All 12 Ham Radio Amateur Extra questions for E0 Safety with the correct answers marked, from the official 2024-2028 question pool. Test yourself with the free practice exam.
E0A01
What is the primary function of an external earth connection or ground rod?
A. Prevent static build up on power lines
B. Lightning charge dissipation ✓
C. Reduce RF current flow between pieces of equipment
D. Protect breaker panel from power surges
E0A02
When evaluating RF exposure levels from your station at a neighbor’s home, what must you do?
A. Ensure signals from your station are less than the controlled maximum permissible exposure (MPE) limits
B. Ensure signals from your station are less than the uncontrolled maximum permissible exposure (MPE) limits ✓
C. Ensure signals from your station are less than the controlled maximum permissible emission (MPE) limits
D. Ensure signals from your station are less than the uncontrolled maximum permissible emission (MPE) limits
E0A03
Over what range of frequencies are the FCC human body RF exposure limits most restrictive?
A. 300 kHz - 3 MHz
B. 3 - 30 MHz
C. 30 - 300 MHz ✓
D. 300 - 3000 MHz
E0A04
When evaluating a site with multiple transmitters operating at the same time, the operators and licensees of which transmitters are responsible for mitigating over-exposure situations?
A. Each transmitter that produces 20 percent or more of its MPE limit in areas where the total MPE limit is exceeded
B. Each transmitter operating with a duty cycle greater than 25 percent
C. Each transmitter that produces 5 percent or more of its MPE limit in areas where the total MPE limit is exceeded ✓
D. Each transmitter operating with a duty cycle greater than 50 percent
E0A05
What hazard is created by operating at microwave frequencies?
A. Microwaves are ionizing radiation
B. The high gain antennas commonly used can result in high exposure levels ✓
C. Microwaves are in the frequency range where wave velocity is higher
D. The extremely high frequency energy can damage the joints of antenna structures
E0A06
Why are there separate electric (E) and magnetic (H) MPE limits at frequencies below 300 MHz?
A. The body reacts to electromagnetic radiation from both the E and H fields
B. Ground reflections and scattering cause the field strength to vary with location
C. E field and H field radiation intensity peaks can occur at different locations
D. All these choices are correct ✓
E0A07
What is meant by “100% tie-off” regarding tower safety?
A. All loose ropes and guys secured to a fixed structure
B. At least one lanyard attached to the tower at all times ✓
C. All tools secured to the climber’s harness
D. All circuit breakers feeding power to the tower must be tied closed with tape, cable, or ties
E0A08
What does SAR measure?
A. Signal attenuation ratio
B. Signal amplification rating
C. The rate at which RF energy is absorbed by the body ✓
D. The rate of RF energy reflected from stationary terrain
E0A09
Which of the following types of equipment are exempt from RF exposure evaluations?
A. Transceivers with less than 7 watts of RF output
B. Antennas that radiate only in the near field
C. Hand-held transceivers sold before May 3, 2021 ✓
D. Dish antennas less than one meter in diameter
E0A10
When must an RF exposure evaluation be performed on an amateur station operating on 80 meters?
A. An evaluation must always be performed ✓
B. When the ERP of the station is less than 10 watts
C. When the station’s operating mode is CW
D. When the output power from the transmitter is less than 100 watts
E0A11
To what should lanyards be attached while climbing?
A. Antenna mast
B. Guy brackets
C. Tower rungs
D. Tower legs ✓
E0A12
Where should a shock-absorbing lanyard be attached to a tower when working above ground?
A. Above the climber’s head level ✓
B. To the belt of the fall-arrest harness
C. Even with the climber's waist
D. To the next lowest set of guys