Bond, Pipe Bond

When Ian Fleming named his famous MI6 agent, he wanted the name to be as mundane and forgettable as possible. James Bond’s namesake was an American ornithologist, a book of whose Fleming happened to have at the house in the Caribbean where he wrote. In his own words, Fleming wanted, “Bond to be an extremely dull, uninteresting man to whom things happened”. As we all know, his character came to life, first literarily and then cinematically, in a very different way, and the original anonymity of the name became nothing more than an ironic footnote. The name and its stylized verbalization have become a sub-narrative unto themselves. People the world over know that you can invoke all sorts of things by announcing a last name and then restating it with the first and the last together: Bond, James Bond.

Much like Fleming’s original intention for the name of his secret agent, nothing about bonding gas lines is going to, at first, strike anyone as interesting. Let’s be honest, most people aren’t even completely sure where all the gas lines in their house are!

Legislative Action:

Why then did the 2017 session of the Virginia Assembly take interest in gas pipe bonding?

The short answer is that they did so to address safety issues arising from the use of CSST – Corrugated Stainless Steel Tubing. CSST is a material that was developed in Japan in the 1980s and was introduced into US markets in the early 90s. Compared with conventional black iron piping, CSST poses several advantages: it can be bent, it is light weight, fewer unions are needed, and it is cheaper. For builders, using CSST is a no-brainer. These benefits, however, only cover one side of the ledger. Since it is made of much thinner material, CSST is more prone to damage than black iron. When it gets charged with electrical current – say from damage to the electrical system or a lighting strike in the area – CSST can rupture. In a flash (forgive me), gas and electricity can be put into direct contract with devastating results. The internet, if you’re curious, is rife with stories about CSST explosions.


Because of the specter that CSST poses, the Virginia Assembly passed legislation which says that the following language must be included in home inspection reports for houses built before 2008 that have CSST:

“Manufacturers believe that this product is safer if properly bonded as required by the manufacturer’s installation instructions. Proper bonding of the product should be determined by a contractor licensed to perform the work in the Commonwealth of Virginia.”

For inquiring minds, 2008 was the year that it was first required that CSST installations in the Commonwealth be bonded in new construction. (Yes, I have seen unbonded CSST installations in houses built after 2008.)

To understand the steps that are being taken to minimize the danger CSST poses, we need to cobble together an idea of what bonding is.[1]


Bonding works on similar principles, but is not quite the same, as grounding. Strictly speaking, bonding is the process of connecting metal materials to lower the potential (voltage they can carry) between them. The difference in potential is what causes electrical shock or damage.

Mark C. Ode, writing for Electrical Contractor magazine, puts it this way: “The main purpose of this bond is to ensure that the metal water pipe is at the same zero voltage to ground as the service grounded conductor. A secondary purpose is to ensure that there is a path back to the service for electrical current flow if the metal water pipe becomes energized.”[2]

This is not a technical definition, but you could say that bonding is the process of leveling the electrical playing field.

Metal pipes of any application, that do not go to ground themselves, are bonded so that should they pick up current, electricity won’t suddenly enter an isolated system. Current running through unbonded or ungrounded metal poses substantial danger…as we all learned in elementary school. Bonding is usually achieved by securely attaching a wire to the piping on one end and the grounding bus in the electrical panel on the other. When it comes to gas piping specifically, the wire-to-pipe connection is usually on the house side of the meter, itself an exterior, grounded component.

If we pan back a little, dramatic shifts in our understanding of certain building materials are not unknown. Once upon a time, lead was used for piping and asbestos for insulation. More recently, polybutylene water piping was touted for its flexibility and easy price tag; then we found out that it is prone to leakage. Periodically the building industry moves away from or modifies materials based on their performance in the field. Plumbers don’t use polybutylene anymore, but do use cross-linked polyethylene (PEX) which has many of the same physical properties. Likewise, it has been reported that new CSST-like gas piping is coming out that is slightly less flexible but is heavier gauge and has a thicker jacket on the outside – AND gas piping is now routinely bonded.

Bonding all gas piping:

In the course of my work, I recommend bonding for every house with gas or propane service even if it has black iron or copper piping.


It makes the house safer, that’s why. Yes, black iron is less prone the rupture, but it isn’t perfect either.

It’s not unreasonable to make a comparison to smoke detectors. The classic 9-volt powered smoke detector didn’t really take off until the late 60s – early 70s, but millions of older homes across the country have been retrofitted with them. In Virginia, new homes are required to have smoke detectors installed in them at the time of construction, but hypothetically you can buy an old home without smoke detectors and leave it that way. This would, of course, be a terrible idea. Still, no law requires the installation of smoke detectors in a home that never had them.

So too, bonding gas lines adds a level of safety that, from the perspective of someone who looks at houses every day, is worth it.

Ian Fleming’s character, as it turns out, is dramatically different than the one he originally intended. Sure, amazing things happen to James Bond, but the character we know now is just as extraordinary as his adventures. CSST too was intended, as many building materials are, to be forgettable. And while certainly not entertaining, what it has undergone in the field has changed how we understand and treat it.

[1] Drinking martinis is not, in term of electrical safety, not a legitimate form of bonding.

[2] Ode, Mark C. “Bonding Water Piping.” Contractor: Power and Integrated Building Systems, July 2002, Accessed 5 Aug. 2017.