Non-road Diesel Engine Certification Tier Chart Categories Topics Enforcement Programs Portable Equipment Registration Program (PERP) Type Information Contact Portable Equipment Registration Program (PERP) Email portable@arb.ca.gov Phone see list of contacts The PERP eligibility requirements take effect six months after the federal and CARB non-road engine emission standards for engine manufacturers change -- as shown: Documents Tier Color Chart- Off-Road Dieslel Stds TIER_COLOR_CHART_OFF_ROAD_DIESEL_STDS_R.PDF · 54 KB Related Resources PSIP Regulation Test Method 435 Automated License Plate Reader