Safety Distance To Transmitter Antenna; Safety Distance Between Transmitter Antenna And Personnel - Siemens SIMATIC RF600 System Manual

Note
User responsibility for modified product
As a user of the modified product, you accept responsibility for use of the complete RFID
product comprising both SIMATIC RF600 components and third-party RFID components.
This particularly applies to modification or replacement of:
● Antennas
● Antenna cables
● readers
● Power supply units with connection cables
2.3

Safety distance to transmitter antenna

2.3.1

Safety distance between transmitter antenna and personnel

For antenna configurations where it is possible to be briefly or constantly within the
transmission range of the antennas, as in loading ramps, for example, minimum distances
must be maintained.
Limits
The ICRP (International Commission of Radiological Protection) has worked out limit values
for human exposure to HF fields that are also recommended by the ICNIRP (International
Commission of Non Ionizing Radiological Protection). In German legislation on emissions
(since 1997), the following limit values apply. These can vary according to frequency:
Frequency f [MHz]
10 - 400
400 - 2.000
2.000 - 300.000
The limit values for the 900 MHz reader antenna alternating field are thus:
Electrical field strength: E = 41.25 V/m
Magnetic field strength: H = 0.111 A/m
HF power density: E x H = 4.57 W/m
SIMATIC RF600
System Manual, 06/2010, J31069-D0171-U001-A10-7618
Electrical field strength E [V/m]
27,5
1.375 x f
1/2
61
2
Draft Version 02.06.2010
Safety Information
2.3 Safety distance to transmitter antenna
Magnetic field strength H [A/m]
0,073
0.0037 x f
1/2
0,16
17