Metal gas piping: NEC Sec. 3.14(a) requires you to link the aboveground section of a metal gas piping system to a grounding electrode system for safety reasons. The use of aboveground sections of a metal gas pipe system or its components as a conductor in electrical circuits is prohibited by NFPA 54, Section 3.15. This means that you must connect one end of a wire to each end of the gas pipe if you want them to function as a single circuit (aka a "wire-to-wire connection"). Otherwise, if they are not connected, they may act as separate circuits and could have different voltage levels if one section gets hot while another one isn't touching any conductors.
All metal gas piping systems should be grounded to protect against electrocution. If you plan to drill into your foundation, connect the piping system to an existing ground rod or other continuous earth path. You can also connect multiple ground cables to the foundation if you want to ensure that someone will be able to reach all parts of the system later on.
If you don't have access to the basement wall, there are two options here. You can dig a hole around the pipeline and bury it completely, or you can wrap electrical tape around the outside of the pipe starting at both ends and wrapping once around each piece of pipe to create a closed loop. Make sure you follow the correct labeling guidelines when installing any type of underground electric service!
Yes, I mentioned metal gas pipe should be linked to the grounded conductor of the supply system. Metal gas pipe must be attached to the grounding electrode system, according to Section 250-104 (b). This can be accomplished by terminating at the neutral bar or any of the grounding electrode system's electrodes. If metal gas pipe is not connected to one of these locations, it cannot provide a complete circuit and will not be tied into the ground system.
The purpose of linking metal gas pipe to the ground system is two-fold: first, to prevent current from flowing through the gas pipe, which would cause corrosion; second, to ensure that anyone who might come in contact with the gas pipe gets some form of protection from being electrocuted. Corrosion could also occur if metal water pipes are not grounded, so make sure those are linked up as well.
Grounding is very important for equipment grounding sites, power lines, and anything else that may conduct electricity. It is also important to ground metal piping, because if it were not done properly, this type of wiring would create a path for current to flow through it, causing damage over time.
Some utilities will tap into existing house wiring to connect metal gas pipe to the ground system. However, this is not required by law in all areas. The best option is to have your local utility do this for you. It is their job after all!
According to NFPA 54 3.14 (a), any aboveground section of a gas pipe system upstream of the equipment shutdown valve must be electrically continuous and bonded to any grounding electrode. Section 250-104 of the National Electrical Code (NEC) backs up this obligation (b). The bonding connection should be made at the manufacturer's recommended location. If an underground gas main has been installed with its outer surface exposed, it should be bonded to some form of metallic material (such as an electrical panel) if possible. This can be done by using cable ties or wrapping wire around the pipe to create a conductive loop. If this area is not accessible, one option is to wrap the pipe with aluminum foil and tape it into place.
The purpose of this requirement is to provide an electrical path in case of damage to the gas piping. Any break in this section of pipe would prevent electricity from reaching the meter or other attached equipment, thereby preventing ignition of any gas that may have accumulated inside the pipe.
If the gas company has not put in an electric shutoff valve on the street side of the meter, then the bonding connection should be made at the meter base or pedestal. This prevents gas from escaping if someone cuts the pipe near the ground. They use a special tool for this job; it creates a spark to break any gas bubbles in the pipe. This tool is required by law in some cities.
Metallic pipe or tubing exposed to corrosive activity, such as soil conditions or moisture, must be well protected. Underground gas pipe should not be considered appropriate protection for zinc coatings (galvanizing). That much is obvious. The IRC prohibits galvanizing underground gas pipe. The only way to legally bury it is to coat the inside of the pipe with a noncorrosive material.
The only way to protect the zinc coating from corrosion is by covering it up. You can't just leave it exposed to the elements because that would cause the metal to oxidize and peel away from the pipe. Burying the pipe prevents this from happening.
If you want to bury your metallic gas pipe you will need to use stainless steel pipe. The outside of the pipe will need to be coated with zinc to prevent animals and insects from eating through it.
Stainless steel gas pipe can be buried up to six inches deep in stable soil. It is recommended that you have the pipe tested every time you add or remove an inch of water from the surrounding area. If any rust appears on the pipe, cover it with additional soil until it can be repaired or replaced.
Steel, copper, and brass: Black steel is the most often used gas pipe material. Some locations allow the use of galvanized steel, copper, brass, or CSST (Corrugated Stainless Steel Tubing), although some utilities explicitly ban the use of copper. Copper is widely used in different parts of the world. It's affordable and easy to work with, but it can be toxic if not handled properly. Brass has the same problems as copper and is no longer recommended by some manufacturers.
All types of pipe are capable of carrying gas, but only steel and cast iron have been used for actual gas service. Painted metal piping has been used for water services since before World War II, so it can also be found on houses built before then. But unless the house was actually located near a factory that used metal paint, it's very unlikely that you will find any today because they deteriorate quickly due to the humidity in homes. The same thing happens to copper piping - except that it will tarnish rather than peel like painted metal.
The main advantage of steel over other materials is its resistance to corrosion. When exposed to moisture, carbon dioxide from air pressure, and other chemicals, metals such as zinc and copper become acidic which can cause them to corrode. This is not a problem with steel because there is a protective oxide layer that forms naturally when it is exposed to oxygen in the air. Otherwise, it would burn easily.