Tier 4 Regulations | Tier 4  

Tier 4 Regulations 

Emissions and air quality
Off-road engines are responsible for 47% of particulate matter (PM) and 25% of NOx emissions from all mobile sources nationwide, according to the United States Environmental Protection Agency (EPA).

Air quality and health
Diesel exhaust contains small carbon particles and other toxic substances that are created during incomplete fuel burning process.  When inhaled repeatedly, these small particles may aggravate asthma and allergies or cause other serious health problems.

According to the EPA, the reduction in PM and NOx mandated by Tier 4 standards will provide enormous public health benefits.  EPA estimates that by 2030, controlling these emissions would annually prevent 12,000 premature deaths, 8,900 hospitalizations and one million work days lost.

Tier 4 regulations will be introduced in two phases:
• Tier 4 interim, began in 2011
• Tier 4 final, beginning in 2014
• Engines with less than 75 HP, beginning in 2013
• Engines between 75 and 175 HP, beginning in 2015

The pollutants
• NOx: Nitrogen monoxide and nitrogen oxide.  Produced during combustion when the engine is at its hottest.
• PM: Tiny carbon particles and other poisonous substances.  Created when not all fuel is burned during combustion, usually when the engine is cooler.

Reduction to date
NOx and PM have been reduced by 60 percent since the introduction of Tier 1 standards in 1996.

The goal
A 90 percent reduction in NOx and PM from Tier 3 standards.

Learn about how CASE is meeting these regulations.