Fire and explosion, 3-5 tons of ammonium nitrate. Resulting in 26 casualties including 18 firemen, 82 houses with structural damage, metallic beam missiles found up to 500 meters from epicenter.

1. Accident (explosion succeeding to fire) at St
ROMAIN en JAREZ (France), 2 October 2003
(In confidence)
Contributors :
M-A KORDEK
C. MICHOT
G. MARLAIR
Approvals Division

2. Location of accident and time schedule of scenario
• Saint-Romain en Jarez,
 village located about 30 km from St-Etienne (France, Loire
Department), about 1000 inhabitants
• 2 October 2003 , timetable of events
 16h02 : fire brigade called for a farmhouse fire,
 16h24 : arrival of fire brigade : facing a warehouse fire
 17h12 : explosion occurrence
• Measures taken in the emergency
• 3 October : safety perimeter implemented by authorities after
the explosion (300 m at first, reduced to 100m by 6 October
morning)
• 5 October 2003 , end of evening : fire declared
extinguished

3. Casualties and structural damage
 26 casualties including 18 firemen (3 of which suffering
injuries compromising life), 3 policemen et 5 civilians
 82 houses suffering structural damage of varying
severity

4. View of building of origin before the accident

5. View of building ruins after the explosion

6. INERIS involvement into
first response to the “crisis”
• Arrival on site on 3 October 2003, by16:30
• Damage inspection and recording of observations,
compiling information, providing on-site support to
emergency teams being there to manage the emergency,
….
• Presence on site maintained up to 7 October.

7. First statements from damage observations and records
• 30 (among higher number of ) damage single inputs
(observations) being used in the first analysis regarding
the characterization of the explosion strength,
 about location of nearest dwellings : 60 m far from the warehouse,
 damage observed as far as 650m far from the warehouse
 significant damage limited to some 300m to 600 m
 very serious damage to structures : up to 150m

8. Artistic view
of the
accident
scene after
the
explosion
(R. Dosne)
greenhouses
Metallic Beam
element missiles
found up to 500
m
Crisis management
Control room installed in townhouse 4 helicopters
used
Advanced medical
teams
Fire hydrant
Evacuation
means
(12 vehicles)
Fire engine
destroyed

9. Schematic view of warehouse and stockpiles of materials, red spots indicating
firemen location and other operational circumstances when injured by the blaze
AN fertilizers storage
3 t , big bags
Presumed origin of
fire
on upper level
(hay ?)
Some 3000 plastic
boxes in piles Plastic
boxes
Flat on
1st floor
Cold storage area filled
with potatoes in boxes
Site access route

10. Gymnasium - 100 m

11. Estimation of ‘ TNT equivalent ’ of the explosion from
observed damage
Pressure effects deducted from observed damage, then use of charts of
‘hemispheric loading’ : referring to methodology used for the
investigation of the Toulouse accident,
Result : 80 kg to 160 kg of TNT equivalent
if detonation related to AN, then quantity in agreement with observation
is within the range :
160 kg to 533 kg
with proportionality rule from Circular of 21 January 2002:
1600 to 5330 kg of material, initially.
Notice : estimated quantity of AN fertilizer : 3 to 5 tons.

12. On the missile effect
• 26 missile elements identified
 wall lining elements : no use in the analysis as they have
experienced significant deformation before explosion due to the
preceding fire,
 concrete scraps,
 structural elements :
• beam type ‘IPN 120’, 6 m of length, 70 kg of weight,
• beam type ‘IPE 240’, 6m of length, 200 kg of weight,
• sectional steel pieces,
projection of scraps up to 800m,
IPE 240 beam elements : displaced some 250m
IPN 120 beam elements : displaced 310m to 350 m

13. Elements of wall linings

15. Beam type IPN 120 : located at 180 m from explosion area

16. Beam type ‘IPN 120’ : 330 m behind the chapel

17. Crater
(Plausibly) explosion-induced crater observed, located below the
concrete slab on which big-bags (500 kg each ) of products were stored

18. Open Literature available to date limited to :
a) Numerous Press releases
b) René Dosne, “Explosion of AN fertilizer storage in a farmhouse
building”, Face au Risque n°399, January 2004 (In French), 26-29
c) Le Sapeur-pompier magazine, n° 951, November 2003 (In French),
p15-17