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Portable Equipment FAQ

Q: How do I know if I own/operate portable equipment that should have a permit or registration? 

A: If you own or operate a diesel-fueled engine that is rated greater than 50 horsepower and does not propel a vehicle, you are required to obtain a district permit or registration to operate legally in California. The State Portable Equipment Registration Program (PERP) allows diesel engines that meet certification requirements to register in the program. Once a diesel engine has obtained a PERP registration, that diesel engine can operate in any of the 35 air districts in California without having to obtain a district permit. The Air District recommends obtaining a PERP registration in lieu of a district permit when possible; however, if a diesel engine operates in one location for more than twelve continuous months then an Air District permit is required.

Q: What are the requirements for gasoline or natural gas/propane fueled portable engines? 

A: All diesel engines having brake horsepower ratings of 50 or more that operate within Nevada, Sierra or Plumas Counties must be either permitted by the District, or if it is a portable engine, residing at any one location for less than 12 months, then it may be registered by the State in the Portable Equipment Registration Program in lieu of obtaining a District permit. The engine must comply with District regulations, including meeting requirements for having Best Available Control Technology (BACT).

If the gasoline, natural gas or propane fueled engine falls below the Air District’s minimum emission limits, then it is most unlikely that a permit will be necessary.

Q: What are examples of Portable Engines that must be permitted or registered? 

A: Any engine having a brake horsepower rating of 50 horsepower (HP) or more that does not provide motive power to a vehicle is required to have a permit from the District, or if the engine is portable it may instead have a Statewide PERP registration, issued by the California Air Resources Board. Portable engines include, but are not limited to, internal combustion engines used in the following: cranes, power generation, pumps, diesel pile-driving hammers, welding service or work-over rigs, well drilling, dredges on boats or barges, wood chippers, tactical support equipment, compressors, vacuum trucks, concrete pumpers, street sweepers, etc. etc.

Q: What are examples of Portable Equipment that must be permitted or registered? 

A: In addition to engines, any ancillary equipment that emits pollutants to the air exceeding 2 pounds per day should also be registered under the State-wide program; otherwise a separate District permit is required for operations within the Northern Sierra Air Quality Management District (NSAQMD). Portable equipment units include, but are not limited to, the following portable engine-associated units: confined and unconfined abrasive blasting operations, concrete batch plants sand and gravel screening, rock and pavement crushing and recycling tub grinders and trammel screens. Such equipment requires either an Air District Permit or a Statewide PERP registration.

Q: What is required of "Stationary" engines? 

A: The District requires a permit for all stationary engines greater than or equal to 50 horsepower (HP) for diesel fueled engines only.

The California Air Resources Board’s (CARB’s) Airborne Toxic Control Measure (ATCM) for Stationary Compression Engines Final Regulation Order has established requirements and compliance dates for diesel-fueled engines of greater than 50 HP.

Stationary engines falling under the requirements of the CARB ATCM or any District regulation must be permitted by the District to operate legally. The retrofit of the engine, or even its replacement, may be necessary to comply with applicable District regulations.

In addition, the Statewide PERP registration for some engines and equipment is not valid at any given location where other air contaminant emitting equipment, excluding engines, is operated as a stationary source and if the portable engine or equipment unit may be considered a part of the stationary source. District authorization must be obtained before operating at any specific location where the Statewide registration is not valid. The Statewide registration may also not be valid if certain hazardous or toxic materials are to be processed using PERP registered equipment. The District recommends reading the requirements of registration for your engine or equipment.

Q: What are the eligibility requirements to obtain a PERP registration? 

A: The Statewide Portable Equipment Registration Program (PERP), established in 1997, has emission standards that engines must satisfy. As a consequence all portable engines are not automatically eligible for registration. Only Final Tier 4 engines qualify for the PERP program.

Q: What does the State-Wide Portable Equipment Registration Program require me to do? 

A: In addition to having established emission limitations that must be satisfied to obtain a registration, the Statewide PERP program requires the conditions of registration are met. Included among the requirements are the following:

  • Unless you have designated the NSAQMD as your home district, you must notify the District within 2 days of coming to the NSAQMD if you intend to be in this Air District five days or more.
  • You must have a copy of the Certificate of Registration listing the equipment, and the registration requirements (e.g., the conditions of registration and operation) for the equipment, with the equipment available for immediate inspector review upon request.
  • The equipment must be properly labeled with a valid program registration label or sticker.
  • To be valid, registrations must reflect the current ownership of the engine or equipment.
Q: Where do I go to get my equipment registered in the State-Wide Portable Equipment Registration Program? 

A: All instructions, information (including fees), and application forms can be obtained by visiting the California Air Resource Board’s website.

