Development of the Consequence Model for Hazardous Substances (ESCAPE) for the Needs of Rescue Authorities

Transkriptio

1 Development of the Consequence Model for Hazardous Substances (ESCAPE) for the Needs of Rescue Authorities Jaakko Kukkonen, Kari Riikonen, Juha Nikmo, Markku Seppänen, Antti Hellsten Finnish Meteorological Institute Fire protection fund

2 Introduction Starting point: Computer program ESCAPE, Expert System for Consequence Analysis using a PErsonal computer The program addresses the accidental releases of toxic or flammable gases. The model has been applied in rescue services in Finland > 20 a. The model is a useful and user-friendly tool of assessment in the analysis of accidents.

3 Application of models and numerical results Emergency response planning Hazard and risk analysis, including analysis of past accidents Training and improving preparedness for accidents Inspection and surveillance of installations The model results are most useful in preparing in advance for accidents not commonly used operationally.

4 The financiers and users of ESCAPE Ministry of the Interior, Finland The Finnish Defence Forces Fire Protection Fund, Finland Inspecta, Finland Finnish Meteorological Institute In Finland: Rescue services (22) City of Helsinki Environment Centre Ekokem Neste Radiation and Nuclear Safety Authority University of Applied Sciences (EVTEK and HAMK) Internationally: Environment Protection Agency, Lithuania Institute of Physics of Vilnius, Lithuania State Pollution Control Authority, Norway Toray Plastics. Malaysia University of Hamburg, Germany

5 Development of the Consequence Model for Hazardous Substances (ESCAPE) for the Needs of Rescue Authorities Aims of the project in Fire protection fund General aim: More accurate and reliable evaluations of the consequences of the accidents of hazardous materials, for rescue authorities. Specific aims: 1. To update the dispersion models according to the state-of-the-art scientific knowledge, and evaluate model predictions against experimental data. 2. Improve the usability of the model in rescue services, to be more userfriendly, robust and versatile. E.g., on-line connection to weather prediction models would simplify the user s task. 3. Extend the model to work in a variety of computer environments.

6 Development of the Consequence Model for Hazardous Substances (ESCAPE) for the Needs of Rescue Authorities Work packages and schedule of the project 1. Dispersion models will be replaced by improved versions (2013) - update of the models (done) - evaluation of the models against experimental data (partly done) 2. Automatic use of weather prediction models (2014) - available weather prediction models: HARMONIE, AROME, ECMWF (the latter also global) - the user has also possibility to input measured weather data 3. Extension of the model to work in different operating environments (2015) - at present the model works only in Windows environment - environment-independent program version (Windows, Unix, Linux, Mac, mobile phones) - easy-to-use net application to operative rescue services => simplifies and diversifies the model usage

7 Management group Janne Koivukoski, chairman, SM Jaakko Kukkonen, proj.coordinator, FMI Juha Nikmo, FMI Antti Hellsten, FMI Markku Seppänen, FMI Arto Jäppinen, PvTT Markku Mäkelä, ESPL Tiina Santonen, TTL Work group Kari Riikonen, FMI Juha Nikmo, FMI Jaakko Kukkonen, FMI Mikko Aalto, FMI Kaisa Korpi, FMI Minna Rantamäki, FMI Roope Tervo, FMI Markku Seppänen, FMI Mikko Routala, LUPL SM FMI ESPL LUPL PVTT TTL Ministry of the Interior Finnish Meteorological Institute Fire and rescue services of Etelä-Savo Fire and rescue services of Länsi-Uusimaa Defence Forces Technical Research Centre Finnish Institute of Occupational Health

8 The processes included in the ESCAPE model Two-phase jet Release Source term Dispersion Effects Pool formation Catastrophic release X X X X X X length scale: release source term heavy gas passive dispersion 10 m m m < 20 km

9 A block chart of the ESCAPE model Database on the properties of substances Meteorological data and description of the release Accident databases Boiling liquid expanding vapour explosion Instantaneous release Spreading and vaporisation of a liquid pool A release through a pipe or a breach Two-phase jet Heavy cloud and passive dispersion Evaluation of doses Output data, MapInfo Heavy plume and passive dispersion

10 Dispersion model for denser than air gas clouds Meteorology and the transport of the cloud Entrainment of air: atmospheric turbulence internal turbulence of the cloud mechanical entrainment u Gravity slumping, terrain Thermodynamical and chemical processes: pollutant and entrained air phase transitions (liquid vapour) heat flux from the ground

