Samenvatting brandveiligheid in gebouwen
Inhoud
Fire dynamics........................................................................................................................................... 5
What is fire? ........................................................................................................................................ 5
Fire-some basics .................................................................................................................................. 5
Thermodynamics ............................................................................................................................. 7
Heat feedback loop.......................................................................................................................... 7
Free fire plume .................................................................................................................................... 8
Fire development in enclosures .......................................................................................................... 8
Fire development in enclosures – heat ............................................................................................... 8
The ISO curve..................................................................................................................................... 12
Passive fire protection ........................................................................................................................... 13
Material properties............................................................................................................................ 13
Compartmentation: Principle and critxeria ....................................................................................... 17
Compartmentation: Reaction to fire ................................................................................................. 18
Compartmentation: Fire resistance ................................................................................................... 19
Compartmentation: Some Examples ................................................................................................. 20
Eurocodes .......................................................................................................................................... 20
Behaviour of structures ..................................................................................................................... 21
Smoke dynamics .................................................................................................................................... 21
What is smoke? ................................................................................................................................. 21
Free smoke plume ............................................................................................................................. 22
The effect of an enclosure: ceiling ..................................................................................................... 23
The effect of an enclosure: spill plumes ............................................................................................ 24
Other driving forces ........................................................................................................................... 25
Smoke and heat control: natural and mechanical ventilation............................................................... 26
Flows through openings .................................................................................................................... 26
Vertical ventilation (natural/mechanical) .......................................................................................... 27
Horizontal ventilation: tunnels .......................................................................................................... 29
Horizontal ventilation: car parks........................................................................................................ 29
Smoke and heat control: systems .......................................................................................................... 29
Compartmentation ............................................................................................................................ 29
Pressurization/de-pressurization....................................................................................................... 29
Positive pressure ventilation ............................................................................................................. 31
Smoke dilution ................................................................................................................................... 31
1
, Natural ventilation ............................................................................................................................. 31
Mechanical ventilation ...................................................................................................................... 32
Smoke filling ...................................................................................................................................... 32
Smoke extraction ............................................................................................................................... 33
Air curtains ........................................................................................................................................ 33
Water curtains ................................................................................................................................... 33
Fire suppression..................................................................................................................................... 34
The effect of water ............................................................................................................................ 34
Sprinklers ........................................................................................................................................... 34
Water mist ......................................................................................................................................... 34
Other suppression agents.................................................................................................................. 35
Firefighting......................................................................................................................................... 35
Fire Safety Strategy ................................................................................................................................ 35
Wat willen we bereiken? ................................................................................................................... 35
Hoe krijgen we een ‘brandveilig’ gebouw? ....................................................................................... 35
Waar past de brandveiligheidsstrategie in het ontwerpproces?....................................................... 36
Verantwoording BVS .......................................................................................................................... 36
Fire (Safety) Engineering ................................................................................................................... 37
Bijzonder onderwerpen ..................................................................................................................... 37
Human Behaviour .................................................................................................................................. 37
General .............................................................................................................................................. 37
Evacuation analysis ............................................................................................................................ 38
Design of evacuation ......................................................................................................................... 39
Conclusion ......................................................................................................................................... 40
Regelgeving in België ............................................................................................................................. 40
Wat is recht? ...................................................................................................................................... 40
Overheden ......................................................................................................................................... 40
Bevoegdheden................................................................................................................................... 41
Vormen .............................................................................................................................................. 41
Bekendmaking ................................................................................................................................... 41
Hiërarchie .......................................................................................................................................... 41
Koninklijk Besluit – punt 1: inplanting en toegangswegen ............................................................ 42
Reactie bij brand van gevels .......................................................................................................... 42
Koninklijk Besluit – punt 3 ............................................................................................................. 43
Compartimentering en evacuatie .................................................................................................. 44
Indeling industriegebouwen in klassen ......................................................................................... 46
2
, Evacuatie (ASET>RSET) .................................................................................................................. 46
Fire Detection systems .......................................................................................................................... 50
CE CPR................................................................................................................................................ 50
EN 54 ................................................................................................................................................. 50
NBN S21-100...................................................................................................................................... 50
Fire departement............................................................................................................................... 50
Client safety policy............................................................................................................................. 50
Insurance ........................................................................................................................................... 50
Legislation.......................................................................................................................................... 51
Elements of a fire detection system .................................................................................................. 51
Fire supression....................................................................................................................................... 55
Extinguishing fire ............................................................................................................................... 55
Classification of fire ........................................................................................................................... 55
Start of extinguishing......................................................................................................................... 56
Clean agents = gasblussing ................................................................................................................ 56
Inerte gassen ................................................................................................................................. 57
CO2 ................................................................................................................................................. 58
Halocarbonen ................................................................................................................................ 58
Sprinklers and watermist system....................................................................................................... 59
Sprinkler systeem .......................................................................................................................... 59
Watermist ...................................................................................................................................... 61
Foam and powder systems ................................................................................................................ 62
Wanneer gebruiken we foam? ...................................................................................................... 62
Poeder ........................................................................................................................................... 62
Condensed aerosol extinguishing systems .................................................................................... 62
Fire resistance & structural fire engineering ......................................................................................... 63
Nominale branden ............................................................................................................................. 63
Brandweerstand ................................................................................................................................ 63
Performantie van structuren bij brand .............................................................................................. 63
Risico’s en oppurtuniteiten................................................................................................................ 66
Firefighting tactics ................................................................................................................................. 66
Belgian fire service ............................................................................................................................ 66
The sequence of events ..................................................................................................................... 66
Case study: cherry road ..................................................................................................................... 67
First rule of thumb ............................................................................................................................. 67
Tactical options .................................................................................................................................. 67
3
,4
,Fire dynamics
What is fire?
