Electric fence standards comport with human data and AC limits

Area of Science:

• Bioelectrics
• Electrical Safety Engineering
• Agricultural Safety

Background:

• Electric fences are vital in agriculture, reducing livestock-vehicle collisions.
• Current safety standards (IEC 60335-2-76, UL 69) focus on energy and RMS current, with limited direct correlation to cardiac effects.
• Ventricular fibrillation (VF) induction is a key concern for electrical safety.

Purpose of the Study:

• To compare existing electric fence safety standards (IEC, UL) with bioelectrically relevant units of charge and average current.
• To evaluate these standards against human VF induction data and IEC AC current limits.
• To assess the safety margins of electric fence energizer outputs.

Main Methods:

• Calculated delivered charge for IEC and UL limits across various pulse durations.
• Compared calculated charge to a charge-based safety model derived from human VF data.
• Assessed rapid pulsing standards (10-30 Hz) and compared outputs to AC current limits for VF risk, including TASER weapon outputs.

Main Results:

• IEC and UL normal rate standards for electric fence energizers are more conservative than human laboratory experiments suggest.
• IEC and UL rapid-pulsing standards are consistent with established IEC AC current limits for commercial pulse durations.
• Analysis included comparisons with TASER electrical weapon outputs.

Conclusions:

• Existing electric fence safety standards may be overly conservative for normal pulsing rates.
• Rapid pulsing standards are in line with existing AC current safety limits concerning VF risk.
• Further research into bioelectrically relevant metrics could refine electric fence safety standards.