fire load

1. FIRE AND LIFE SAFETY IN NBC
G C MISRA
gplmisra@yahoo.com
9868022790

2. WHAT DO WE DESIGN FOR?
THE CORE OBJECTIVE IS TO PROTECT
AGAINST THE HAZARD THAT MAY EXIST IN
ANY BUILDING DUE TO PRESENCE OF
VARIOUS LOADS AND ACCORDINGLY
NAMED.

3. DESIGNING FOR FIRE & LIFE SAFETY
Occupant Load-Life
Safety
Live Fire Load-
Property Protection
Dead Fire Load-
Structural Protection

4. HOW THE HAZARDS COME INTO PLAY?
 DUE TO ACCIDENTAL FIRE
 THREAT TO LIFE DUE TO HEAT & SMOKE
 DAMAGE TO PROPERTY DUE TO
BURNING
 DAMAGE TO STRUCTURE INCLUDING

5. CAN WE CREATE ENERGY?
NO
WHERE TO GET ENERGY FROM?
CONVERT SOME OTHER FORM OF ENERGY
WHAT IS THAT OTHER FORM?
CHEMICAL ENERGY

6. WHAT IS FIRE?
FIRE IS AN EXOTHERMIC
REACTION THAT TAKES PLACE
IN THE PRESENCE OF HEAT
AND OXYGEN TO CONVERT
CHEMICAL ENERGY OF FUEL
INTO HEAT ENERGY.

7. WHY DO WE IGNITE A FUEL?
TO GET HEAT
WHAT IS HEAT?
HEAT IS A FORM OF ENERGY
HOW TO GET HEAT ENERGY?
CONVERT SOME OTHER FORM OF ENERGY
WHAT ARE OTHER FORMS OF ENERGY?
CHEMICAL/ELECTRICAL/MECHANICAL/NUCL
EAR

8. WHAT IS THE SOURCE CHEMICAL ENERGY?
THEY ARE CHEMICALS
HOW CHEMICALS GIVE HEAT ENERGY?
THROUGH A CHEMICAL REACTION
DOES ALL REACTIONS GIVE HEAT?
NO
WHICH REACTIONS GIVE HEAT?
EXOTHERMIC REACTIONS

9. WHAT IS A FUEL?
FUEL IS A SOURCE OF CHEMICAL
ENERGY
EXAMPLES?
WOOD, PAPER, CLOTH,OILS, GAS
ETC.
CAN WE BURN STEEL?
NO
IS STEEL A FUEL?
ANY MATERIAL THAT CAN NOT

10. WHAT IS A LOAD?
LOAD IS THE WEIGHT OF FUEL
HOW MUCH IS THE FUEL LOAD IN A
ROOM IF IT HAS THE FOLLOWING:
 10 KG OF STEEL
 20 KG OF WOOD
 5 KG OF CLOTH
 2 LITERS OF PETROL
 3 KG OF PLASTICS

11. DO FUELS RELEASE SAME HEAT ENERGY WHEN
BURNED?
NO, DIFFERENT FUELS RELEASE DIFFERENT
AMOUNT OF HEAT ENERGY.
WHAT IS THIS HEAT ENERGY CALLED?
CALORIFIC VALUE OF FUELS
HOW IS THAT HEAT ENERGY MEASURED?
IT IS MEASURED IN JOULES PER UNIT
MASS [J/g]

12. CALORIFIC VALUE
Calorific value is the amount of heat
energy present in fuel and which is
determined by the complete combustion
of specified quantity at constant pressure
and in normal conditions. It is also called
calorific power. The unit of calorific value is
kilo joule per kilogram i.e. KJ/Kg.

13. CALORIFIC VALUE OF WOOD
THE CALORIFIC VALUE OF WOOD IS 17600
kJ/kg
WHAT DOES THIS MEANS?
THIS MEANS THAT IF ONE KG OF WOOD IS
BURNED COMPLETELY THEN 17600 kJ
HEAT ENERGY IS PRODUCED.

