EMP shielding

EMP shielding protects critical electronics from electromagnetic pulses. A shielded room with filtered power and signal entries keeps essential systems working through pulse events. This page is for consultants and estates teams responsible for critical infrastructure.

• EMP protectionShielding for critical electronics
• Filtered power entriesPower lines sealed against pulses
• Shielded doors and ventsEvery penetration treated
• Installed and testedPerformance verified on completion

What is EMP shielding

An electromagnetic pulse is a short, intense burst of electromagnetic energy that can damage or upset unprotected electronics. EMP shielding is the set of measures that keeps such a pulse away from critical equipment: a continuous shielded envelope around the room, with every power and signal entry filtered. It is one discipline within our shielding range, aimed at sites where equipment failure is not an option.

Protection is specified as attenuation: how much of the pulse the room blocks across the frequencies of concern. The design starts from the equipment to be protected and the level of assurance the site needs, agreed with the consultant before any construction begins.

Which EMP specification do you need

An EMP shielded room is a system, not a single product. The table below lists the elements every design must include; leave one out and the pulse will find it.

How EMP shielding works

The room is lined to form a continuous conductive envelope: walls, floor and ceiling joined with sealed seams so the pulse cannot pass through. All services enter at defined points, and every power and signal line passes through a filter that blocks the pulse while letting the normal supply through.

Doors use conductive gaskets so the envelope stays continuous when they close, and ventilation uses waveguide vents that pass air but not signals. The layout keeps cable runs short and avoids new penetrations after the room is commissioned.

Cable routing inside the room is kept short and tidy, with services entering at one defined point so the envelope has a single boundary to defend. Filters are mounted where they can be reached for inspection, and spare ways are capped rather than left open. The layout is documented so future changes do not punch unplanned holes in the shield.

One unfiltered cable defeats the room. A pulse will enter through the weakest path. Route every power and signal line through filters at a single entry point, with no exceptions.

Combining EMP shielding with other ratings

Sites that fear EMP often face other threats too. Where blast is also a concern, blast resistant doors protect the room’s entrances, and attack, blast and gas protection adds gas-tight sealing and blast valves. The building line around the facility can use security doors rated to LPS 1175 against forced entry. Our standards hub explains the rating systems behind these products.

Where EMP shielding is used

Utilities and energy sites protect control rooms and switching equipment. Government and defence estates shield communications and command facilities. Data centres use shielded rooms for equipment that must survive pulse events and keep services running.

What affects the cost and lead time of emp shielding

Room size sets the lining scope, and the number of penetrations sets the filter count: each power and signal entry needs its own filtered treatment. New build rooms are simpler than retrofits, where existing services must be rerouted or sealed. The target attenuation and the extent of testing and documentation also affect the programme. No prices are given here because every room differs.

How to specify EMP shielding

1. List the equipment. Define what must keep working through a pulse event.
2. Survey the room. Record construction, services and every penetration.
3. Design the envelope. Fix the lining, entries, doors and ventilation.
4. Install shielding and filters. Build the envelope and fit filtered entries.
5. Treat every penetration. Seal doors, vents, pipes and cables.
6. Check the shielding. Confirm attenuation with independent testing.

EMP shielding FAQs