What is EPA Method 21?

According to information compiled by the Environmental Protection Agency (EPA), the agency has “found significant and widespread noncompliance with Leak Detection and Repair.” As a matter of fact, in 1999, the EPA estimated that a staggering 40,000 tons of volatile organic compounds (VOCs) are emitted annually – and that’s just from compromised valves stationed at the nation’s petroleum plants.

Because compliance became such a pressing issue, the EPA established yet another, more stringent program that better illustrates its need for LDAR abidance.

A Definition of EPA Method 21

EPA Method 21 is defined by the agency as being “a determination of volatile chemical compound leaks.” It is a method that is used by certified inspectors to best identify possible VOC leaks on process equipment sources. Depending on the nature of the operation, these equipment sources might include “valves, flanges, and other connections, pumps, and compressors, pressure relief devices, process drains, open-ended valves, pump and compressor seal system degassing vents, accumulator vessel vents, agitator seals, and access door seals.”

Generally, this method is not meant to be used as a gauge for a measure of mass emission rate, but rather leak detection, specifically.

Common Leak Sources

Screenshot via EPA.gov

As stated in Section 6.0 of the EPA’s Method 21 document, suspected leaks must be tested with Method 21 by employing a specialized VOC monitoring instrument. Subsequently, samples must be collected, preserved, stored, and transported according to the guidelines.

EPA Method 21 Best Practices

Since the EPA established Method 21 as a response to rampant LDAR noncompliance, it should come as no surprise that the agency has outlined a strict best practices code for managers and inspectors to follow. Included in it are these important points:

  • Safety – Because testing can exacerbate leaks and/or weak spots in equipment sources, it’s imperative that whoever might be testing, whether it’s an in-house associate or a certified Method 21 inspector, must follow appropriate safety protocols. Remember, when left exposed nearly all of these VOCs are damaging to tissue and carry significant fire hazards. The EPA recommends referring to the practices outlined in the  Handbook of Hazardous Materials: Fire, Safety, Health. Alliance of American Insurers to develop a safety plan that is customized to the equipment and hazardous material pairing.
  • VOC Monitoring Instrument – As briefly illustrated above, part of carefully following Method 21 means employing a specialized VOC monitoring instrument and/or process. This detector might vary depending on the specifics of the operation, but the most common types include catalytic oxidation, flame ionization, infrared absorption, and photoionization. In addition to the category of instrument, it must also be capable of displaying an instrument meter scale which shall be readable ±2.5 percent of the specified leak detection concentration. For more information on the VOC monitoring instrument, read Section 6.0 of the EPA’s Method 21 document.
  • Component Identification – Simply monitoring for leaks isn’t enough to be on the right side of the EPA’s compliance guidelines; the agency also requires operations to identify all relevant components that are subject to this specialized testing. This means that every part must have: 1) a unique location and 2) a unique number attached to it. This step is necessary for tracking purposes and may require visual illustrations such as diagrams or other graphics. For heavy-duty tags, consider Camcode’s LDAR tags that are specifically designed for LDAR program compliance.
  • Monitoring Schedule – Contingent on the specific equipment used in the operation, an in-house monitoring schedule must be developed. The EPA requires each facility to keep a detailed register which illustrates relevant readings recorded from the portable VOC monitoring instrument.

Challenges Associated with EPA Method 21 Compliance

Well-Trained LDAR Team

Screenshot via EPA.gov

In the EPA’s LDAR Guide, the agency outlines some of the most common ways in which operations might succumb to noncompliance pitfalls. Listed at the top is the failure to identify “all regular components/units in inventory.” This is a particularly important point to consider for businesses that might be operating out of a large facility that regularly changes its infrastructure or those who have procured a facility that might have been mismanaged in the past. If all relevant components are not identified and regulated as stipulated in Method 21, the facility is likely to suffer a costly and potentially dangerous leak.

In addition to component identification, the EPA also states that, all too often, operations improperly place units on the “Delay of Repair List.” This list should be used only when the component is “technically infeasible to repair without a process unit shutdown.” Ostensibly, the “Delay of Repair List” is a tool that should be used as a last resort, and a temporary one at that. This means that all components, even those located in relatively concealed locations, must be simple to service and monitor on the stipulated maintenance schedule.

Companies that follow best practices and implement personalized LDAR programs are best-equipped to achieve and maintain Method 21 compliance.