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Utility Issues with CSST Gas Piping
Long continuous runs
Few joints
Smaller installation crew
Faster installation time
Only simple hand tools required
No threading machines/mess
Safer interaction with structure
Advantages of CSST
Lightning protection system
Bonding of piping to grounding electrode system
Arc resistant protective jacket
Utility Issues with CSST Gas Piping
Protection from Lightning
Utility Issues with CSST Gas Piping
Total lightning strikes in
US per year: 43,500,000*
No house, equipment or
material safe from direct
lightning strike
Most claims from indirect
strikes
[*USPLN: 2005-2009]
Lightning Damage
Utility Issues with CSST Gas Piping
What are the root causes?
Changes in house
construction/size/location
Loss of metal piping
Loss of copper wire
for communications
Loss of metal conduit
for electric wiring
Utility Issues with CSST Gas Piping
Metallic appliance flue (instead of
brick/clay chimneys) which rise
above the roofline. Metal vent
acts like lightning rod not directly
connected to the electrical
grounding system.
Unintended Consequences
Utility Issues with CSST Gas Piping
Lightning does not discriminate. It seeks all pathways to ground.
It will damage all mechanical/electrical systems.
Utility Issues with CSST Gas Piping
Arcing damage impacts all metallic systems including wiring and all gas piping materials.
Damage not due to lightning induced voltage levels, but due to large differential in voltage potential.
Utility Issues with CSST Gas Piping
Model and State Code Conflicts
• National Fuel Gas Code
• International Fuel Gas Code
• National Electrical Code
• Different editions enforced
• 50 different State Building Codes
• Utility facility code - NFPA 54
Utility Issues with CSST Gas Piping
Manufacturer’s Design and Installation Guide
1. Used in conjunction with state
regulations, code and local practices
2. Defer to Design Guide if no
coverage in state or local regulations
3. If conflict exists, then more stringent
practice applies
4. Updated frequently
Utility Issues with CSST Gas Piping
NEC: Equipment Grounding Conductor
All gas piping electrically
continuous
EGC sized to protect against
ground faults
EGC sized based on branch circuit
12/14 AWG wire not designed to
handle lightning voltage
Utility Issues with CSST Gas Piping
2009 & 2012 IFGC/UPC/NFGC: Bonding
CSST gas piping systems shall be bonded to the electrical service
grounding electrode system. The bonding jumper shall connect to a
metallic pipe or fitting between the point of delivery and the first
downstream CSST fitting. The bonding jumper shall not be smaller
than 6 AWG copper wire or equivalent. Existing steel pipe or copper
tubing gas piping systems which are modified by adding one or
more segments of CSST of any length shall be bonded in
accordance with this section.
Utility Issues with CSST Gas Piping
Bonding Clamp Attachment
Never place bonding
clamp directly on
CSST.
Utility Issues with CSST Gas Piping
Bonding Requirements
Gas piping systems that
contain one or more segments
of CSST shall be bonded.
Utility Issues with CSST Gas Piping
Bonding Connections
Gas piping shall not be used as a grounding electrode
Utility Issues with CSST Gas Piping
Bonding Conductor Sizing
Conductor at least 6 AWG
copper or 4 AWG aluminum
Conductor single or multi-strand
Conductor length and gauge are
inter-related, but length is not
specified in the NEC
Utility Issues with CSST Gas Piping
No Separate Gas Grounding Electrode
Gas piping shall not be
used as a grounding
conductor or electrode.
Bonding clamp only on
customer’s side of the
meter.
Only one grounding
system for the house.
Utility Issues with CSST Gas Piping
Underground PE Piping
Copper tracer wire will be energized and arc to PE
Tracer wire can energize house piping when attached to riser
Increase and maintain minimum physical separation distance (6-in)
Utility Issues with CSST Gas Piping
Bonding Effectiveness Research
Impact on 2015 NFGC
• Bond is effective (no arcing damage to CSST)
• Indirect and partial direct lightning strikes
• Lightning energy 8/20 and 10/350 up to 10kA
• No damage for long conductors (up to 150-ft)
• No arcing for shorter conductors (< 75-ft)
• Lightning entry point varied
• Clamp location not significant factor
• Multiple bonding not justified for SF house
Utility Issues with CSST Gas Piping
2015 NFPA 54 Code Requirements
• Bonding is required for CSST
• Clamp located anywhere
• Single point of attachment
• Conductor of 75-ft or less
• Required for new and retrofit
• Bond all grounding electrodes
Utility Issues with CSST Gas Piping
ANSI LC-1-2014 CSST Standard
• New listing criteria for arc-resistant jacket
• Yellow and black jacket color
• Installer training program
29
Utility Issues with CSST Gas Piping
Arc-Resistant Jackets
• Conductive jacket
• Arc energy absorbed
• Listed to CSA LC-1 Standard
• Protection up to 5 Coulombs
• Approved as alternate method
30
WARDFLEX II
Utility Issues with CSST Gas Piping
Arc-resistant Protective Jacket is fully tested*
[* No product is immune from lightning damage.]
Utility Issues with CSST Gas Piping
www.CSSTSafety.com
Customer Awareness Programs
Questions and Answers?
Bob Torbin
Director of Codes and
Standards
(413) 388-2390