Public Safety Power Shutoff (PSPS) Events

Public Safety Power Shutoff Events

Your local energy company may need to turn off power during extreme weather or wildfire conditions. This is called a public safety power shutoff (PSPS). If you plan on using an emergency generator to power your home or business during a PSPS event, here are some tips for staying safe and compliant with state rules and requirements administered by the Air Pollution Control District.

Emergency Generators For Residents and Businesses 

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For Residents | En Español

For Businesses

Backup generators aren’t for everyone. Consider safety, noise, and cost along with your emergency power needs. Diesel exhaust contains toxic air contaminants and has been linked to lung cancer and other adverse health effects. Because of those concerns, there are permitting and registration requirements.

What are the permit requirements for diesel backup generators?

  • An APCD permit is required for diesel engines 50 bhp or greater.
  • You can use a permitted diesel backup generator during a PSPS event and be compliant with air quality requirements if:
    • You are within an outage area, and
    • You use the generator only when the outage has occurred and only during the outage.

What are the alternatives to diesel backup generators?

  • Battery and solar generators are the cleanest, safest options.
  • Other alternatives to diesel include gasoline, natural gas, and propane.

What are some precautions for using backup generators?

  • Never use a fuel-powered generator inside your home. Good ventilation is required because of the pollutants that these generators produce.
  • Be a good neighbor. Consider the effects of noise and exhaust before installing.
  • If you use a generator during a wildfire, we recommend powering a HEPA air purifier to provide a clean air room for your family.

Agricultural Engines

  • Agricultural engines are subject to state rules and requirements administered by the APCD.
    • An APCD agricultural registration is required for agricultural diesel engines 50 bhp or greater.
    • Agricultural engines must meet Tier 4 final standards.
    • CUPA may have requirements for fuel storage; contact them before installing:



  1. Is a permit required for a generator engine rated less than 50 bhp? No, engines rated less than 50 bhp are exempt from APCD permitting requirements pursuant to Rule 202.F.1.e and 202.F.1.f.
  2. Is a permit required for a spark ignited (natural gas, propane, gasoline, etc.) generator engine? Spark ignited engines used exclusively for emergency electrical power generation are exempt from APCD permit requirements if the engine operates no more than 200 hours per year pursuant to Rule 202.F.1.d.  Spark ignited emergency standby generator engines that operate more than 200 hours per year require an APCD permit.
  3. What are the costs associated with an APCD permit for diesel engines 50bhp or greater? Costs involved include a $420 application fee, plus an approximately $4/HP fee, a $459 annual emission fee, and a $429 reevaluation fee (every three years). Agricultural engines are subject to a single $258 annual fee.

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