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Environmental Management Assistance Program


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.

Final Rule for Operating Emergency Engines for Demand Response

On August 4, 2022, EPA removed vacated provisions to reflect a 2015 court ruling regarding the RICE NESHAP and NSPS for using emergency engines for demand response. The court vacated provisions in the regulations specifying that emergency engines could operate for emergency demand response or during periods where there is a deviation of voltage or frequency.


Need Help?

Contact EMAP for free and confidential assistance:

  • Understanding how the regulations apply to your new or existing engine or emergency generator

  • Applying for permit exemptions or permits, if needed
Jeremy Hancher is the EMAP Program Manager located at the Widener University SBDC.  He holds over 15 years of experience in environmental compliance, environmental policy, and program management.  He is proud to be the team lead of the award-winning EMAP program which provides free and confidential environmental assistance to the Pennsylvania small business community in fulfillment of the requirements of the Pennsylvania Air Pollution Control Act and Section 507 of the federal Clean Air Act.
In 2015, Jeremy was part of the team effort when EMAP was recognized by US EPA Administrator Gina McCarthy for Outstanding Accomplishments by a State Small Business Environmental Assistance Provider in Providing Technical Environmental Assistance to the Small Business Community. Jeremy holds a Bachelor’s degree from the University of Pittsburgh, a Master’s degree from the University of Pennsylvania, and a certificate from the Wharton School.