Infrared saunas have become a popular choice for personal wellness, utilizing specialized heating panels that emit radiant heat to warm the body directly. This reliance on electrical components has led to increased consumer concern regarding electromagnetic fields, or EMF. In response, manufacturers began labeling products as “low EMF,” a term that is now a major factor in purchasing decisions. Understanding what this label truly signifies requires examining the scientific principles behind these invisible fields. This article defines EMF, explains how sauna design influences its levels, and provides steps for verifying “low EMF” claims.
Understanding Electromagnetic Fields (EMF)
Electromagnetic fields are areas of energy that surround any electrical device or wiring using power. These fields are categorized into two main components relevant to saunas: electric fields and magnetic fields. Electric fields are produced by voltage and exist even when a device is plugged in but not turned on. They are measured in volts per meter (V/m) and can be mitigated with proper grounding and conductive shielding materials.
Magnetic fields are generated only when current is flowing through the wires, meaning they are present when the sauna is turned on and heating. This component is the primary focus of “low EMF” claims and is measured in milligauss (mG). Unlike electric fields, magnetic fields are more challenging to block, requiring specific engineering techniques rather than simple shielding.
A third type of EMF, radiofrequency (RF) radiation, is associated with wireless devices like Wi-Fi or Bluetooth, which may be present in a sauna’s control panel. However, the magnetic and electric fields from the heating elements operate at Extremely Low Frequencies (ELF) and are the main concern when evaluating a sauna’s core design. The close proximity of a user to the heating elements makes the level of exposure a valid consideration.
How Sauna Design Impacts EMF Levels
The core of a sauna’s EMF output is found in its heating elements and the wiring that supplies them with power. The magnetic field component is created by the high electrical current needed to power large heating panels, such as those made from carbon or ceramic. Manufacturers reduce the magnetic field by employing engineering solutions designed to cancel the field at its source.
One common and highly effective technique is the use of twisted wiring within the heater panels and their power cords. By twisting the positive and negative electrical conductors closely together, the magnetic fields generated by the current flowing in opposite directions largely cancel each other out. This field cancellation is a specialized approach to reducing the magnetic field component, which is difficult to block with physical materials.
Electric fields are addressed through different design strategies, primarily involving grounding and shielding. Manufacturers use grounded metal shielding around the wiring and the back of the heating elements to capture and divert the electric field energy away from the user. Strategic placement of the power supply and control box, keeping them further away from the user’s seated position, helps ensure that the fields dissipate before reaching the body, as EMF strength drops dramatically with distance.
Defining and Verifying “Low EMF” Claims
The term “low EMF” is not standardized by a single global regulatory body, but industry claims typically reference established precautionary benchmarks. The most commonly cited threshold for magnetic fields is 3 milligauss (mG), a level historically suggested as a precautionary limit for continuous exposure. A sauna labeled “low EMF” generally aims to keep its magnetic field readings below this 3 mG level.
For consumers, the most critical factor in verifying a claim is the location where the measurement was taken. A reading taken directly on the heating panel surface will be higher than a reading taken at the user’s seated position, which is the only relevant measure of personal exposure. Reliable manufacturers provide documentation showing the magnetic field reading, ideally below 3 mG, taken at the head and torso positions on the sauna bench.
Beyond the magnetic field, a comprehensive “low EMF” claim should also address electric field exposure. This is quantified by measuring the user’s body voltage while inside the sauna, expressed in millivolts (mV). A grounded system will dramatically reduce this body voltage, showing the electric field has been properly managed. Consumers should look for documentation of independent, third-party testing that specifies all three factors—magnetic field (mG), electric field (V/m), and body voltage (mV)—to ensure the product meets a verifiable standard.