CSST Gas Piping: What It Is, How It Works, and Why Proper Training Matters

What Is CSST?

CSST stands for Corrugated Stainless Steel Tubing. It is a flexible gas piping material used to distribute natural gas or propane inside residential, commercial, and industrial buildings.

Unlike traditional rigid black iron pipe, CSST is made from thin-wall stainless steel formed into a corrugated, flexible tube. That flexibility allows installers to route gas piping around framing, through walls, between floors, and to appliances with fewer fittings and fewer directional changes.

CSST has become popular because it can reduce installation time and may reduce the number of joints in a gas piping system. The International Code Council notes that contractors adopted CSST quickly because it can be installed faster and with fewer fittings compared with traditional pipe.

For companies like Enolgas USA, which serves HVAC, plumbing, industrial, and gas

applications, CSST fits into the broader conversation around safe, efficient gas system design.

Enolgas USA’s product line includes gas and water ball valves, fittings, actuators, metering

systems, and related flow-control solutions designed for durability, safety, and compliance.

How CSST Works

CSST works as a flexible fuel gas distribution line. Once installed, it carries natural gas or

propane from the gas supply source to appliances such as:

• Furnaces

• Boilers

• Water heaters

• Ranges and cooktops

• Fireplaces

• Dryers

• Outdoor gas appliances, where allowed by code and manufacturer instructions

The corrugated design gives the tubing its flexibility. This allows the tubing to bend around

obstacles and travel through building cavities more easily than rigid pipe.

A complete CSST system typically includes:

• CSST tubing

• Manufacturer-approved fittings

• Manifolds, where applicable

• Gas shutoff valves

• Striker plates or protective devices

• Bonding/grounding components, where required

• Appliance connections and termination fittings

The current CSA/ANSI LC 1:23 / CSA 6.26:23 standard covers fuel gas piping systems using CSST and includes tubing, fittings, striker plates, manifolds, regulators, manual gas valves, quick-disconnect devices, excess-flow valves, and gas convenience outlets within its scope.

What Is CSST Used For?

CSST is used primarily for fuel gas piping systems inside buildings. It is common in both new construction and remodeling projects because it gives installers more routing flexibility than rigid piping.

Typical applications include:

Residential gas systems

CSST is often used to supply gas to furnaces, water heaters, ranges, fireplaces, clothes dryers, and outdoor cooking areas.

Commercial buildings

Restaurants, multifamily buildings, offices, and light commercial facilities may use CSST where flexible routing and efficient installation are beneficial.

Retrofit and remodeling projects

Because CSST is flexible, it can be especially useful when adding a new gas appliance to an existing building.

Gas distribution with manifolds

Some systems use a manifold approach, where gas is distributed from a central point to multiple appliances.

It is important to note that CSST is not a universal substitute for every type of gas piping.

Installations must follow the manufacturer’s design and installation guide, local codes, utility

requirements, and the authority having jurisdiction.

Why CSST Requires Special Attention

CSST is flexible and efficient, but it must be installed correctly. Gas piping is a safety-critical

system, and improper installation can create serious risks, including gas leaks, fire, explosion, or damage from electrical energy.

One of the most important safety topics with CSST is bonding.

What Is CSST Bonding?

Bonding connects the metallic gas piping system to the building’s electrical grounding electrode system. The purpose is to help reduce voltage differences between conductive systems, especially during electrical events such as nearby lightning strikes.

The ICC explains that non-arc-resistant yellow CSST requires permanent bonding to the

structure’s grounding electrode system to help lower voltage build-up caused by outside

electrical sources such as lightning.

Model codes recognize two main protection approaches:

1. Additional bonding connection for certain CSST systems

2. Listed arc-resistant jacketed CSST, installed according to the applicable standard and

manufacturer instructions

Because requirements can vary by product type, jurisdiction, and adopted code edition, installers should always verify the applicable local code and manufacturer instructions before installation.

Training and Installer Requirements

CSST should only be installed by qualified professionals.

Many CSST manufacturers require installers to complete product-specific training before

installing their systems. For example, Gastite states that its flexible gas piping systems must be installed by a qualified installer who has successfully completed its in-person or online training program and meets state or local requirements.

In practice, this usually means the installer should:

• Be licensed or otherwise qualified under local rules

• Complete the CSST manufacturer’s training program

• Follow the manufacturer’s design and installation manual

• Use only approved tubing, fittings, and accessories for that system

• Understand gas pipe sizing, routing, protection, pressure testing, and bonding

• Coordinate inspections with the local authority having jurisdiction

This training matters because CSST systems are manufacturer-specific. Tubing and fittings from different brands are generally not interchangeable unless explicitly approved by the

manufacturer. Using the wrong fittings or skipping required steps can compromise the system.

Code and Compliance Considerations

CSST installations are governed by a combination of:

• Manufacturer installation instructions

• Local building, plumbing, mechanical, fuel gas, and electrical codes

• National model codes, where adopted

• Inspection requirements from the authority having jurisdiction

• Utility or propane supplier requirements

The CSA/ANSI LC 1:23 / CSA 6.26:23 standard is the current listed standard for fuel gas piping systems using CSST, published in 2023.

Because code adoption varies by state, county, and municipality, the safest approach is simple: always check the local code, the manufacturer’s installation guide, and the project

inspector’s requirements before beginning work.

Best Practices for Safe CSST Installations

A safe CSST installation starts before the tubing is ever uncoiled. Contractors and designers should consider:

Proper system design

Gas load, appliance demand, pipe length, pressure, and allowable pressure drop must all be calculated correctly.

Approved components

Use the tubing, fittings, valves, manifolds, and accessories approved for the system.

Physical protection

Where CSST passes through framing or areas vulnerable to screws, nails, or abrasion, proper protection devices such as striker plates may be required.

Bonding and electrical protection

Follow manufacturer instructions and local code requirements for bonding, grounding, and arc resistant jacketed products.

Inspection and testing

Gas piping systems should be pressure-tested and inspected before being placed into service.

Ongoing professional support

Suppliers and manufacturers play an important role by providing technical documentation,

certified components, and product support. Enolgas USA highlights product development,

certifications, manufacturing, logistics, and ongoing support as part of its business approach.

Where Enolgas, USA Fits In

Gas piping systems depend on more than tubing alone. A complete system requires reliable valves, fittings, controls, and supporting components that help manage gas flow safely and efficiently.

Enolgas USA currently supports the HVAC, plumbing, industrial, and gas markets with a range of products, including gas and water ball valves, fittings, actuators, metering systems, and other flow-control solutions. Building on that foundation, Enolgas USA is also developing a complete gas system offering, which is expected to include CSST as part of a broader, integrated solution.

This upcoming total gas system reflects the growing demand for streamlined, compatible, and code-conscious gas installation products. By bringing together CSST, valves, fittings, and related components under one system approach, Enolgas USA aims to help contractors, distributors, engineers, and designers work with products that are built to function together.

As the gas industry continues to prioritize safety, efficiency, and compliance, integrated system solutions can make it easier for professionals to design and install reliable gas distribution systems from source to appliance.