Many small businesses use internal combustion engines as part of their business operations.  Depending on their size, age, fuel type and how they are used, these engines may be subject to DEP and/or EPA air regulations and possibly require certification or a permit, such as DEP's GP-9.

Emergency Generators

Even if you only use the engines at your company for emergency power generation, you may still need a permit or certification and special recordkeeping and reporting may be required.

  • Both the Pennsylvania DEP and U.S. EPA regulate emergency generators.
  • Pennsylvania DEP’s Air Quality Permit Exemption List includes an exemption for engines rated at less than 100 brake horsepower (bhp) [#4, page 4]. Engines greater than 100 bhp may also be exempt from PA DEP permitting depending on their size and current and intended use.
  • Additional federal requirements under EPA's RICE regulations for newly purchased generators include:
    • Unlimited use during emergencies
    • Non-emergency use limited to 100 hours per year
    • A valid U.S. EPA Certificate of Conformity
    • Requirements based on the type of fuel used.
  • Additional federal EPA requirements may also apply to existing emergency generators depending on their size, use, fuel type and date manufactured.
  • As of May 4, 2016, back-up engines that wish to continuing to operate under emergency demand response will be considered non-emergency engines and must meet the regulatory requirements including numerical emission limits, or work practice standards, notifications, and performance testing that may apply. Learn More.