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Compliance Requirements for Stationary Engines

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RICE Rule requirements are complex – but they are similar for several groups of engines, as summarized in the tables below.

Key Definitions for Terms Used in Compliance Summary Tables

  • CI: Compression Ignition (diesel)
  • SI: Spark Ignition (gas including natural gas, landfill gas, gasoline, propane, etc.)
  • 2SLB: 2-stroke lean burn
  • 4SLB: 4-stroke lean burn
  • 4SRB: 4-stroke rich burn
  • 4S: 4-stroke
  • LFG/DG: landfill gas/digester gas
  • ULSD: Ultra Low Sulfur Diesel

Notes:

  • 2-stroke: power cycle completed in 1 revolution of crankshaft
  • 4-stroke: power cycle completed in 2 revolutions of crankshaft
  • Lean burn: higher air/fuel ratio (fuel-lean)
  • Rich burn: lower air/fuel ratio (fuel-rich)

Compliance Requirements by Engine Subcategory

Engine Subcategory Compliance Requirements

Existing non-emergency:

  • CI ≥100 HP at major source
  • CI >300 HP at area source
  • SI 100-500 HP at major source
  • Initial emission performance test
    • Subsequent performance testing every 8,760 hours of operation or 3 years for engines >500 HP (5 years if limited use)
    • Operating limitations - catalyst pressure drop and inlet temperature for engines >500 HP
    • Notifications
    • Semiannual compliance reports (annual if limited use)

Existing non-emergency CI >300 HP:

  • Ultra low sulfur diesel (ULSD)
  • Crankcase emission control requirements
  • Existing non-emergency SI 4SLB/4SRB >500 HP at area source used >24 hours/year and not in remote area
  • Initial and annual catalyst activity checks
  • High temperature engine shutdown or continuously monitor catalyst inlet temperature
  • Notifications
  • Semiannual compliance reports
Engine Subcategory Compliance Requirements

Existing emergency/black start:

  • <100 HP at major source
  • ≤500 HP at major source
  • All at area source

Existing non-emergency:

  • <100 HP at major source
  • CI ≤300 HP at area source
  • SI ≤500 HP at area source
  • SI 2SLB >500 HP at area source
  • SI LFG/DG >500 HP at area source
  • SI 4SLB/4SRB >500 HP at area source used ≤24 hours/year or in remote area
  • Operate/maintain engine & control device per manufacturer’s instructions or owner-developed maintenance plan
  • May use oil analysis program instead of prescribed oil change frequency
  • Emergency engines must have hour meter and record hours of operation
  • Keep records of maintenance
  • Notifications not required
  • Reporting and ULSD for emergency engines used for local reliability
Engine Subcategory Compliance Requirements

Existing non-emergency:

  • SI 4SRB >500 HP at major source

New non-emergency:

  • SI 2SLB >500 HP at major source
  • SI 4SLB >250 HP at major source
  • SI 4SRB >500 HP at major source
  • CI >500 HP at major source
  • Initial emission performance test
    • Subsequent performance testing semiannually (can reduce frequency to annual) (subsequent performance testing required for 4SRB engine complying with formaldehyde % reduction standard if engine is ≥5000 HP)
    • Operating limitations - catalyst pressure drop and inlet temperature
    • Notifications
    • Semiannual compliance reports
Engine Subcategory Compliance Requirements
  • New emergency/limited use >500 HP at major source
  • Initial notification
  • New non-emergency LFG/DG >500 HP at major source
  • Initial notification
  • Monitor/record fuel usage daily
  • Annual report of fuel usage

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Emission Standards: Existing RICE at Major Sources

HP Engine Subcategory
Non-emergency Emergency
CI SI 2SLB SI 4SLB SI 4SRB SI LFG/DG
<100 Change oil and filter and inspect cleaner (CI) or spark plugs (SI) every 1,000 hours of operation or annually; inspect hoses and belts every 500 hours of operation or annually Change oil/filter & inspect hoses/belts every 500 hours or annually; inspect air cleaner (CI) or spark plugs (SI) every 1,000 hours or annually
100-300 230 ppm CO 225 ppm CO 47 ppm CO 10.3 ppm CH2O 177 ppm CO
300-500 49 ppm CO or 70% CO reduction
>500 23 ppm CO or 70% CO reduction No standards No standards 350 ppb CH2O or 76% CH2O reduction No standards No standards
Note: Existing limited use engines >500 HP at major sources do not meet any emission standards. Existing black start engines ≤500 HP at major sources must meet work practice standards.

