Specifications

B-field Exposure From Induction Cooking Appliances 42
Figure 31: Influence of pot characteristics (bottom diameter, shape, bottom flatness
and material grade) on the B-field measured. a) Normalized B-field measured for each
pot (pots ranked from smallest to largest bottom diameter). b) Standard set of pots; the
measured B-field decreases when the bottom diameter increases. c) For four pots with the same
bottom diameter, the B-field measured depends on the pot characteristics (material, flatness).
Measurements using appliance 3; the pots are centered and filled to 50 % of their capacity with
tap water; lids used when available.
the worst-case scenario depends strongly on the pot, hob and appliance combination (see Chapter
6.1.1).
6.0.7 Negligible Parameters
The following parameters have also been evaluated and can be neglected since their contribution
amounts to less than 5 % of the B-field variations. These include the volume of water in the
pot, content of the pot (e.g., tap water, salt-water, vegetable oil), lid on pot, handle position,
proximity to a magnet or paramagnetic object (cooking utensil).
Volume of water in the pot Stable operation conditions are reached when the water boils,
i.e., after approximately 4 to 6 minutes (H
2
O phase transition). While the water is boiling,
the B-field is almost constant (see Figure 32) and the field variations remain less than ±2.45 %
for appliances 1, 2 and 3. Figure 32 shows that for all three appliances, the B-field measured
does not significantly depend on the duration of the measurement (the power supplied by the
appliance is stable over time). Moreover, the B-field measured does not depend on the volume
of water in the vessel, except when there is almost no water remaining in the pot (in that
case the pot quickly becomes very hot and the B-field increases rapidly before the appliance
automatically stops).