de l’;Emploi et du Travail, July 1998

    • RIVM, Reference Manual Bevi Risk Assessments, 2009

    • ALOHA, Users Manual, US EPA, 2007

    • ALOHA Two Day Training Course Instructor's Manual

    • Environmental risk assessment of bulk storage facilities: A screening tool, EI, 2009

    • Richtlijn Milieurisicoanalyse, 2006


  • Literature for Top Events Consequence Analysis Models (cont.)

    • IPC Guidance Note on Storage and Transfer of Materials for Scheduled Activities, Irish EPA, 2004

    • N. Markatos, NTUA, Chemical Engineering Department, Methodology of Assessment of Consequence from fire in Pesticide installations, 2001 (in Greek)


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