David Jeltes, ERICO, USA - Welcome

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Fire Sprinkler Earthquake Protection – Sway Bracing
Abstract
• Earthquake sway bracing for fire
sprinklers will become normative in the
EN12845 Annex
• Building structures are protected against
earthquakes and so should the life safety
system of fire sprinklers
Abstract
• Fire sprinkler protection provided thru:
– Joint flexibility
– Proper clearances
– Sway Bracing
• Sway bracing consists of:
– Lateral
– Longitudinal
– 4Way
Abstract
• Brace design is based on the amount of
sprinkler pipe weight within a zone of
influence (ZOI) for a given horizontal
seismic load (“g” force)
– Requires calculations and submittals to
AHJ’s showing brace meets design loads
Abstract
• Brace assembly strength is limited to the
load capacity of the weakest component
– Requires 3rd party load testing & certification
Today’s Presentation
• Importance of bracing fire sprinklers
• Brace assembly components
• General rules for brace placement
Importance of Bracing
Fire Sprinklers
FM Global - Understanding the Hazard
“Lack of Earthquake Bracing on Sprinkler System”
10 Year Period (FM Global)
• 561 earthquakes worldwide
• $315 million (USD) in damages facilities
• $560,000 (USD) average loss
• 50% of average loss is due to sprinkler
system failure
How Damage Occurs
• Building movement is different than the
fire sprinkler pipe
• Unbraced fire sprinklers damage may
occur by:
– Hitting walls, suspended ceilings or other
building systems
– Fittings break due to twisting
– Couplings can separate or leak during
excessive bending, rotation or movement
Additional Concerns
• Protecting against loss from fire or water
leakage is a critical towards recovery from
an earthquake
• Time for water leak discharge to fill a 14 ft
x 14 ft (4.3m x 4.3m) room to depth of 1
foot (30cm) based on 50 psi (3.4 bar):
Pipe Diameter
(in)
(mm)
1/2
12
1
32
1 1/2
40
2
50
4
100
6
150
Time
(minutes)
37
8.1
4.0
2.7
1.5
1.3
Ways to Avoid Sprinkler Damage
• Bracing
• Flexibility
• Clearance
• Other Considerations
– Brace suspended ceilings
– Weak brace and/or hanger attachments
– Anchoring of equipment, tanks & racks
Costs to Brace
• 3 – 4% if installed with the sprinkler
system
• Retrofit costs vary widely from an
estimated $100 - $500 USD per brace
location
Importance of Sprinkler Bracing - Summary
• Critical after earthquake protection
against:
– Water leaks
– Fires
• Decreases loss of:
– Property
– Function / use of facilities
• Increases life safety
Brace Assembly Components
Sway Brace Components
Structure
Attachment
Brace
Brace Clamp
Structural Attachments
CSBUNIV – Universal Structural
Structural Attachments
CSBBARJ – I-Beam Attachment
Structural Attachments
CSBIB – Adjustable
I-Beam Attachment
Structural Attachments
CSBMA – Multi Attachment
Brace Clamps – Lateral Only
CSBQIKCL – Quick Grip Jr
CSBQG – Quick Grip
Brace Clamps – Lateral & Longitudinal
CSBEZU and CSBSTU
Universal Brace Clamp
General Rules
For
Brace Placement
Lateral Bracing
Lateral Bracing
• What:
– Feed and cross mains (any size)
– Branch and other piping > 2 ½” (65mm)
diameter
• Where:
– 40 ft o.c. (12m) maximum spacing
– On the last length of pipe at the end of a main
– Within 6 ft (1.8m) of the end of the pipe
Lateral Bracing
Lateral Bracing
• Can act as longitudinal brace if installed
within 2 ft (0.6m) of piping braced
longitudinally
Note that Pipe A Diameter > Pipe B Diameter
Longitudinal Bracing
Longitudinal Bracing
• What:
– Feed and cross mains (any size)
– Branches > 2 ½” (65mm) diameter
• NFPA 13  Not Required
• FM DS 2-8  Required if longer than 40 ft (12.2m)
• Where:
– 80 ft (24.2m) o.c. maximum spacing
– Within 40 ft (12.2m) of the end of the pipe or
change in direction
Longitudinal Bracing
Longitudinal Bracing
• Can act as a lateral brace if installed
within 2 ft (0.6m) of piping braced laterally
Riser Bracing
• Riser tops exceeding 3 ft (0.9m) in length
• Maximum Spacing = 25 ft (7.6m) o.c.
Thank You
Any Questions??
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