11 A model for liquid pool spreading and evaporation Atmospheric conditions Discharge Evaporation of pool: vapour pressure and latent heat flow structure Heat transfer atmosphere - pool: convection radiation Heat transfer ground - pool: conduction convection Pool spreading: gravity resistance

12 Current status Input data for weather conditions and terrain in ESCAPE Input data for wind, temperature and humidity Input data for determining atmospheric stability Input data for determining ground roughness

13 Input data of the release conditions in ESCAPE: Release type: continuous or instantaneous Chemical substance Mass of substance stored Etc. If release conditions result in liquid pool formation:

14 An example of the graphical output of ESCAPE: an assumed release of chlorine from a ruptured pipe in a container vessel. Input data for this case Legend for concentrations Map Genimap Oy

15 The model is directly applicable for these substances Acetone Chlorine Methane Acetonitrile Cumene N-butane Acrylic acid Ethane N-pentane Acrylonitrile Ethylene oxide Phosgene Ammonia Freon 12 Propane Benzene Hexane Propylene oxide Bromine Hydrogen cyanide Sulphur dioxide Butadiene Hydrogen fluoride Sulphur trioxide Butane Hydrogen sulphide Toluene Carbon disulphide Isobutane Vinyl chloride Carbon tetrachloride Methanol Additional species can be added.

16 Evaluation of ESCAPE against discharge trials using liquefied ammonia and sulphur dioxide (Sweden, 1982 and 1984). The Swedish National Defence Research Institute conducted ten ammonia field trials in Landskrona, Sweden in April The objective: study the flow of pressurized ammonia through pipes when released from the liquid phase of a vessel. Measurements: tank temperature and pressure, pipe exit pressure and mass flux for the ammonia trials. and five sulphur dioxide field trials in Skelleftehamn, Sweden in August The objective: measure the mass flow rate of SO 2 through an aperture and a pipe when released from the liquid space. Measurements: tank temperature and pressure, pipe exit pressure and mass flux for the sulphur dioxide trials. Refs.: Nyrén et al., 1983; Nyrén and Winter, 1983, 1986.

17 Mass flux error (%) Evaluation of the liquid and two-phase outflow models Of ESCAPE against the discharge trials (Sweden, 1982 and 1984) + 10 % Mass flux deviation (%) - 10 % ammonia, L = m ammonia, L = m -8 sulphur dioxide, L = 2 m sulphur dioxide, L = 0 m Vessel pressure (kpa) Vessel pressure (kpa) -> The relative uncertainty of the discharge modelling compared with data is less than 10 % The deviation of predicted and measured mass flux in % in the ammonia and sulphur discharge trials, against vessel pressure in kpa. L = pipe length.

18 Evaluation of ESCAPE against the FLADIS dispersion trials Experiments on continuous releases of liquefied ammonia were carried out in the project FLADIS Field Experiments funded by EU (Nielsen et al., 1994 and 1997; Nielsen and Ott, 1996), at Landskrona in The objective: study dispersion in the jet stage, the heavy plume and passive dispersion. Measurements: concentration was measured on arcs of sensors distributed across the plume at distances of 20, 70 and 240 m downwind from the source; three field campaigns with a total of 27 trials were conducted, of which the data of 16 has been prepared for distribution.

19 Modelled concentration (mole-%) Evaluation of ESCAPE against the FLADIS field trials 5 Pointwise scatter, N = Modelled concentration Trial 16 Trial Observed concentration (mole-%) Observed concentration Scatter plot of point-wise mean concentration for the FLADIS trials 16 and 24.

20 Evaluation of ESCAPE against the Thorney Island field trials The Heavy Gas Dispersion Trials at Thorney Island were organized by the Health & Safety Executive (UK) and were carried out between 1982 and 1984 (McQuaid and Roebuck, 1985; McQuaid, 1985 and 1987). The objective: study the dispersion of fixed-volume, isothermal clouds. Measurements: dose and arrival and departure times of the cloud were measured on arcs of sensors distributed across the cloud at distances of 100, 200, 220, 300, 350, 400, 450, 500, 600, 700 m downwind from the source. three continuous release trials, which divided into two phases. - phase I: 6 trials on uniform, unobstructured ground. - phase II: 10 trials in the presence of obstacles. the release gas was a mixture of dichlorodifluoromethane (CCl 2 F 2 ; freon-12) and nitrogen (N 2 ).

