Static Dissipation vs. Conductivity: Why It Matters for Hose Selection
Selecting the right hose for your fluid system involves more than matching pressure and temperature requirements. Two critical characteristics that can significantly impact system safety and performance are static dissipation and conductivity. While these terms are often used interchangeably, they serve different purposes and understanding the distinction is essential when choosing hose materials for your application.
Static dissipation refers to a material's ability to safely discharge static buildup that can be generated by fluids such as steam, hydraulic oil, dielectric fluids, and high-velocity gases flowing through a hose. Conductivity, on the other hand, is the ability of a material to transmit electrical current from one point to another. Depending on the application, a hose may need to be conductive, non-conductive, static dissipative, or a combination of these characteristics. In this video, learn how these properties affect hose selection and discover how the right hose can help reduce safety risks, improve reliability, and support optimal fluid system performance.
Video Transcript
When determining the right hose for your application, there are various characteristics to consider. Two of the most important are static dissipation and conductivity. Understanding these important factors can help you avoid potentially dangerous safety issues within your system.
Static dissipation is the ability of a material to safely discharge static buildup. This is important because static electricity can be generated by certain fluids when passing through the hose. A common definition of a material that is static dissipative is one that has an electrical resistance more than one times ten to the fourth ohms, but less than one times ten to the eleventh ohms.
Some examples of fluids that have the potential to generate static charge within the hose core are steam, dielectric fluids, high-velocity gases, and hydraulic oil. These applications require a hose core that can effectively dissipate static buildup. Materials that are not dissipative, including most soft-core materials such as PFA and PTFE, will allow the static charge to build up within the hose.
This kind of buildup can cause a tiny hole in the hose to develop, resulting in a hard-to-detect system fluid leak and providing a path for any pent-up static electricity to jump to the closest conductive material. Any size hole creates a hazard in environments using toxic or combustible gases or liquids.
Conductivity, meanwhile, is the ability of a material to transmit or conduct an electrical charge. A conductive material has an electrical resistance less than one times ten to the fourth ohms. Typically, conductive hoses are made of all-metal materials. Certain applications may require a hose to be either conductive or non-conductive. For example, most semiconductor processes would use a non-conductive hose, while a general industrial setting would use a conductive hose.
A conductive hose allows for electrical charge to flow from one end connection of the hose to the other, independent of the core’s ability to conduct static charge. This can occur from one end connection to a metal braid or to the other end connection. In a static dissipative hose, it is the hose’s core material that can dissipate small static charges to an area outside the hose. Typically, this is done by allowing the small charges to flow to the braid material and then to an end connection.
However, it’s critical to remember that static dissipation and conductivity are two completely distinct characteristics of a hose. A conductive hose does not mean that the hose is static dissipative, and a static dissipative hose is not necessarily conductive.
For example, an application may require a hose that is functionally non-conductive but could generate static. An effective way to enable soft-core hoses to dissipate static is to infuse them with a carbon material. The addition of carbon allows a minuscule flow of current that helps dissipate any static buildup. This type of construction allows the hose to remain functionally non-conductive while simultaneously enabling static dissipation.
Your ability to match the right combination of hose materials to the needs of your application can result in safer, more efficient fluid system performance. If you are interested in learning more about how to optimize hose selection in your facility, our Swagelok Hose Essentials training is a good starting point.
Our hose advisory services team can also work with you to provide guidance on hose selection, installation, inspection, and maintenance procedures to improve hose life and performance.
For more information about Swagelok hose advisory services, contact your local authorized Swagelok Sales and Service Center today.
