Designing HVAC for a SCIF is not the same as ordinary commercial HVAC work. These projects often require SCIF HVAC components that address metallic penetrations through the secure boundary. Every metallic line that crosses the secure wall, including a refrigerant line, can create a conductive path through the protected boundary.
Under ICD 705 related construction guidance, the treatment of these penetrations is reviewed as part of the facility security process. For metallic refrigerant lines, the decision often comes down to two possible approaches: grounding the line or installing a dielectric break.
The question engineers, contractors, and security officers often face is simple: for SCIF refrigerant lines, when is grounding enough, and when is electrical isolation required?
How a Metallic Refrigerant Line is Treated
There is no single rule that applies to every SCIF project. The required treatment is determined by the TEMPEST authority, the CTTA, based on the facility design, the secure boundary, and the project’s security requirements.
Grounding keeps the refrigerant line as one continuous metal path, but bonds it to building ground. A dielectric break physically interrupts that conductive path by placing a non-conductive section in the line.
Where the CTTA calls for electrical isolation rather than grounding, a dielectric break is the method used to interrupt the conductive path.
Grounding vs. a Dielectric Break
| Grounding | Dielectric Break | |
| How it works | Bonds the line to building ground so unwanted current or signal can attenuate | Inserts an insulating section into the line |
| The line itself | Remains one continuous piece of metal | Is split by a non-conductive section |
| What it does to the path | Simply bonds the metallic pipe to building ground | Removes the continuous conductive path |
| Best use | When bonding is accepted by the project authority | When electrical isolation is required |
The difference is important. Grounding depends on the quality and continuity of the ground connection. A dielectric break removes the metal path itself. That is why it is used when the requirement is true electrical isolation of the refrigerant line.
Why a Refrigerant Line is the Hard Case
Some metallic penetrations are easier to isolate. A non-metallic section can often be added to certain ducts, drains, or water piping systems that operate at low pressures.
A refrigerant line is different. It is part of a sealed, high-pressure copper circuit. A standard plumbing dielectric union is not designed for refrigerant pressures, refrigerant oil exposure, or HVAC installation conditions. At the same time, refrigerant cannot simply be routed through a basic plastic section.
That is what makes refrigerant lines one of the more difficult SCIF HVAC penetrations to isolate. The component has to interrupt the electrical path while still being suitable for the refrigerant system.
What is the Right Choice for Your Project?
The decision starts with the TEMPEST review. If grounding is accepted, the line can be bonded according to the project requirements. If electrical isolation is required, the next step is to confirm that the dielectric break is designed for refrigerant service.
For refrigerant lines, the key details are:
| Checkpoint | Why it matters |
| Line size | The break must match the copper refrigerant line size |
| Pressure rating | The component must be suitable for the system pressure |
| Refrigerant compatibility | Materials must suit refrigerant and oil exposure |
| Installation method | The break must be installed without damaging the assembly |
| Project requirement | The final treatment should match the CTTA review |
Once the review calls for isolation, the issue is no longer just grounding versus a break. The practical question becomes whether the selected break is actually built for a refrigerant line.
A Purpose-Built Dielectric Break for SCIF Refrigerant Lines – EKFox Gear
EKFox Gear manufactures a patented non-conductive refrigerant line break designed for this specific requirement. It provides electrical isolation for metallic refrigerant lines that pass through security partitions or secure walls, while still being built for refrigerant service.
The product is available in eight sizes to match standard split-system lines. When a TEMPEST review calls for electrical isolation of the refrigerant line, it gives engineers and contractors a purpose-built option instead of trying to adapt a plumbing component to an HVAC application.
View the full size range and pressure ratings on the product page, or contact EKFox Gear for pricing and lead times for your project.
