Low-Frequency Electromagnetic Field Assessment

Comprehensive measurement of ELF magnetic and electric fields from power lines, wiring, and appliances, with comparison to building biology guidelines.

Book Assessment

Understanding Low-Frequency EMF

Low-frequency electromagnetic fields (ELF-EMF) are produced by anything carrying alternating current—power lines, building wiring, appliances, and electrical equipment. In Australia, the mains frequency is 50 Hz, and most domestic EMF exposure occurs at this frequency and its harmonics.

ELF magnetic fields penetrate most building materials and the human body freely. Research has linked elevated magnetic field exposure to increased childhood leukemia risk (classified as possibly carcinogenic by IARC), sleep disturbances, and other biological effects. Electric fields interact primarily with the body surface but can induce measurable body voltage.

Magnetic vs Electric Fields

Magnetic fields are generated by current flow and are difficult to shield. Electric fields are created by voltage and can be shielded by grounded conductive materials. A thorough assessment measures both field types, as they have different characteristics and mitigation approaches.

Common Sources

Power lines and substations
Electrical wiring in walls and floors
Appliances (refrigerators, HVAC, etc.)
Electric meter boxes
Solar inverters
Electric vehicle chargers
Transformers
Ground currents and stray voltage

What We Measure

Magnetic field strength (milliGauss/microTesla)
Electric field strength (V/m)
Body voltage testing
Dirty electricity (high-frequency voltage transients)
Ground current detection
24-hour logging where indicated
Source identification and tracing
Comparison to biological safety guidelines

Our Standards

We report findings against Building Biology guidelines (SBM-2015) rather than ICNIRP limits, which address only acute thermal effects and ignore the substantial body of research on non-thermal biological effects. Building Biology guidelines recommend sleeping area magnetic fields below 20 nT (0.2 mG) for no concern, with levels above 100 nT (1 mG) considered elevated.

Wiring Issues

Elevated magnetic fields often indicate wiring problems—neutral-ground bonds, shared neutrals, or improper grounding. These issues not only create EMF exposure but can represent fire hazards. We recommend electrician evaluation when wiring anomalies are detected.