21 Downwind distance (m) An example of the evaluation of ESCAPE against the Thorney Island field trials, instantaneous releases Thorney Island, trial visual observations this study Time (s) The cloud centroid position against time as determined visually from the overhead photographs taken from the Thorney Island trial 008 (Prince et al., 1985) and predicted by the ESCAPE model.

22 Cloud height (m) Comparison of the predictions of ESCAPE and the visual observations Houston, Texas, 1976 Pasquill E NH3 u = 2 m/s m = kg T = 10 C 500 t = 1 min C max = 7700 mg/m Downwind distance (m) t = 0 min 3 C max = mg/m m A photograph taken about one minute after the Houston tanker crash (Fryer and Kaiser, 1979).

23 The automated combined use of ESCAPE and measurement data in a previous research project (TiTiMaKe) User interface TEKES Master server The system includes: Rescue services sensor network FMI dispersion computations Aalto population models Univ. Eastern Finland master server Visualisation tools for the end user Sensors Dispersion Population TiTiMaKe: Development of modelling methods for situational awareness ToMoVaKe: Open Platform For Environmental Monitoring ESCAPE dispersion modelling visualized. ToMoVaKe user interface Dimenteq Oy 2011.

24 The planned ESCAPE net application The system provides results for various users (top row) The core application includes ESCAPE combined to on-line meteorological modelling Met. duty officer A distributed system User #1 User #nn. (cf. TiTiMaKe) Harmonie HIRLAM LAPS.. Met. data extractor Core ESCAPE dispersion model

25 Evaluation of major fires Another model is available, called BUOYANT (Dispersion from Strongly Buoyant Sources) The dispersion of gases and particles released in major fires Includes treatments both for the plume rise, and larger scale dispersion Model output includes, e.g., concentrations of pollutants near ground level Can be used on a PC Reference: Kukkonen, J., Nikmo, J., Ramsdale, S.A., Martin, D., Webber, D.M., Schatzmann, M. and Liedtke, J., Dispersion from strongly buoyant sources. In: Gryning, S.-E. and Batchvarova, E. (eds.), Air Pollution Modeling and its Application XIII, Kluwer Academic/Plenum Publishers, pp

26 The results so far, and final expected results More accurate and reliable modelling tool for rescue services (2013) the refined model is based on the state-of-the-art science - done initial results of model evaluation look promising - done the model will be thoroughly evaluated using available measured data: A more user-friendly and versatile model (2014) less technical work required from the model user use of the best available meteorological information on-line use of the weather models, or measured values possibly, global availability of meteorological data The model will work in various information technology environments (2015) take into account all relevant environments avoid complications caused by different information tech. systems using the model over the net (possibly, via a mobile phone) possibly, use the VIRVE network (radio network of the authorities) for disseminating the dispersion maps and other information

27 Thank You

28 The propability of accident Consequence analysis Release Source term Atmospheric dispersion Consequence Risk

29 The state-of-the-art of source term models 1. Liquid pool models and two-phase jet models fairly good models available 2. Source terms of catastrophic releases only simple models available, challenging task 3. "Semi-instantaneous" releases no models available

30 Future research on heavy gas dispersion modelling thermodynamical effects the influence of complex terrain and obstacles statistical fluctuations time-dependent releases

31 Plume Cloud

32 The results of ESCAPE Dispersion diagram The height of gas cloud or plume The average concentration The temperature of gas cloud or plume The density of gas cloud or plume Tabulated results of concentration Total dose Dose in a minute Tabulated results of doses Toxicology and flammable levels

33 Box model cloud representation z Ur x Wind direction z y R L h x H ho Lo y Cloud shape for instantaneous release Plume shape for continuous release

34 Pressure (kpa) The saturation vapour pressure for some toxic and flammable substances (Kukkonen, Dissertationes No 34, The Finnish Society of Sciences and Letters). Excess of pressure (bar) NH Cl C 3 H 8 SO HF Temperature ( C)

35 Height of gas cloud (m) Cl 2 Continuous release G = 6.1 kg/s Pasquill B 3 m/s Pasquill D 3 m/s Pasquill D 8 m/s Pasquill E 2 m/s Pasquill D 5 m/s Pasquill F 2 m/s ,000 Downwind distance (m) The predicted height of the gas cloud in varying meteorological conditions (Kukkonen and Savolainen, Publ. on Air Quality 4, Finnish Meteorological Institute).

36 Mass flux (kg/s) 10 8 Release through pipe Length of pipe = 2.0 m Diameter of aperture = 40 mm Ammonia Chlorine Propane Sulphur dioxide Hydrogen fluoride Temperature ( C) The mass flux through a pipe from the liquid space of the container against the storage temperature (Kukkonen, Dissertationes No 34, The Finnish Society of Sciences and Letters).