Necessary ingredients: fire triangle
• Oxidizer
o Zuurstof uit de lucht (concentratie = 21%)
• Heat
o Aansteking nodig, daarna heat flux van vlammen
o Vlamtemperatuur: 1000°C
• Fuel
o Alles dat brandbaar is
o Belangrijke binding met oxidizer
o Belangrijke binding met heat
Fire-some basics
• Verbranding: chemische reactie tussen brandbare soorten en zuurstof
o Meer afhankelijk van samenstelling en verdeling brandstof
o Verdeling brandstof: dikke balk vs tandenstokers
▪ Tandenstokers branden makkelijker door groter/meer oppervlak
o Explosieveiligheid: laagje poeder <-> poederwolk
• Brandstof: alles dat brandt (gas tot vaste stoffen)
• Vlam = gas fenomeen
o Verbranding vaste stoffen en vloeistoffen => omzetting naar gas
o Vloeistof: verdamping aan oppervlak
o Vaste stoffen: chemische ontbinding aan oppervlak = pyrolyse
▪ Mening: = soort van verdamping
▪ Pyrolyse warmte = warmte nodig om brand door te laten gaan
• Verdamping/pyrolyse = endotherm proces => 𝐿𝑣
o Latente verdampingswarmte/pyrolyse warmte = hoeveelheid energie nodig om 1kg
brandstof te pyrolyseren/verdampen (J/kg, kJ/kg, MJ/kg)
o Waar komt die vandaan?
▪ Free fire plume: vlammen
▪ Enclosed fire: vlammen, rooklaag, muur, plafond, andere objecten
Processen
• Fuel surface geeft warmte 𝑚̇∆𝐻𝑐 vrij naar
5
, o Vlam
o Omgeving
• Vlam geeft warmte terug door straling en convectie
• Fuel surface heeft vermogen 𝑚̇𝐿𝑣 om te pyrolyseren
• 𝑚̇∆𝐻𝑐 ≫ 𝑚̇𝐿𝑣 : brand groeit
• 𝑚̇∆𝐻𝑐 < 𝑚̇𝐿𝑣 : brand dooft uit
• 𝑚̇∆𝐻𝑐 = 𝑚̇𝐿𝑣 : steady state
• Air entrainment: aanzuigen & vermengen van zuurstof en brandbare gassen
o Ontstaan onderdruk aan onderzijde vlam (hogere temp -> lagere massadichtheid ->
gas stijgt -> zuiger effect -> onderdruk) => trekt zuurstof aan
Notaties
• 𝑚"̇: mass flow rate per unit area (kg/m²s)
• 𝑄"̇ 𝐹 : heat flux from flames per unit area (W/m²)
• 𝑄"̇ 𝐿 : heat losses per unit area (W/m²)
• 𝑚̇: mass flow rate (kg/s) (=𝑚”̇ ∗ 𝐴𝐹
• ∆𝐻𝑐 : heat of combustion (J/kg)
Flammability, ontvlambaarheid
• Fuel + Oxidizer -> Products
• Stoichiometrische omstandigheden: net genoeg oxidizer om alles te verbranden -> maximale
temperatuur
• Fuel lean: over-geventileerd, ‘brandstof-gecontroleerd’
o Lower flammability limit: onvoldoende brandstof om brand in gang te houden
o Vlammen zullen afkoelen door te veel aan zuurstof
• Fuel rich: onder-geventileerd, ‘ventilatie-gecontroleerd’
o Upper flammability limit: onvoldoende zuurstof om brand in gang te houden
6
Inhoud
Fire dynamics........................................................................................................................................... 5
What is fire? ........................................................................................................................................ 5
Fire-some basics .................................................................................................................................. 5
Thermodynamics ............................................................................................................................. 7
Heat feedback loop.......................................................................................................................... 7
Free fire plume .................................................................................................................................... 8
Fire development in enclosures .......................................................................................................... 8
Fire development in enclosures – heat ............................................................................................... 8
The ISO curve..................................................................................................................................... 12
Passive fire protection ........................................................................................................................... 13
Material properties............................................................................................................................ 13
Compartmentation: Principle and critxeria ....................................................................................... 17
Compartmentation: Reaction to fire ................................................................................................. 18
Compartmentation: Fire resistance ................................................................................................... 19
Compartmentation: Some Examples ................................................................................................. 20
Eurocodes .......................................................................................................................................... 20
Behaviour of structures ..................................................................................................................... 21
Smoke dynamics .................................................................................................................................... 21
What is smoke? ................................................................................................................................. 21
Free smoke plume ............................................................................................................................. 22
The effect of an enclosure: ceiling ..................................................................................................... 23
The effect of an enclosure: spill plumes ............................................................................................ 24
Other driving forces ........................................................................................................................... 25
Smoke and heat control: natural and mechanical ventilation............................................................... 26
Flows through openings .................................................................................................................... 26
Vertical ventilation (natural/mechanical) .......................................................................................... 27
Horizontal ventilation: tunnels .......................................................................................................... 29
Horizontal ventilation: car parks........................................................................................................ 29
Smoke and heat control: systems .......................................................................................................... 29
Compartmentation ............................................................................................................................ 29
Pressurization/de-pressurization....................................................................................................... 29
Positive pressure ventilation ............................................................................................................. 31
Smoke dilution ................................................................................................................................... 31
1
, Natural ventilation ............................................................................................................................. 31
Mechanical ventilation ...................................................................................................................... 32
Smoke filling ...................................................................................................................................... 32
Smoke extraction ............................................................................................................................... 33
Air curtains ........................................................................................................................................ 33
Water curtains ................................................................................................................................... 33
Fire suppression..................................................................................................................................... 34
The effect of water ............................................................................................................................ 34
Sprinklers ........................................................................................................................................... 34
Water mist ......................................................................................................................................... 34
Other suppression agents.................................................................................................................. 35
