Vegetation management safety rules and regulations
For public safety and electric system reliability, all electric utilities in California are required to prune or remove vegetation to maintain clearances for electric equipment, including power lines, transmission towers and power poles.
Here are some of the key requirements that apply to our vegetation management activities to remove electric shock hazards, reduce fire risk and help prevent power outages.
- California Public Utilities Commission (CPUC) General Order 95, Rule 35
GO 95, Rule 35, requires an 18-inch radial clearance always be maintained between vegetation and high-voltage conductors (750 volts to 22,500 volts).
The clearance requirements increase for conductors carrying transmission voltages (69,000 volts and greater). GO 95, Rule 35, applies throughout SDG&E’s service area year-round, though certain state laws supersede Rule 35 in State Responsibility Areas (SRAs).
- CPUC Decision 17-12-024
In a December 2017 decision, the CPUC adopted new fire safety regulations, including a new standard requiring utilities to maintain a minimum of 4 feet of clearance between trees and power lines in high fire-threat areas. In January 2018, the CPUC also approved a statewide Fire-Threat Map to help prioritize fire hazard areas and implement the new fire prevention rules. Maps detailing the High Fire-Threat District (HFTD) are posted online as part of an overview of the CPUC’s fire safety proceedings.
- Public Resources Code (PRC), Section 4292
This law is administered by the California Department of Forestry and Fire Protection, known as CAL FIRE. PRC 4292 requires a minimum clearance of 10 feet around the base of the pole cleared of all flammable vegetation down to bare soil. Limbs within the 10-foot radius are removed up to 8 feet above ground. All dead branches below the cross arms and within the 10-foot radius must be removed.
- Public Resources Code (PRC), Section 4293
This law is administered by the California Department of Forestry and Fire Protection, known as CAL FIRE. PRC 4293 requires a 4-foot radial clearance always be maintained for conductors between 2,400 volts and 72,000 volts. The clearance requirements increase as the voltage increases. PRC 4293 applies year-round in San Diego County areas designated as State Responsibility Areas (SRAs), where CAL FIRE is the primary fire suppression agency.
- Cal/OSHA, Title 8, Article 37
This regulation is administered by the California Division of Occupational Safety and Health, better known as Cal/OSHA. It states that no person shall come within 10 feet to 16 feet of energized high-voltage power lines, and that no boom-type lifting or hoisting equipment shall come within 10 feet to 20 feet, depending on the voltage of the high-voltage power lines.
It also prohibits personnel and equipment from being in trees, such as avocado or other fruit trees, that are 10 feet or less from high-voltage power lines.
- Penal Code (PEN), Section 385
This law makes it a crime for any unauthorized person to use tools or other equipment within 6 feet of high-voltage lines.
- Federal Reliability Standard FAC-003-4
In addition to meeting state requirements, utilities must meet federal reliability standards for clearances between vegetation and transmission lines. These standards for the nation's bulk-power system are set by the Federal Energy Regulatory Commission (FERC) and the North American Electric Reliability Corporation (NERC). The Transmission Vegetation Management Reliability Standard, FAC-003-4, establishes a minimum clearance that must be maintained at all times between trees and transmission line rights-of-way. Federally required clearances vary depending on voltage and in some cases are less stringent than state standards.
Get a bird’s-eye view of vegetation clearance requirements for urban areas, rural areas and power poles.
High Fire-Threat District (HFTD) map helps prioritize fire hazard areas.
Federal standards apply to clearances for transmission line rights-of-way.