Welch Allyn 4200B Directions For Use Manual page 58

50
Recommended Separation Distances Between Portable and Mobile RF Communications Equipment and the 420 Series Spot
The 420 Series Spot Vital Signs is intended for use in an electromagnetic environment in which radiated RF disturbances are controlled. The
customer or user of the 420 Series Spot Vital Signs can help prevent electromagnetic interference by maintaining a minimum distance between
portable and mobile RF communications equipment (transmitters) and the 420 Series Spot Vital Signs as recommended below, according to the
maximum output power of the communications equipment.
Rated Max. Output
Power of Transmitter
(W)
0.01
0.1
1
10
100
For transmitters rated at a maximum output power not listed above, the recommended separation distance d in meters (m) can be estimated
using the equation applicable to the frequency of the transmitter, where P is the maximum output power rating of the transmitter in watts (W)
according to the transmitter manufacturer.
Note 1: At 80 MHz and 800 MHz, the separation distance for the higher frequency range applies.
Note 2: These guidelines may not apply in all situations. Electromagnetic propagation is affected by absorption and reflection from structures,
objects, and people.
Vital Signs
Separation Distance According to Frequency of Transmitter (m)
150 kHz to 80 MHz
P
d = (1.17)
0.11667
0.36894
1.1667
3.6894
11.667
80 MHz to 800 MHz
P
d = (1.17)
0.11667
0.36894
1.1667
3.6894
11.667
Welch Allyn Spot Vital Signs
800 MHz to 2.5 GHz
P
d = (2.33)
0.23333
0.73785
2.3333
7.3785
23.333