Q: What engines or equipment cannot be registered? 

A: The following are commonly found engines and equipment that are not eligible for registration under the Statewide PERP program:

  1. any engine used to propel mobile equipment or a motor vehicle of any kind;
  2. any engine or equipment unit not meeting the definition of portable as defined in section 2452 (z) of this regulation (See the next question);
  3. any equipment unit and its associated engine determined by the Air Resources Board Executive Officer to qualify as part of a stationary source permitted by a district;
  4. any equipment unit and its associated engine determined by the District to qualify as part of a stationary source, which therefore requires permitting by the District.

In addition to (3), after a Statewide PERP registration is issued, the District may find that an equipment unit and its associated engine qualify as a part of a stationary source, and that the registration is therefore not valid.

Q: How is "Portable" equipment defined in The State-Wide Portable Equipment Registration Program? 

A: As defined by the Statewide PERP regulation, “Portable” means designed and capable of being carried or moved from one location to another. Indications of portability include, but are not limited to, wheels, skids, carrying handles, dolly, trailer, or platform. For the purposes of the regulation, dredge engines on a boat or barge are considered portable. The engine or equipment unit is not portable if any of the following are true:

  1. the engine or equipment unit or its replacement is attached to a foundation, or if not so attached, will reside at the same location for more than 12 consecutive months. The period during which the engine or equipment unit is maintained at a storage facility shall be excluded from the residency time determination. Any engine or equipment unit such as back-up or stand-by engines or equipment units, that replace engine(s) or equipment unit(s) at a location, and is intended to perform the same or similar function as the engine(s) or equipment unit(s) being replaced, will be included in calculating the consecutive time period. In that case, the cumulative time of all engine(s) or equipment unit(s), including the time between the removal of the original engine(s) or equipment unit(s) and installation of the replacement engine(s) or equipment unit(s), will be counted toward the consecutive time period; or
  2. the engine or equipment unit remains or will reside at a location for less than 12 continuous months if the engine or equipment unit is located at a seasonal source and operates during the full annual operating period of the seasonal source, where a seasonal source is a stationary source that remains in a single location on a permanent basis (at least two years) and that operates at that single location at least three months each year; or
  3. the engine or equipment unit is moved from one location to another in an attempt to circumvent the portable residence time requirements.
Q: How do I know what tier level my engine is? 

A: A “Tier 0 Engine” means a non-road engine that is not certified to any emission standard.

A “Tier 1 Engine” means a certified non-road engine, as defined in Title 17 of the California Code of Regulations section 93116.2(e), for the horsepower and year of manufacture as follows:

≥50 bhp and <100 bhp;1998 through 2003
≥100 bhp and <175 bhp;1997 through 2002
≥175 bhp and <300 bhp;1996 through 2002
≥300 bhp and <600 bhp;1996 through 2000
≥600 bhp and ≤750 bhp;1996 through 2001
>750 bhp;2000 through 2005A

“Tier 2 Engine” means a certified non-road engine, as defined in Title 17 of the California Code of Regulations section 93116.2(e), for the horsepower and year of manufacture as follows:

≥50 bhp and <100 bhp;2004 through 2007
≥100 bhp and <175 bhp;2003 through 2006
≥175 bhp and <300 bhp;2003 through 2005
≥300 bhp and <600 bhp;2001 through 2005
≥600 bhp and ≤750 bhp;2002 through 2005
>750 bhp;2006 through 2010
Q: What if an engine does not meet the certification requirements, or it cannot be retrofitted with the required control devices in order to obtain a registration? 

A: Diesel engine operation without a District permit or Statewide PERP registration may be a violation of both District rules and the State’s ATCM for diesel-fueled engines. As long as the engines are not permitted or registered, then each additional day during which the operation of the engine occurs may be counted as a new and additional violation. Engines that do not meet an emission certification standard are called “Tier 0” engines. The District is permitting and allowing the operation of such engines within the NSAQMD until January 1, 2010.

The State’s ATCM for portable diesel-fueled engines does not require Tier 0 diesel-fueled engines to meet new standards until January 1, 2010. For this reason the District may consider using its enforcement discretion to allow operation of a diesel-fueled engine that cannot currently be permitted or registered, provided:

  1. the un-permitted and unregistered status of any portable engines or equipment that is subject to permitting or registration is voluntarily disclosed to the District (i.e. the District wants to be advised on any non-complying engines or equipment),
  2. a settlement is reached on any discovered violations that have occurred,
  3. the economic benefit of not having a District permit is removed, and
  4. there is an enforceable commitment to come into compliance with all air pollution control requirements for all un-permitted or un-registered portable engines or equipment by no later than January 1, 2010.

