No other facility type has as much at stake as a hospital to maintain a consistent power supply. For decades, high-horsepower diesel engine generators have supplied the mission-critical backup power to health care facilities throughout the world.

However, recent regulations by the Environmental Protection Agency (EPA) have placed limits on allowable exhaust emissions and changed the rules applying to certain types of system operations.

The responsibility for compliance lies both with the owner and engine manufacturer.

Emissions reductions

Hospitals may be more accustomed to federal and state regulations than any other industry. Whether it's the disposal of toxic waste or compliance with the International Building Code's seismic and fire protection regulations, hospitals and health care providers always have been at the top of the list for the development of regulations.

The EPA added to this list in 2011 by introducing its Tier 4 interim (Tier 4I) certification requirements, ushering in tighter emission reductions for high-horsepower diesel generator sets.

Of particular interest to those who rely on these mission-critical generators for emergency backup is the regulation's stance on emergency use. Tier 4I requires all operators who seek to run new generators for nonemergency use — whether for extended long-term testing and maintenance, demand response, storm avoidance, peak shaving or prime power — to deploy units that meet the new emission-reduction levels.

For many hospital operators, the new regulations are a departure from the previous grandfather clause that allowed unlimited nonemergency operation under the EPA's previous Tier 2 certification for high-horsepower generator sets.

The EPA established defined operating limits when establishing Tier 4 standards many years ago. In January 2013, the EPA revised the language defining limits like the 100-hour rule as it applies to both new and existing generator engines.

For some hospitals, the time has come when achieving Tier 4I certification outweighs the negative impacts of potential operating fines, and the prospect of readying for future emission reductions becomes a near-term priority.

Hospitals located in regions where air quality is below national levels already may be subject to stricter emission-reduction levels as dictated by local air quality review boards. These areas, known as non-attainment zones, may require hospitals to deploy the best available controls technology for diesel emissions — and operators need to be especially aware of the penalties for violating these regional standards.

In other areas where power grid capacity creates high demand, these emission solutions increase the efficiency and return on emergency system capital investment by allowing standby system use during periods of peak demand when utility rates are higher.

EPA's evolution

Since the inception of the Clean Air Act in 1970, the EPA has sought to reduce harmful nitrogen oxides (NOx), particulate matter (PM), carbon monoxide and hydrocarbon emissions produced by diesel-powered engines. With regard to high-horsepower stationary diesel engines, the EPA's Tier 4 clean air initiative is being implemented in two phases. The current

Tier 4I regulation that went into effect on Jan. 1, 2011, was the first step toward implementing the Tier 4 Final (Tier 4F) regulations that become effective on
Jan. 1, 2015.

Tier 4I mandated significant reductions of NOx and PM exhaust emissions, and Tier 4F will restrict emissions even further for high-horsepower generator sets (see table, Page 46).

To help mission-critical industries achieve Tier 4I certification, some generator manufacturers began offering Tier 4I generator sets in advance of the 2011 effective date. Similarly, a few manufacturers have performed the necessary testing to obtain Tier 4F certification as soon as the EPA initiates the approval process in January 2014, one year prior to its effective date in January 2015.

These generators, which already meet all Tier 4F standards, are referred to as "Tier 4-capable."

Nonemergency scenarios

While hospitals are perhaps the most qualified to operate in backup power mode for emergency purposes, administrators who seek to produce power for nonemergency applications in new facilities or with new backup power systems must install Tier 4-certified generator sets or be prepared to pay the fines.

Only Tier 4 certification enables hospitals the flexibility to operate for the following nonemergency applications:

Storm avoidance or abatement. The practice of storm avoidance gives hospitals the opportunity to stabilize power in anticipation of utility power disruptions due to incoming storms. In addition, the operator also may elect to self-generate power after utility power has been restored to allow time for a return to normal, stabilized utility power supply.

Prime power. Prime power refers to the option of hospital operators to self-generate power to maintain uptime, improve reliability or augment utility power as needed. One example would be to self-generate power during anticipated periods of high demand to ensure reliability.

Peak shaving or rate curtailment. Peak shaving is a process through which hospitals can participate in an arrangement with local power utilities to self-generate power during the utility's peak demand periods and avoid incurring peak utility rates. This practice is more common in regions of the country where utility rates are well above the national average.

The EPA law requires documentation for all run-time usage including exercising and emergency operation as well as nonemergency usage. According to the Tier 4 regulation, generator sets built after Jan. 1, 2011, must be Tier 4I-certified to enable unlimited nonemergency operation.

