Rules and Regulations

SDG&E and all electric utilities in California are required to prune or clear vegetation close to energized electrical equipment, structures and high-voltage power lines for public safety and electric system reliability.

SDG&E performs regular power line tree safety activities in accordance with industry standards, guidelines and acceptable procedures that help to reduce widespread outages or fire caused by overgrowth of trees or other vegetation.

California Public Utilities Commission (CPUC) General Order 95, Rule 35GO 95, Rule 35, requires an 18 inch radial clearance be maintained at all times between vegetation and high-voltage conductors between 750 and 22,500 volts.

The clearance requirements increase for conductors carrying transmission voltages (69,000 volts and greater). GO 95, Rule 35, applies to the entire SDG&E territory year round, though certain state law supersedes Rule 35 in a State Responsibility Area (SRA).

Public Resource Code (PRC), Section 4292This law is administered by the California Department of Forestry and Fire Protection (known as Cal Fire and formerly known as CDF). PRC 4292 is a minimum 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 removed. 

Public Resource Code (PRC), Section 4293This law is administered by the California Department of Forestry and Fire Protection (known as Cal Fire and formerly known as CDF). PRC 4293 requires a 4 foot radial clearance be maintained at all times for conductors between 2,400 and 72,000 volts. The clearance requirements increase as the voltage increases. PRC 4293 applies year round in San Diego County in those areas designated as a SRA, where Cal Fire is the primary fire suppression agency.

Cal OSHA, Title 8, Article 37States that no person shall come within six to 16 feet of energized high-voltage power lines, and that no boom type of lifting or hoisting equipment shall come within 10 to 20 feet, depending on the voltage of the high-voltage power lines.

This also means there cannot be personnel or equipment in trees, such as avocado or other fruit trees, six feet or less from the high-voltage power lines.

Cal Penal Code, Section 385Makes it a crime for an unauthorized person to use tools or other equipment within six feet of high-voltage lines.

Federal Energy Regulatory Commission (FERC) and North American Electric Reliability Corporation (NERC)In addition to state requirements, the FERC and NERC require that utilities adopt and maintain minimum clearance standards between vegetation and transmission voltage power lines. These clearances vary depending on voltage. In some cases, the minimum clearances required in state regulations are greater than the federal requirement.