Firefighting......................................................................................................................................... 35
Fire Safety Strategy ................................................................................................................................ 35
Wat willen we bereiken? ................................................................................................................... 35
Hoe krijgen we een ‘brandveilig’ gebouw? ....................................................................................... 35
Waar past de brandveiligheidsstrategie in het ontwerpproces?....................................................... 36
Verantwoording BVS .......................................................................................................................... 36
Fire (Safety) Engineering ................................................................................................................... 37
Bijzonder onderwerpen ..................................................................................................................... 37
Human Behaviour .................................................................................................................................. 37
General .............................................................................................................................................. 37
Evacuation analysis ............................................................................................................................ 38
Design of evacuation ......................................................................................................................... 39
Conclusion ......................................................................................................................................... 40
Regelgeving in België ............................................................................................................................. 40
Wat is recht? ...................................................................................................................................... 40
Overheden ......................................................................................................................................... 40
Bevoegdheden................................................................................................................................... 41
Vormen .............................................................................................................................................. 41
Bekendmaking ................................................................................................................................... 41
Hiërarchie .......................................................................................................................................... 41
Koninklijk Besluit – punt 1: inplanting en toegangswegen ............................................................ 42
Reactie bij brand van gevels .......................................................................................................... 42
Koninklijk Besluit – punt 3 ............................................................................................................. 43
Compartimentering en evacuatie .................................................................................................. 44
Indeling industriegebouwen in klassen ......................................................................................... 46
2
, Evacuatie (ASET>RSET) .................................................................................................................. 46
Fire Detection systems .......................................................................................................................... 50
CE CPR................................................................................................................................................ 50
EN 54 ................................................................................................................................................. 50
NBN S21-100...................................................................................................................................... 50
Fire departement............................................................................................................................... 50
Client safety policy............................................................................................................................. 50
Insurance ........................................................................................................................................... 50
Legislation.......................................................................................................................................... 51
Elements of a fire detection system .................................................................................................. 51
Fire supression....................................................................................................................................... 55
Extinguishing fire ............................................................................................................................... 55
Classification of fire ........................................................................................................................... 55
Start of extinguishing......................................................................................................................... 56
Clean agents = gasblussing ................................................................................................................ 56
Inerte gassen ................................................................................................................................. 57
CO2 ................................................................................................................................................. 58
Halocarbonen ................................................................................................................................ 58
Sprinklers and watermist system....................................................................................................... 59
Sprinkler systeem .......................................................................................................................... 59
Watermist ...................................................................................................................................... 61
Foam and powder systems ................................................................................................................ 62
Wanneer gebruiken we foam? ...................................................................................................... 62
Poeder ........................................................................................................................................... 62
Condensed aerosol extinguishing systems .................................................................................... 62
Fire resistance & structural fire engineering ......................................................................................... 63
Nominale branden ............................................................................................................................. 63
Brandweerstand ................................................................................................................................ 63
Performantie van structuren bij brand .............................................................................................. 63
Risico’s en oppurtuniteiten................................................................................................................ 66
Firefighting tactics ................................................................................................................................. 66
Belgian fire service ............................................................................................................................ 66
The sequence of events ..................................................................................................................... 66
Case study: cherry road ..................................................................................................................... 67
First rule of thumb ............................................................................................................................. 67
Tactical options .................................................................................................................................. 67
3
,4
,Fire dynamics
What is fire?
