Comply with new EPA standards by reducing engine idling time, and reap rewards - fewer costs and increased productivity.

As the Environmental Protection Agency’s (EPA) Tier IV program gets fully underway, companies must find cost-effective ways to comply with these rules.

The goal of the Tier IV program is to reduce diesel emissions from nonroad engines—including construction equipment such as backhoes and loaders.  

The EPA implemented clean air rules for diesel engines in 1994 with the Tier I standards, which called for re-ductions in emissions of nitrous oxide (NOx) and particulate matter (PM)—smog-forming substances— that can contribute to serious health problems. The EPA estimates that limiting diesel emissions will save over 12,000 lives and prevent 8,900 hospitalizations along with 1 million lost work days by 2030.

Diesel standards grew progressively stricter until the Tier IV program started earlier this year. The Tier IV/Stage III rules, which affect large nonroad diesel engines (those rated 174 horsepower and above), require a 50 percent cut in NOx and a 90 percent cut in PM. The new standard calls for tougher levels by 2014, reducing NOx levels by an additional 80 percent compared to the 2011 level. 

The burden to comply with the rules mostly falls on engine manufacturers, but equipment operators will also be affected. To meet the EPA’s new standards, manufacturers will be required to produce new engines with advanced emission-control technologies. The EPA estimates the anticipated costs for most categories of nonroad diesel equipment to be in the range of 1 to 3 percent of the total purchase price. 

Current blends of low-sulfur diesel (LSD) fuel will not be safe to use with the new engines. Ultra-low sulfur diesel (ULSD) blends have hit the market, with less than 15 percent parts per million (ppm) of sulfur. Some in the industry believe ULSD may not be compatible with biodiesel blends and will drive up fuel costs. 


The Effects of Idling


According to the North Central Texas Council of Governments, construction equipment idles for approximately 15 percent of all operating time. Annually, idling truck and locomotive engines consume over 1 billion gallons of diesel fuel and emit 11 million tons of carbon dioxide, 200,000 tons of NOx and 5,000 tons of PM, in addition to carbon monoxide and other toxic emissions, according to the EPA. 

The costs of idling can add up—it increases wear and tear on the engine, which contribute to maintenance costs and shortened engine life. Plus, the cost of wasted fuel can be significant.

Two main strategies that all industry sectors use include behavioral changes and technological solutions. However, the construction industry faces some unique challenges to reduce idling on the job. 


Challenges Unique to Construction



Road and nonroad diesel engines idle for very different reasons. Construction processes that may require idling include agitating cement, operating hydraulic systems and operating a boom lift. The Pennsylvania Department of Environmental Protection (DEP) has developed a draft of its nonroad diesel equipment anti-idling rules that includes the following exceptions for idling equipment:

  • To ensure the safe operation of the equipment
  • Testing, servicing, repairing or performing diagnostic procedures, including regeneration of a diesel particulate filter
  • Queuing for less than 15 minutes
  • An emergency or public safety capacity
  • Inspecting to verify that all equipment is in good working order, if idling is part of the inspection

Even though each job will bring with it different conditions and circumstances, you can still use proven strategies to reduce idling time. 


Behavioral Changes


EPA’s SmartWay Technology Program offers the following tips to help equipment operators reduce idling time:

  1. Begin a no-idling policy—Have operators turn off engines when not in use for five minutes or longer.
  2. Training—Provide information to operators on the impacts and adverse effects of idling over long durations.
  3. Financial incentives—Offer a bonus when your company keeps idling time below the national averages.
  4. Know your state and local laws—Many states and counties have anti-idling laws, and five states specifically target nonroad idling for construction equipment, including Connecticut, Massachusetts, New Jersey, Rhode Island and California. The American Transportation Research Institute (ATRI) provides a free listing of these rules at


Idling Reduction Technology



In addition to behavioral solutions, idling reduction technology can help reduce diesel emissions. This technology can be installed in vehicles, equipment or at a location, such as a parking area. While the initial investment can be costly, you can take advantage of federal tax incentives for installing this technology.

Idling reduction technologies that apply to construction equipment include devices that provide electricity, heat for an engine or environmental controls for a vehicle’s interior. Some idle controls include:

  • Fuel-operated heaters and direct-fired heaters can keep a cabin warm or cool by burning fuel from the main engine fuel supply or using a separate fuel reserve.
  • Auxiliary power units or generator sets are small engines that provide cooling, heating or electrical power to run accessories.
  • Electrification uses electric-powered components to provide heating or cooling without having to idle the main engine. Electric equipment can include on-board equipment, off-board equipment or a combination.

The EPA, along with the Department of Energy (DOE), evaluated the effectiveness and fuel-saving benefits of many idle reduction technologies. Find a list of verified idle reduction technologies, including a link to verified retrofit technologies, at


Customer Objectives


Many of your customers will be looking for ways to meet their own environmental objectives. They may expect you to prove you are doing all you can to protect the environment. If you contract with the federal government, the General Services Administration (GSA) writes green language into its contracts. GSA prefers to contract with environmentally-conscious companies for projects. In fact, the agency is currently developing a policy that will require its vendors and contractors to track and report their greenhouse gas emissions relating to the supply of products and services to the federal government. 

Idle time is unproductive time. Keeping idling to a minimum can be an advantage your company—you will conserve energy, reduce diesel emissions and save money.