Reference · Glossary
Recovery gear glossary: the words the marketing leans on, in plain English
Every recovery category has a handful of terms the marketing leans on, and most of them sound more settled than they are. This page tells you what each one actually means before you spend. You will see the same words across red light panels, infrared saunas, PEMF devices, and cold plunges, and they fall into two camps: specs you can check and distinctions that decide whether a claim holds up.
The useful habit is simple. When a brand quotes you a number, the term attached to it tells you whether anyone can verify it. That is what these definitions are for. Skim the group you are shopping, or read straight through.
Cross-category
Terms that apply to every rubric.
- Composite score
- Our 0 to 10 opinion of a device under a versioned, category-specific rubric, computed by a deterministic engine from measured specs. It is our judgment under a published method, not an objective fact or medical advice.
- Band (Excellent / Strong / Mixed / Limited)
- The label attached to a composite score: Excellent at 8.5 and above, Strong at 7.5, Mixed at 6.5, Limited below 6.5. A Limited score is often a flag that a key claim is unverified, not a verdict that a device is bad.
- Confidence (Partial / Verified)
- How solid the underlying data is. Partial means web-sourced and not yet independently re-measured; Verified means the price, spec, and regulatory facts were confirmed against a primary source such as a manufacturer page, an independent tester, or the openFDA database.
- Measured vs claimed
- A brand's advertised number shown against an independent measurement, with a live, dated source link. The gap between the two is the story we score. See the measured vs claimed report.
- FDA registered / listed
- Paperwork: an establishment registration or a device listing. It is not a clearance or an approval, though it is frequently marketed as if it were one.
- 510(k) cleared
- A real FDA clearance, meaning the FDA agreed a device is substantially equivalent to an existing one for a stated use. It is rare in this gear and we verify it against the openFDA 510(k) database, never from marketing wording. It is a regulatory step, not a promise of a result.
- Source-or-pull rule
- Our editorial rule that any measured brand figure must carry a live source link and date or be pulled. If we have no independent measurement, we say so rather than asserting that a device underperforms.
Red light
The panel specs, led by irradiance at a usable distance.
- Irradiance (mW/cm²)
- The power density of light hitting a surface, the headline red light spec. It is only meaningful with a stated distance, because it falls off sharply as you move away from the panel.
- Effective irradiance
- The only irradiance we credit: a figure independently measured at 6 inches, or a manufacturer number explicitly stated at 6 inches or more. A number with no stated distance, or one read at the panel surface, returns nothing and is capped and flagged. See why distance is the whole game.
- Surface reading
- An irradiance figure measured at the panel face (0 inches), where it is highest and not usable for treatment. We do not credit it.
- Wavelength (nm)
- The color of the light in nanometers. The studied bands are visible red around 660 nm and near-infrared around 850 nm; some panels add 480, 630, 810, 830, or 1060 nm. See wavelengths explained.
- EMF (panel)
- Electromagnetic field from a panel's driver and electronics. It falls off with distance, so the honest way to state it is low EMF at a normal treatment distance. See EMF and flicker.
- Flicker / flicker-free
- Ripple in an LED driver's output. A flicker-free or low-modulation driver is preferable; the honest disclosure is a percent-modulation figure, not a marketing word.
- Cost per treatment area
- Our value metric: price divided by emitting area in square centimeters, scored against the format-class median. It lets a large full-body panel and a small targeted one be compared fairly.
Infrared sauna
EMF verified at the seat and an honest spectrum claim.
- EMF at the seat (verified EMF, mG)
- The only sauna EMF figure we credit: milligauss measured at the seated body position by a named third party. A number read at the heater or floor, a brand-stated figure with no report, or a bare low-EMF label earns nothing. See why the number means nothing without a position.
- Far infrared / near infrared
- Far infrared warms you with longer wavelengths from carbon or ceramic panels; near infrared is a shorter wavelength, usually from LEDs or incandescent bulbs. Most cabins are far-infrared.
- Full spectrum
- A claim to deliver near, mid, and far infrared. We treat it as honest only when there is a separate near-infrared emitter (named LED wavelengths or incandescent lamps), not a relabeled far-infrared panel. See what full spectrum should mean.
- NIR emitter
- A distinct near-infrared source: a dedicated LED array with named wavelengths, or incandescent lamps hot enough to emit near-infrared. Its presence is the test of a real full-spectrum claim.
- ETL / UL listing
- An electrical-safety listing from a testing lab (Intertek's ETL or UL). It is a safety mark, not an FDA clearance, and it is what our Safety dimension looks for alongside a clean recall record.
PEMF
A field strength you can read at a stated frequency.
- Verified field spec
- The only PEMF field figure we credit: a magnetic flux density in real units (normalized to microtesla) published with a stated frequency in Hz. A unit-less level, a bare peak, or a surface-only figure is capped. See why up to X gauss is not a spec.
- Microtesla / gauss
- Units of magnetic flux density (1 gauss is 100 microtesla). A real field spec is stated in these units; we normalize to microtesla to compare devices.
- Peak gauss
- A momentary pulse maximum, often marketed as up to X gauss. It is not a sustained field at a stated frequency, so we do not treat it as a usable spec on its own.
- Frequency (Hz) and waveform
- The pulse rate in hertz and the shape of the pulse (sine, square, trapezoidal). A published frequency range and a named waveform are signs of disclosure; we credit a field figure only when a frequency is stated.
Cold plunge
A real chiller, the running cost, and water care.
- Built-in chiller vs ice-only
- The line that splits the category: a chiller holds a set temperature without ice; an insulated tub you fill with ice does not. We score the two as different products. See what a chiller actually buys you.
- Running cost
- The chiller's estimated annual electricity, the cost most brands leave off the box. It varies with chiller power, insulation, climate, and rates. See running costs.
- Water care (ozone / UV / filtration)
- Systems that let you reuse the same water: ozone and UV sanitize, filtration removes debris. They matter because a plunge holds standing water you sit in repeatedly.
For the full scoring method, see the methodology. Browse the guides for a deeper explainer on any term above.