If the engines are “discovered”, and not “disclosed” to the District, the settlement of a separate enforcement action may be necessary before the District will enter into an agreement to allow Tier 0 engine operation.

Q: What if I am caught without a district permit or registration? 

A: If you do not possess a District permit or Statewide PERP registration for your engine you are in violation of District Rule 501, Permit to Operate Regulations. If the engine is diesel fueled you are also in violation of the State’s Airborne Toxic Control Measure for Diesel Particulate Matter from Portable Engines Rated at 50 Horsepower and Greater. Among other requirements, this regulation requires that you obtain either a District permit or a Statewide PERP registration.

The District enforces both its rules and the State’s regulation. For each day that you were required to have a permit or registration and did not have one, you are strictly liable for up to $1,000 per day in civil penalties, and may be liable for up to $10,000 per day in civil penalties if the lack of a permit was due to negligent or intentional conduct.  Higher penalties may apply if in addition to not possessing a permit or registration the equipment emits pollutants in violation of applicable emission standards.  Finally, if a permit is sought then late permit application filing fees may apply.

In taking enforcement action the District will consider as factors in setting the penalty offer whether the violation was discovered by the District or if the violation was voluntarily disclosed, whether prompt action was taken to obtain a permit or registration, whether the violation was intentional or due to negligence, whether emission limitations were violated, and the benefit that accrued from the violation (e.g. avoided costs).

If the lack of a permit or registration “in-hand” is discovered, then the District will not allow operation of the equipment, unless either a District permit or a State registration has been applied for all company equipment subject to permitting/registration in within the NSAQMD, and an agreement on compliance has been reached. The District will take enforcement action for the discovered violation(s), but may elect not to take enforcement action on further operation of the equipment pursuant to a compliance agreement reached between the Operator and the District. If an application for a State PERP registration was made prior to discovery by the District this will be taken into consideration as a mitigating factor; however, the Operator is not absolved from having violated since having the registration prior to operation is a PERP requirement.

For violations disclosed to the District, the District may elect to not take enforcement action provided that a compliance agreement is reached between the Operator and the District and it is adhered to by the Operator to encourage future compliance.

Q: What if my portable engine(s) can meet the certification requirements, or control device retrofit requirements, but I don't yet have a permit or registration? 

A: You cannot legally operate, within the Northern Sierra Air Quality Management District, equipment that does not have required permits or registration unless you have a variance or have otherwise entered into a formal compliance agreement with the District. Enforcement action will be taken for the illegal operation of equipment even if you have applied for, but have not yet obtained a District permit or a Statewide PERP registration. You may apply for an expedited permit from the District to bridge the time period until your Statewide Portable Equipment Registration is received or you may enter into a compliance agreement whereby the District has additional assurance that a registration will be sought and obtained.

In taking enforcement action, the District will take into consideration efforts made to comply with air regulations and whether the violation or potential violation was self-disclosed or was discovered by the District.

For example, penalties from District enforcement action and late filing fees may apply for equipment that is “found”, in addition to normal permit fees. Conversely, the District may elect to not seek any penalties for violations that are voluntarily disclosed and where an agreement with the District provides some assurance to the District that corrective action will be taken.

Q: What about portable equipment that I may rent? 

A: Rental equipment is required to meet the same permitting or registration requirements as non-rental equipment, except that when authorized by the Air Resources Board, local district notification is not required for rental equipment of 200 HP or less. The engine and associated equipment should be permitted or registered by the rental company.

If you rent portable equipment you should receive a copy of the registration certificate, including requirements of registration (e.g., the conditions of registration and operation), from the rental company and a certification label should be affixed to the equipment. You share responsibility with the rental company for making sure the equipment is properly permitted or registered prior to your operating the equipment. If the District finds that a registration is not on-hand and/or the equipment sticker showing that the equipment is properly registered, the District may find the renter or the rental company, or both, to be in violation of program requirements.

Q: Where can I obtain further information about these matters? 

A: Statewide Portable Equipment Registration Program:  Information regarding the Statewide Portable Equipment Registration Program and Application Forms can be obtained by calling (916) 324-5869, via e-mail at portable@arb.ca.gov, or from the California Air Resources Board’s website. Portable Equipment ATCM:  Information concerning the State’s Airborne Toxic Control Measure for Diesel Particulate Matter from Portable Engines Rated at 50 Horsepower and Greater is available from the California Air Resources Board’s website. Northern Sierra Air Quality Management District Permitting:  Permitting information may be obtained by contacting the District at (530) 274-9360, or from the District webpage. Stationary Compression Engine ATCM:  Information concerning the State’s Airborne Toxic Control Measure for Stationary Compression Engines is available from the California Air Resources Board’s website.

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