37 Mass flux density (kg/s/cm 2 ) Release through pipe Length of pipe = 2.0 m Diameter of aperture = 40 mm Propane Chlorine Ammonia Sulphur dioxide Hydrogen fluoride Temperature ( C) The mass flux through a pipe from the liquid space of the container against the storage temperature (Kukkonen, Dissertationes No 34, The Finnish Society of Sciences and Letters).

38 Mass flux (kg/s) 10 8 Cl2 Temp. = +15 C 50 mm mm 30 mm Diameter = 20 mm Length of pipe (m) The mass flux through pipe from the liquid space of the container against the length of pipe (Kukkonen, Dissertationes No 34, The Finnish Society of Sciences and Letters).

39 Effects of ammonia Concentration Time of Symptoms Injurties mg/m 3 influence Noticeable odour 70 Light irritation of nose Irritation of mucous membrane h Irritation of throat, Light injuries eyes and nose, cough 500 Flowing of tears Rather serious injuries h Damages in lugn Serious injuries h Swelling of the throat May be lethal min Swelling of the throat Death

40 Effects of chlorine Concentration Time of Symptoms Injuries mg/m 3 influence Light odour h Noticeable odour Irritation of the mucous membrane 30 2 h Coughing Light injuries min Suffocating cough Rather difficult injuries min Suffocation cough Rather difficult injuries min Serious injuries 3000 Suffocation Death

41 Distance (m) Validation of DENZ model (1/4) DENZ Thorney Island Trial no 5 Pasquill B u = 4.6 m/s 30 This study Experimental Time (s) The distance of the cloud centroid from source against time (Kukkonen and Nikmo, J.Hazard.Mater. 31, ).

42 Distance (m) Validation of DENZ model (2/4) Thorney Island Trial no 7 Pasquill E u = 3.2 m/s This study 30 DENZ Experimental Time (s) The distance of the cloud centroid from source against time (Kukkonen and Nikmo, J.Hazard.Mater. 31, ).

43 Distance (m) Validation of DENZ model (3/4) Thorney Island Trial no 8 Pasquill D u = 2.4 m/s DENZ This study Experimental Time (s) The distance of the cloud centroid from source against time (Kukkonen and Nikmo, J.Hazard.Mater. 31, ).

44 Cloud speed (m/s) Validation of DENZ model (4/4) 6 5 Thorney Island experimental data model prediction Wind speed (m/s) The computed and measured cloud speeds against the measured wind speed at 10 m height (Kukkonen and Nikmo, J.Hazard.Mater. 31, ).

45 Model equations (POOL) Volume discharged: Pool volume: Pool temperature: Mass vaporised: dv dt dv dt d S S WA c V dt A Q WL Ts T c S dt dm dt WA A r 2 W ( T) u W( u z, Sc, R z, p ( T) p ) * * o o s a Q( T, t) conducted convected radiated W = evaporation rate A = area of pool c = spec. heat capacity of contaminant r = liquid density of contaminant Q = heat flux density into the pool L = latent heat of evaporation T s = temperature of source discharge

46 Performance evaluation of ESCAPE consequence analysis model Liquid and two-phase outflow models Measured vessel condition, pipe exit pressure and mass flux for the ammonia trials in Landskrona, Sweden (Nyrén et al., 1983). S = short pipe (2136 mm), L = long pipe (3636 mm). Trial Tank temperature ( C) Tank pressure (kpa) Exit pressure (kpa) Mass flux (kg s -1 ) S S S S S L L L L L

47 Performance evaluation of ESCAPE consequence analysis model Liquid and two-phase outflow models Measured temperatures of the tank liquid and time averages of tank pressures, pipe exit pressures and mass fluxes for the sulphur dioxide discharge trials in Skelleftehamn, Sweden (Nyrén and Winter, 1986). Trial Tank temperature ( C) Tank pressure (kpa) Exit pressure (kpa) Mass flux (kg s -1 ) P P A A A

48 Performance evaluation of ESCAPE consequence analysis model Liquid and two-phase outflow models Trial Mass flux measured (kg s -1 ) modelled (kg s -1 ) error (%) S S S S S L L L Modelled mass fluxes q and their errors,100 q modelled q measured 1, for the ammonia (Nyrén et al., 1983) and sulphur dioxide (Nyrén and Winter, 1986) discharge trials. L L P P A A A

