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Table 2 IEEE 2014 [11] contact current MPEs for the lower tier (Zone 0, unrestricted environments where members of the general public may be present) and the upper tiers (Zone 1, restricted environments wherein persons are subject to an RF safety program and Zone 2, restricted experts only (REO) environment wherein persons are subject to an RF safety program and are deemed to be highly qualified for working in the vicinity of specific high intensity RF environments)

From: Perspectives on setting limits for RF contact currents: a commentary

 

Zone 0 (unrestricted environments)

Zone 1 (restricted environments)

Zone 2 (REO)

Frequency (MHz)

0.1–3

3–30

30–110

0.1–3

3–30

30–110

0.1–110

Contact, grasp

100

100 (f/3)0.3

200

250

Contact, touch

16.7

16.7 (f/3)0.3

33.4

50

50 (f/3)0.3

100

  1. Tabulated value are rms values; f frequency in MHz
  2. Limits apply to current flowing between the body and a grounded object that may be contacted by the person
  3. The averaging time for determination of compliance is 6 min (Zone 1 and Zone 2) and 30 min (Zone 0) for induced currents, 1 s for touch current (Zone 0 and Zone 1), and 6 min for grasp contact current
  4. Calculated values for personnel in Zone 0 and Zone 1 are capped at the 30 MHz values since there is insufficient data to extrapolate above 30 MHz
  5. Light “brush” contact may result in arcs and shock and burn even at 50 mA and should be avoided, especially with long objects such as cranes or cables
  6. For definition of each of the zones, see 3.1 in the IEEE standard
  7. Restricted expert only access Zone 2 may be established only when mission essential and only when all personnel who are allowed access are expert on the particular system and informed that fingertip touch contact is to be avoided. Grasp is the appropriate method of contact
  8. The ceiling values (temporal peak values as measured with accepted instruments) for induced current are 220 mA for Zone 0 (for a maximum duration of 75.3 s) and 500 mA for Zone 1 and Zone 2 (for a maximum exposure duration of 14.4 s)