Emission Standards: Existing RICE Located at Area Sources

HP Engine Subcategory
Non-emergency Emergency or Black Start
CI SI 2SLB SI 4S in remote areas SI 4S not in remote areas SI LFG/DG
≤300 Change oil/filter & inspect air cleaner every 1,000 hours or annually; inspect hoses/belts every 500 hours or annually Change oil/filter, inspect spark plugs, & inspect hoses/belts every 4,320 hours or annually Change oil/filter, inspect spark plugs, & inspect hoses/belts every 1,440 hours of operation or annually Change oil/filter, inspect spark plugs, & inspect hoses/belts every 1,440 hours of operation or annually Change oil/filter, inspect spark plugs, & inspect hoses/belts every 1,440 hours of operation or annually Change oil/filter & inspect hoses/belts every 500 hours or annually; inspect air cleaner (CI) or spark plugs (SI) every 1,000 hours or annually
300-500 49 ppm CO or 70% CO reduction*
>500 23 ppm CO or 70% CO reduction Change oil/filter, inspect spark plugs, & inspect hoses/belts every 2,160 hours of operation or annually if engine used >24 hrs/yr:

4SLB: Install oxidation catalyst

4SRB: Install NSCR

Emission Standards: New RICE Located at Major Sources

HP Engine Subcategory
Non-emergency Emergency
CI SI 2SLB SI 4SLB SI 4SRB SI LFG/DG
<250 Comply with CI NSPS Comply with SI NSPS Comply with SI NSPS Comply with SI NSPS Comply with SI NSPS Comply with CI/SI NSPS
250-500 14 ppm CH2O or 93% CO reduction
>500 580 ppb CH2O or 70% CO reduction 12 ppm CH2O or 58% CO reduction 350 ppb CH2O or 76% CH2O reduction No standards No standards
Note: New limited use engines >500 HP at major sources do not meet any emission standards under the NESHAP
New RICE Located at Area Sources: meet Stationary Engine NSPS
  • CI: part 60 subpart IIII
  • SI: part 60 subpart JJJJ

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Determining RICE New Source Performance Standards (NSPS) Compliance Requirements

The NSPS rules include two alternative compliance approaches:

  1. Operators comply by purchasing an engine certified by the manufacturer. 
  2. For spark ignition engines, operators comply by meeting emission limits for an engine not certified by the manufacturer.

If you own or operate a Compression Ignition engine you are subject to the NSPS at 40 CFR 60, Subpart IIII if the engine was:

  • Constructed (ordered) after July 11, 2005, and manufactured after April 1, 2006 (July 1, 2006 for fire pump engines), or
  • Modified or reconstructed after July 11, 2005.
  • Except for engines > 30 liters per cylinder (l/cyl) displacement, performance testing is not required - you achieve compliance by:
    • purchasing a new engine that has been certified by EPA, and
    • installing, configuring, operating, and maintaining the engine per the manufacturer’s instructions.

If you own or operate a Spark Ignition engine you are subject to the NSPS at 40 CFR 60, Subpart JJJJ if the engine was:

  • Constructed (ordered) after 6/12/2006 and the engine is
    • >500 HP manufactured on/after 7/1/2007 (except lean burn 500≤HP<1,350)
    • lean burn 500≤HP<1,350 manufactured on/after 1/1/2008
    • <500 HP manufactured on/after 7/1/2008
    • emergency >25 HP manufactured on/after 1/1/2009
    • modified/reconstructed after 6/12/2006.
  • For certain Spark Ignition engines manufactured on/after July 1, 2008, the engine manufacturer is required to certify that the engine meets emission limits. As the owner or operator of the engine you can comply by purchasing a certified engine, and operating it according to manufacturer’s instructions. These SI engine types include:
    • ≤ 25 HP,
    • gasoline engines >25 HP, and
    • rich burn LPG engines >25 HP.
  • For other Spark Ignition engines, EPA made it optional for the manufacturer to certify that their engines meet the applicable emission limits. Owners or operators can comply either by purchasing an engine that the manufacturer has voluntarily certified, or by conducting performance testing to demonstrate that the engine meets the applicable emission limits.

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