49 Performance evaluation of ESCAPE consequence analysis model Continuous releases Performance measures for the FLADIS trials 16 and 24, where the observed (C o ) and predicted (C p ) point-wise mean concentrations (mole-%) are compared. trial max C o max C p mean C o mean C p FB NMSE MG log 10 (VG) R FAC

50 Jatkuvat päästöt Laippa- ja tiivistevuodot Putkivuodot vuodot venttiilin kautta putken katkeaminen Vuodot säiliön seinämästä 8/30/

51 Hetkelliset päästöt Esim. säiliön repeäminen Päästön lyhyt kesto Räjähdyksenomainen Pahin mahdollinen tapaus Seurauksena voi olla BLEVE (Boiling Liquid Expanding Vapour Explosion) 8/30/

52 Savukaasut ilmakehän virtaukset (tuuli ja turbulenssi) Ilmaa raskaammat kaasut painovoima termodynamiikka ilmakehän virtaukset Kaksi-faasisuihkut liikemäärä termodynamiikka tuuli 8/30/

53 z u h 2 h u Kaasupilven etenemisnopeus = tuulen nopeus kaasupilven keskikorkeudella u c u h 2 8/30/

54 Pilven ja vanan yksinkertaistettu kuvaus z Ur x Tuulen suunta z y R L h x H ho Lo y Kaasupilvi Kaasuvana 8/30/

55 ESCAPE -ohjelman tuloksia Leviämiskuvio Kaasupilven tai -vanan korkeus Kaasupilven tai -vanan korkein maanpintapitoisuus Kaasupilven tai -vanan lämpötila Taulukoituja tuloksia pitoisuuksista BLEVE (paineaallon leviämiskuvio) Toksikologiset tiedot ja syttymisrajat 8/30/

56 Ilmatieteen laitoksen palvelut kemikaalionnettomuuksien varalta Leviämisselvitykset laitoskohtaiset selvitykset teollisuudelle selvitykset viranomaisille Leviämismalliohjelma ESCAPE käyttäjinä viranomaisia Palvelut akuutissa onnettomuustilanteessa Etelä-Suomen aluetoimistoissa ja keskustoimipaikassa päivystys ympäri vuorokauden: säätiedot välittömästi leviämisarvio suuronnettomuuksissa Ilmanlaatuosastolta 8/30/

57 Mallien ja tulosten soveltaminen Viranomaisten pelastuspalvelu Teollisuuden turvallisuusanalyysi Teollisuuslaitosten lupamenettely ja tarkastus Tapahtuneiden onnettomuuksien analysointi Mallilaskelmat ovat hyödyllisimpiä varauduttaessa ennalta onnettomuustilanteisiin. 8/30/

58 Leviämisarvioiden soveltamiseen akuuteissa onnettomuustilanteissa liittyy monia ongelmia Tilanteet ovat nopeita ja paikallisia Suurimmat ongelmat esiintyvät onnettomuuden lähialueella Pelastushenkilöstöllä on kova kiire Erilaisia aineita ja tilanteita on suuri määrä Riittäviä lähtötietoja arvioille ei useinkaan ole saatavilla 8/30/

59 Vaikutusten arviointi Lähtökohtana leviämislaskelmat Päästöjen torjunta sekä suojautumisen ja pelastustoimien vaikutus 1. Myrkylliset kaasut toksikologiset tiedot: vaikutus = f(aika,pitoisuus) 2. Syttyvät kaasut syttymisrajat palojen lämpövaikutukset räjähdysten paine- ja lämpövaikutukset 8/30/

60 Leviämismallien käyttö ja soveltuvuus Suunnittelu, koulutus, turvallisuusanalyysi Äkilliset onnettomuustilanteet Nopeita ja paikallisia tilanteita Suuronnettomuuksia esiintyy kerran vuodessa Tulipalo-onnettomuuksien arvioimiseksi on omat mallinsa Maaston vaikutus 8/30/

61 Ilmaa raskaampien kaasupilvien leviämismallien kehittäminen Termodynamiikka ja aerosoli-ilmiöt Maastonmuotojen ja esteiden vaikutus leviämiseen Ajalliset pitoisuuden vaihtelut Leviäminen stabiilissa, heikkotuulisessa tilanteessa 8/30/

