Siemens SIMATIC RF600 System Manual page 23

The horizontal line at 41.25 V/m marks the "safety limit value".
Distance to transmitter antenna [m]
If the transmit power is set lower than the highest permitted value (4 W EIRP), the "safety
distance" reduces correspondingly.
The values for this are as follows:
Generally a safety distance of at least 0.2 m should be maintained.
Note
Reduced maximum radiated power with RF600 readers
SIMATIC RF610R and RF615R (FCC) readers have a maximum transmit power of 400 mW.
The radiated power depends on the antenna cable and the antenna used, but must not
exceed 2 W ERP.
The SIMATIC RF650R (FCC) reader has a maximum transmit power of 1 W. The radiated
power therefore depends on the antenna cable and the antenna used, but must not exceed
4 W EIRP.
The SIMATIC RF680R (FCC) reader has a maximum transmit power of 2 W. The radiated
power therefore depends on the antenna cable and the antenna used, but must not exceed
4 W EIRP.
The SIMATIC RF685R (CC) reader has a maximum transmit power of 2 W. This means that
the safety distance is at least 0.12 m.
When using Siemens products and with suitable configuration via the WBM, the high limits
cannot be exceeded.
SIMATIC RF600
System Manual, 06/2019, J31069-D0171-U001-A22-7618
1
5
Radiated power EIRP [W]
4.0
<2.5
2.3 Safety distance to transmitter antenna
Feld strength [V/m]
10.9
2.2
Safety distance to transmitter antenna [m]
Safety Information
% of limit value
26
5.3
0.26
>0.20
23