For all generator sets that are not Tier 4I-certified, the EPA permits a combined 100 hours per year of exercising, maintenance and nonemergency operation during times when the utility is available. Hospital administrators who are planning new facility construction or replacement of an existing backup power system must anticipate their annual runtime usage and plan accordingly.

Compliance drivers

There are several regions throughout the United States where a combination of high-population density, natural air circulation patterns and subsequent pollution reduces air quality levels well below the EPA's current air quality standards.

For example, much of California has been designated a non-attainment area. Governed by state, local and independent environmental regulatory bodies, these regions enforce more stringent emission requirements than the EPA's national standards.

Depending on the regional requirements and legislation, Tier 4I certification may be required to comply with these more stringent regulations, and even may be mandated to some degree for both emergency and nonemergency applications. Some air quality initiatives could mandate the use of Tier 4-capable generators because they represent the best available control technology for providing the maximum emission reductions. Even local air quality boards have the authority to enforce compliance and level EPA fines.

At the state level, California has instituted the California Air Resource Board and established many individual air quality management districts under its umbrella. The Cap-and-Trade program in California, which took effect in January 2013, is a law that grants permission to operate noncompliant generators in exchange for fines commensurate with the extent of the operator's carbon footprint.

This level of regional regulatory specificity is taking place in such other areas as New Jersey and the Atlanta metropolitan area of Georgia — two of the many regions where non-attainment areas have been established. It stands to reason that additional cities and states throughout the United States will be enforcing non-attainment standards as regulations increase.

Compliance checklist

Health facilities professionals must carefully consider the decision to move to Tier 4I- or Tier 4F-certified generator sets.

Answering the following questions can help to guide the decision-making process.

  • Are the hospital staff planning to install a new backup power system for a new or existing facility?
  • Do the hospital staff plan on self-generating power for purposes other than emergency backup power?
  • Is the hospital located in a non-attainment region that is subject to emission-reduction requirements stricter than the national EPA standards?
  • Do the hospital staff seek to deploy the best available control technology regardless of the regulatory conditions?

If a health facilities professional answers "yes" to the first two questions, he or she will need to upgrade to Tier 4-certified generators for the new, non-emergency-enabled backup power system. If a facilities professional answers "yes" to the third question, he or she should check local regulations and determine whether Tier 4I- or Tier 4F-capable emission reduction is required. If a facilities professional answered "yes" to the fourth question, he or she should choose a Tier 4F-capable generator set to deploy the best available emission control.

Multiple choices

While Tier 2 emission generator sets are acceptable for unlimited emergency use, generators manufactured after Jan. 1, 2011, used beyond the allowable 100 hours in nonemergency situations must be Tier 4I-certified and must be labeled as such.

Some generator manufacturers already are offering a wide range of Tier 4I-certified generators and a few have generator sets that are tested and ready for Tier 4F as soon as the EPA begins the certification process in January 2014.

To ensure that any new power generation systems are completely compliant under the latest regulations, a hospital's best insurance is to select a manufacturer that offers multiple choices for legally required systems, including both Tier 4I- and Tier 4F-certified generator sets, and can recommend the system that best fits local regulations.

For more information on Tier 4, health facilities professionals can log on to

George Williams is eastern regional manager and Terry Seger is central regional manager for Cummins Power Generation, Minneapolis. They can be reached at and, respectively.

Sidebar - Compliance to become common

When new hospitals are making a long-term investment in a power system, facilities professionals should consider how to prepare for the future and be ecologically responsible by installing the best available technology for emission reduction. As responsible standard bearers, hospitals are more likely to achieve Tier 4 compliance sooner than other mission-critical industries.

From the International Building Code (IBC) requirements to various Environmental Protection Agency (EPA) procedures, there are considerable regulations that hospitals need to consider when they're expanding and applying for new construction permits — the EPA's Tier 4 emission regulation is more frequently among them.

The trend is toward increasing regulations and stiffer penalties for offenders. Health facilities professionals who are operating outside of compliance will have to project what their long-term cost will be and decide how to address the problem within the context of their budgetary constraints.

The year 2015 marks the release of the latest IBC requirements and implementation of the Tier 4 Final (Tier 4F) regulation.

While engine manufacturers cannot receive Tier 4F certification until Jan. 1, 2014, for stationary engines used in generator sets, installing Tier 4 interim (Tier 4I)-certified generators today or preordering Tier 4F- or Tier 4I-certified generators for 2014 ensures EPA compliance for the foreseeable future.

Moreover, licensing approval may be a lot easier when a Tier 4-certified generator set is specified in the construction documents.