Necessary ingredients: fire triangle
• Oxidizer
o Zuurstof uit de lucht (concentratie = 21%)
• Heat
o Aansteking nodig, daarna heat flux van vlammen
o Vlamtemperatuur: 1000°C
• Fuel
o Alles dat brandbaar is
o Belangrijke binding met oxidizer
o Belangrijke binding met heat
Fire-some basics
• Verbranding: chemische reactie tussen brandbare soorten en zuurstof
o Meer afhankelijk van samenstelling en verdeling brandstof
o Verdeling brandstof: dikke balk vs tandenstokers
▪ Tandenstokers branden makkelijker door groter/meer oppervlak
o Explosieveiligheid: laagje poeder <-> poederwolk
• Brandstof: alles dat brandt (gas tot vaste stoffen)
• Vlam = gas fenomeen
o Verbranding vaste stoffen en vloeistoffen => omzetting naar gas
o Vloeistof: verdamping aan oppervlak
o Vaste stoffen: chemische ontbinding aan oppervlak = pyrolyse
▪ Mening: = soort van verdamping
▪ Pyrolyse warmte = warmte nodig om brand door te laten gaan
• Verdamping/pyrolyse = endotherm proces => 𝐿𝑣
o Latente verdampingswarmte/pyrolyse warmte = hoeveelheid energie nodig om 1kg
brandstof te pyrolyseren/verdampen (J/kg, kJ/kg, MJ/kg)
o Waar komt die vandaan?
▪ Free fire plume: vlammen
▪ Enclosed fire: vlammen, rooklaag, muur, plafond, andere objecten
Processen
• Fuel surface geeft warmte 𝑚̇∆𝐻𝑐 vrij naar
5
, o Vlam
o Omgeving
• Vlam geeft warmte terug door straling en convectie
• Fuel surface heeft vermogen 𝑚̇𝐿𝑣 om te pyrolyseren
• 𝑚̇∆𝐻𝑐 ≫ 𝑚̇𝐿𝑣 : brand groeit
• 𝑚̇∆𝐻𝑐 < 𝑚̇𝐿𝑣 : brand dooft uit
• 𝑚̇∆𝐻𝑐 = 𝑚̇𝐿𝑣 : steady state
• Air entrainment: aanzuigen & vermengen van zuurstof en brandbare gassen
o Ontstaan onderdruk aan onderzijde vlam (hogere temp -> lagere massadichtheid ->
gas stijgt -> zuiger effect -> onderdruk) => trekt zuurstof aan
Notaties
• 𝑚"̇: mass flow rate per unit area (kg/m²s)
• 𝑄"̇ 𝐹 : heat flux from flames per unit area (W/m²)
• 𝑄"̇ 𝐿 : heat losses per unit area (W/m²)
• 𝑚̇: mass flow rate (kg/s) (=𝑚”̇ ∗ 𝐴𝐹
• ∆𝐻𝑐 : heat of combustion (J/kg)
Flammability, ontvlambaarheid
• Fuel + Oxidizer -> Products
• Stoichiometrische omstandigheden: net genoeg oxidizer om alles te verbranden -> maximale
temperatuur
• Fuel lean: over-geventileerd, ‘brandstof-gecontroleerd’
o Lower flammability limit: onvoldoende brandstof om brand in gang te houden
o Vlammen zullen afkoelen door te veel aan zuurstof
• Fuel rich: onder-geventileerd, ‘ventilatie-gecontroleerd’
o Upper flammability limit: onvoldoende zuurstof om brand in gang te houden
6