62 Vaarallisten aineiden kuljetukset maassamme (1982) Kuljetusluokka Maantie Rautatie Kokonaismäärä (milj. tonnia) 8.6 Mt 4.0 Mt 1. Räjähdystarvikkeet 0.1 % 0.2 % 2. Kaasut 1.4 % 9.6 % 3. Palavat nesteet 82.8 % 61.2 % 4. Helposti syttyvät aineet 2.9 % 17.8 % 5. Sytyttävästi vaikuttavat aineet 0.5 % 2.2 % 6. Myrkyt 0.4 % 3.5 % 7. Syövyttävät aineet 12.5 % 5.5 % (Lähde: Lautkaski, 1986) 100 % 100 % 8/30/

63 Tieliikenteessä kuljetettujen vaarallisten aineiden määrät (1992) Kuljetusluokka Osuus kokonaismäärästä (%) Muutos vuodesta 1987 (%) Kokonaismäärä 9.7 milj. tonnia 1. Räjähdystarvikkeet Kaasut Palavat nesteet Helposti syttyvät aineet Sytyttävästi vaikuttavat aineet Myrkyt Syövyttävät aineet (Lähde: Liikenneministeriö) 100 8/30/

64 Maailman pahimpia onnettomuuksia Paikka Aine Vuosi Kuolleet Vahingoittuneet Bhopal, Intia metyyli-isosyanaatti 1984 > 2500 tuhansia Sao Paolo, bensiini Brasilia St. J. Ixhuatepec, nestekaasu Meksiko Novosibirsk, tuntematon Neuvostoliitto Los Alfaques, propyleeni Espanja Tacoa, Venezuela öljy Xilatopec, nestekaasu Meksiko Osaka, Japani nestekaasu Gahri Dhada, maakaasu Pakistan Huimanguille, Mexico nestekaasu /30/

65 Suomen pahimpia kemikaalionnettomuuksia Paikka Aine Vuosi Kuolleet Vahingoittuneet Lapua räjähdysaine Rauma kloori > 100 Imatra rikkidioksidi Nivala rikkihappo Nilsiä kloori Uimaharju kloori Pietarsaari kloori Äetsä kloori /30/

66 Myrkyllisten kaasujen ominaisuuksia Kloori Ammoniakki Rikkidioksidi Kiehumispiste -34 C -33 C -10 C Nesteen tiheys (vesi=1) Kaasun tiheys (ilma=1) Tilavuussuhde (kaasu/neste) Höyrystymislämpö (vesi=1) Liukenee veteen huonosti erittäin hyvin hyvin 8/30/

67 Ammoniakin vaikutukset Pitoisuus Altistusaika Oireet Vahingoittuminen mg/m Haju tuntuu 70 Lievä nenän ärsytys Limakalvojen ärtymistä h Nenän, nielun ja silmien Lieviä vammoja ärsytys, yskittää 500 Kyynelvuotoa Lievää vaik. vammoja h Keuhkovammoja Vaikeita vammoja h Kurkunpään turvotus Hengenvaara min Kurkunpään turvotus Kuolema 8/30/

68 Kloorin vaikutukset Pitoisuus Altistusaika Oireet Vahingoittuminen mg/m Haju voi tuntua h Haju tuntuu Limakalvojen ärtymistä 30 2 h Yskittää Lieviä vammoja min Tukahduttava yskä Lievää vaik. vammoja min Tukahduttava yskä Lievää vaik. vammoja min Vaikeita vammoja 3000 Tukehtuminen Kuolema 8/30/

69 Paine(kPa) Ylipaine(bar) NH Cl CH 38 SO HF Lämpötila( C) Kylläisen höyryn paine sekä kyllästystilan vallitessa säiliössä vallitseva ylipaine eräille myrkyllisille ja syttyville kaasuille. 8/30/

70 Kasuvanakorkeus(m) 10 Cl 2 Jatkuvapästö 80 G=6.1kg/s 60 Pasquil B 3m/s Pasquil D 8m/s Pasquil D 5m/s Pasquil D 3m/s Pasquil E 2m/s Pasquil F 2m/s ,0 Etäisys(m) Kaasuvanan korkeus etäisyyden mukana eräissä säätilanteissa (Kukkonen ja Savolainen, 1988, Ilmansuojelun julkaisuja 4, Ilmatieteen laitos). 8/30/

71 Propani 30 Pasquil D T=+15 C 20 u=5m/s L=1.72m 10 D=74m 0 Etäisys(m)UFL s -20 Sytymisrajat propanile: UFL=184g/m 3 LFL=42g/m 3 LFL 6s Etäisys(m) Propaanin (nestekaasun) putkivuoto rautatiekuljetus-säiliöstä. Massavirta purkausaukossa on 21 kg/s. 8/30/