A Room That Is Silent Across Ten Billion to One.

Every electronic product has to answer two questions before it ships, flies, sails or drives: does it pollute the radio spectrum, and can it survive the pollution of others? Those are emissions and immunity, and the answers are only worth anything if they were measured in a room built to make the measurement true. Neometrix's EMI/EMC test laboratories are shielded anechoic chambers engineered to do exactly that — ≥100 dB of shielding so the outside world disappears, absorber linings until the room measures like open country (normalised site attenuation within ±4 dB), and test suites running from CISPR through MIL-STD-461, sized from bench equipment up to complete vehicles on an in-floor dynamometer.

The Laboratory Must Do Two Contradictory Things at Once

It has to be a Faraday cage — ≥100 dB of shielding, a factor of ten billion in power — so a city's radio chatter can't reach the receiver inside, and the lab's own kilowatt-class test fields can't reach the city outside. And it simultaneously has to measure like open country: a bare metal room is a hall of mirrors for radio waves, where every measurement would arrive twice, reflected. That tension never fully resolves; it's engineered around, continuously.

Lined Until It Measures Like Open Country

The shield is lined with ferrite tile for the low bands and hybrid pyramidal absorbers above them, until the room's normalised site attenuation tracks an ideal open-area test site within ±4 dB, point by point, frequency by frequency. Getting a shielded metal box to behave, electromagnetically, like an empty field is the core achievement of the absorber design.

Every Penetration Is a Potential Weak Point

Air enters through honeycomb waveguide vents that pass air through but cut off RF below their design frequency. Power enters through filtered feedthroughs. Doors seal on knife-edge contacts through beryllium-copper finger stock. The shield is only ever as good as its worst penetration — which is why every single crossing of the boundary is deliberately engineered, not treated as a minor mechanical detail.

The Room Itself Is the First Test Article

Before any product is ever measured inside it, the chamber itself is validated: shielding effectiveness to EN 50147-1/IEEE 299, normalised site attenuation to ANSI C63.4, site VSWR to CISPR 16-1-4, and field uniformity to IEC 61000-4-3, with 17025-traceable calibration carried in the scope of supply. A lab that hasn't proven itself first has no business proving anything about a customer's product.

One Discipline, Five Facility Types

The same underlying physics scales across five configurations: a 3-metre chamber for bench-scale products, a 10-metre chamber for machines, a MIL-STD-461-compliant room for defence electronics, an automotive hall with a turntable and an in-floor chassis dynamometer, and a fully anechoic RF chamber quiet to 40 GHz. What changes across all five is scale and configuration, not the underlying engineering discipline.

Where EMC Labs Actually Fail

Rarely in the steel itself. They fail at the door whose finger stock has fatigued after ten thousand closures, at a penetration someone added for one more cable and never filtered, and at ageing absorbers whose loss has quietly drifted until the normalised site attenuation walks out of tolerance — while the lab keeps issuing reports it can no longer actually stand behind. That's why the room is treated as the first test article, validated at handover and re-validatable after every change.

Frequently Asked Questions

Why does an EMI/EMC chamber need to both block outside signals AND avoid reflecting waves internally?
Because those are two separate, competing requirements that both have to be true at once. Blocking outside signals — the shielding — needs a continuous conductive metal boundary, essentially a sealed metal box. But a bare metal room reflects radio waves internally like a hall of mirrors, so any measurement taken inside would pick up both the direct signal and multiple reflected copies of it, making the measurement meaningless. The absorber lining (ferrite tile and pyramidal foam) solves the second problem by absorbing those reflections, while the metal shield behind it solves the first. Both layers are necessary; neither alone is sufficient.

Why is the chamber itself tested before any customer products go into it?
Because a chamber's entire value proposition is that a measurement taken inside it reflects the product's true behaviour, not an artifact of the room. If the shielding has degraded, or the absorber performance has drifted, or a door seal has fatigued, the chamber will produce measurements that look valid but aren't — and there's no way to tell from a single test result alone. That's why shielding effectiveness, normalised site attenuation, site VSWR and field uniformity are all independently verified against reference standards before the chamber is trusted with real product testing, and why that verification is repeated after any change to the facility.