14. WHAT IS THE FIRE LOAD?
FIRE LOAD IS DEFINED AS THE TOTAL
AMOUNT OF HEAT ENERGY PRODUCED
BY BURNING THE ENTIRE FUEL PRESENT
IN AN AREA.
THIS IS EXPRESSED IN kJ/m2
[1 kJ= 0.24 k Cal = 0.95 x 10-3 BTU]

15. FIRE LOAD OF MATERIALS
FIRE LOAD OF MATERIALS : CELLULOSIC
(E.G. PAPER, CARDBOARD, WOOD),
PLASTIC, TEXTILE/FABRIC);
1. Wood 18.6 MJ/kg
2. Paper 17.0 MJ/kg
3. Plastic 22.1 MJ/kg
4. Textile 19.0 MJ/kg

16. WOOD EQUIVALENT [WE]
THIS MEANS THAT ALL FUELS ARE
EQUATED TO WOOD AND DETERMINED BY
DIVIDING THE CV OF FUEL BY CV OF
WOOD.
EXAMPLE:
THE CV OF WOOD IS 17.6 kJ/Kg AND CV OF
POLYSTER IS 22 kJ/Kg.
THUS, 1 Kg OF POLYSTER IS EQUIVALENT
TO 1.25 Kg OF WOOD IN TERMS OF HEAT
ENERGY.

17. HOW TO CALCULATE FIRE LOAD?
1. SELECT A ROOM
2. MEASURE THE LENGTH (m)
3. MEASURE THE WIDTH (m)
4. LIST THE NAMES OF ALL FUELS IN THE
ROOM
5. MEASURE THE WEIGHT OF EACH FUEL
6. NOTE THE CALORIFIC VALUE OF EACH

18. PREPARE A TABLE
1. WRITE SR. NO. IN COLUMN 1
2. WRITE NAME OF FUEL IN COLUMN 2
3. WRITE CALORIFIC VALUE IN COLUMN 3
4. WRITE TOTAL WEIGHT OF FUEL IN
COLUMN 4
5. WRITE TOTAL CALORIFIC VALUE OF
FUEL BY MULTIPLYING THE WEIGHT OF
FUEL [Kg] x CV
6. SUM TOTAL OF TOTAL CV OF ALL
FUELS
7. DIVIDE SUM TOTAL OF CV OF ALL

19. FIRE LOAD CLASSIFICATION
1. LOW FIRE LOAD
(up to 2,75,000. Kcal/m2)
2. MODERATE FIRE LOAD
(above 2,75,000 Kcal/m2 to 5,50,000 kcal/m2)
3. HIGH FIRE LOAD
(above 5, 50, 000 kcal/m2 to 11,00, 000
kcal/m2)

20. WHERE DO WE USE FL INFORMATION?
1. CLASSIFICATION OF OCCUPANCY
2. ESTIMATING THE FIRE GROWTH
POTENTIAL
3. ESTIMATING FIRE RESISTANCE
REQUIREMENTS
4. ESTIMATING WATER DEMANDS

21. OCCUPANCY CLASSIFICATION WRT FIRE
LOAD DENSITY (WE) [NBC 2005]
 RESIDENTIAL [A1 & A2]: 25 kg/m2
 RESIDENTIAL [A3 TO A5]: 25 kg/m2
 EDUCATIONAL & INSTITUTIONAL: 25
kg/m2
 ASSEMBLY & BUSINESS: 25-50 kg/m2
 MERCANTILE: UPTO 250 kg/m2
 INDUSTRIAL: UPTO 150 kg/m2
 STORAGE & HAZARDOUS: UPTO 500

22. CLASSIFICATION OF STRUCTURES
 TYPE I STRUCTURAL COMPONENTS: 4 Hrs
 TYPE II STRUCTURAL COMPONENTS: 3 Hrs
 TYPE III STRUCTURAL COMPONENTS : 2 Hrs
 TYPE IV STRUCTURAL COMPONENTS: 1 Hrs
THE FIRE RESISTANCE CAN BE CALCULATED WRT FOLLOWING
FACTORS :-
a) STABILITY
b) INTEGRITY
c) THERMAL INSULATION

23. FIRE RESISTANCE WRT FIRE LOAD
Wood and Fiber, 9(1), 1977, pp. 73-85, by the Society of Wood Science and
Technology

24. FIRE TEMPERATURE
The time-
equivalence
method creates a
relation between
the effects of
heating in structural
members caused
by natural fires and
those caused by
the ISO fire curve
(BS ISO834, 2014).