Utility Issues with CSST Gas Piping

Utility Issues with CSST Gas Piping

October 2014


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


Standard Yellow Arc-Resistant Black

Lightning protection system

Bonding of piping to grounding electrode system

Arc resistant protective jacket


Protection from Lightning


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


Lightning Pathways


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


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


Lightning does not discriminate. It seeks all pathways to ground.

It will damage all mechanical/electrical systems.


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.


Underground PE Piping Fires


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


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


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


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.


Bonding Clamp* Attachment

* Bonding Clamps listed to UL 467


Bonding Clamp* Attachment

* Clamp listed to UL 467 for CSST


Bonding Clamp Attachment

Never place bonding

clamp directly on

CSST.


Bonding Requirements

Gas piping systems that

contain one or more segments

of CSST shall be bonded.


Bonding Connections

Gas piping shall not be used as a grounding electrode


Bond Connection to Grounding System


Bond to Intersystem Termination or Panel Box


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


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.


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)


Daisy Chaining of Meters


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


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


ANSI LC-1-2014 CSST Standard

• New listing criteria for arc-resistant jacket

• Yellow and black jacket color

• Installer training program

29


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


Arc-resistant Protective Jacket is fully tested*

[* No product is immune from lightning damage.]


What About Legacy Homes?


Who is On-Board?

AMERICAN PUBLIC GAS ASSOCIATION


www.CSSTSafety.com

Customer Awareness Programs

http://www.csst.com/

Questions and Answers?

Bob Torbin

Director of Codes and

Standards

[email protected]

(413) 388-2390

mailto:[email protected]

Utility Issues with CSST Gas Piping

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