Down to Earth EMF Services

EMF Surveys that don't cost the earth

EMF Surveys that don't cost the earth

EMF Surveys that don't cost the earthEMF Surveys that don't cost the earthEMF Surveys that don't cost the earth



The PF5 is an easy to use, pocket sized, accurate, power-frequency meter designed by EMFields using 25 years experience of EMF measurements and research.

The PF5 measures electric and magnetic EMFs in the ELF (Extremely Low Frequency) and VLF (Very Low Frequency) range. These EMFs are generated by house wiring, as well as various household appliances and electrical devices such as solar-panel inverters, laptop computers, induction cooking hobs, energy-saving compact fluorescent (CFL) lamps and some LED lights. The PF5 is able to measure the higher frequency electric and magnetic fields emitted by these appliances and devices.

Since the PF5 also measures frequencies in the VLF range, this sets it apart from most power-frequency meters on the market. Although some specialist meters also measure VLF frequencies, they tend to be expensive. The PF5, which has a frequency range of 20 Hz to well over 50 kHz makes it easy to measure these new major sources of EMF exposure.

Induction hobs use VLF magnetic fields to induce high currents in iron and steel pans which then internally heat the metal. They are very energy-efficient, but some of the VLF fields leak out around the base of the pan and expose the person doing the cooking. A 2012 study that measured 16 induction hob units found that most could exceed even the very high ICNIRP levels. Induction hobs can expose you to some of the highest exposures that most people will experience in their lives.

These are amongst the most concerning new sources of our electromagnetic field exposures as the currents they induce in your body are proportional to the frequency. So a magnetic field at 25000 Hz (25 kHz) will induce 500 times more current in your body compared with same strength of field at 50 Hz.

Most non-sine-wave solar power inverters generate high levels of VLF electric and magnetic fields that the PF5 can also measure while most power-frequency EMF meters will ignore them.

Note that a 0.4 µT (4 mG) magnetic field at 25 kHz will induce the same currents in your body tissues as a 200 µT (2000 mG) magnetic field at 50 Hz, so it is advisable to limit your exposure to these VLF fields.

The PF5 is easy to use. Press the button once to activate the meter. It will measure the magnetic fields and the right-hand scale is indicated by a green LED. Press the button again to change to measuring electric fields. Each short press will cause it to swap between electrical and magnetic measurements.

The internal electric field sensor antenna is inside the top end of the case. The large magnetic field coil is fairly central in the top half of the back of the instrument. Turn the PF5 for the highest reading.

To turn it off, push and hold for about 2 seconds. It will also automatically switch itself off after about 5 minutes use to save the battery power.

The LED scales are easy to read and use and are colour-coded for reasonable precautionary use. When two LEDs are both lit next to each other, then the exposure level is halfway between the two.

Technical Specifications:


  • Frequency range: 20Hz - 50kHz

  • A line of coloured LEDS shows the level

  • Electric fields range: 5 - 200 V/m

  • Magnetic fields range: 0.02 - 2.0 µT  

  • The following applies to electric & magnetic fields  » Resolution: 8 LEDs plus 7 middle points  » Accuracy: 50 to 2000 Hz ±10%  » Accuracy: 20 to 50000 Hz ±3 dB  » with a useable response from 15 Hz - 70 kHz

  • Battery: PP3 9V Alkaline or Rechargeable

  • Current: 16-23 mA

  • Battery life: 25 hours (normal alkaline) 

  • Low battery (6.7V) shown by red V/m LED

  • Size (mm): 110 x 63 x 21 (LxWxD)

  • Weight:140g incl.battery; 175g with pouch