Preparing for Your Upcoming Stack Test

Source Emissions testing, or stack testing, is mandated by the Clean Air Act of the U.S. Environmental Protection Agency (EPA), which sets forth guidelines and requirements that must be met to determine a facility’s compliance with emission limits.  Any and all plants, factories, and facilities that utilize a stack as part of manufacturing or production operations are required to undergo stack testing in order to demonstrate compliance with current EPA standards.  There is more to stack testing than simple compliance, however.  A properly-executed testing plan gives you the diagnostic tools to help optimize your operations and improve energy efficiency — quality incentives for voluntary stack testing that is not simply driven by EPA requirements.  With careful preparation for stack-testing compliance and the proper execution of the test plan, a company can save money, protect workers, and effectively streamline their operations.

As a company prepares their facility for an upcoming stack test, reviewing the state-approved test plan is the best way to ensure that you understand all of the testing requirements.  Doing so is your greatest insurance that the stack testing results will show proper compliance with all relevant EPA air emission standards.  However, in many cases technical or legal jargon may make a portion or the entirety of the test plan difficult to understand, and it may not contain all of the required information necessary to conduct a successful test.  To assist you with this, we have put together the following Stack Testing Preparation Checklist to help you make sure that your company is properly prepared for your upcoming testing.  All items on this checklist should be reviewed with your qualified stack-testing team.

  1. What Load you will test at – This information is typically in your air permit, and/or determined by applicable federal/state  regulations.
  2. What Fuel you will burn – Different fuel types can have vastly different emission limits
  3. OSHA compliant platforms – How will the stack test team reach the sampling plane?
  4. Power Requirements – Do you have enough circuits?
  5. Safety/Insurance Concerns- What are your facility requirements?  Does your stack test company meet these requirements?
  6. Are your Test Ports free from blockage and EPA Method 1 Compliant?
  7. What Process Data are you required to document, and how will that data be logged?

Here at Environmental Source Samplers Inc., we’re familiar with the pitfalls a company can experience when faced with an upcoming test.  Advance preparation, with these guidelines in mind, will provide your company the ability to address any issues or questions prior to the stack testing date. Saving your company the time, hassle, and money that late revisions and changes inevitably cause.  These guidelines are also helpful in maintaining high levels of safety and compliance regardless of having a scheduled stack test or not, benefitting the overall operations and their environmental impact.

Choosing a stack testing company that has the appropriate background and experience for your industry will help ensure that your stack test will be successful.  The stack testing company should have the capability to execute the testing types and methodologies that govern your specific operations, while using equipment that is well-maintained and up-to-date.  Just as importantly, they should be current and informed on the changes and revisions to existing testing methodologies, since the EPA air emission limits and standards are subject to change as the Agency sees fit.

Stack testing is required and performed for the health and safety of the plant, the workers, and the environment.   It is also a diagnostic tool that provides insight into the efficiency of your operations.  However, whether you are testing for compliance or diagnostic purposes, careful preparation is the key to ensuring that your stack testing project gives you the data that you can use effectively.

Please contact the experts at Environmental Source Samplers (ESS) to learn more about their stack testing services:

Phone: 910-799-1055
Email: [email protected]

Three Decades of Condensable Particulate Matter (CPM) Regulation

2017-03-17 Three Decades of CPM Regulation


Condensable Particulate Matter (CPM) is material that is in a vapor state at stack conditions, but condenses and/or reacts upon cooling and dilution in the ambient air to become solid or liquid Particulate Matter (PM) immediately after discharging from the stack.  All CPM is assumed to be in the PM2.5 size fraction.


1987  After promulgating the PM10 National Ambient Air Quality Standards (NAAQS) the EPA began recommending that, in certain circumstances, states consider including the condensable portion of PM10 emissions in the determination of total and fine PM emissions from major stationary sources.

1991  EPA Promulgated Method 202.  The original Method used wet impingers – in which sulfur dioxide was captured and formed sulfur trioxide and sulfuric acid artifacts. This caused captures to be biased high by improperly quantifying the sulfuric artifacts as condensable PM.

[Read more…]

EPA News: EPA Report Shows Air Emissions of Toxic Chemicals from Industrial Facilities Down More Than Half Since 2005

2017-01-13 Toxic Air Emissions Down 56 Percent

WASHINGTON — The U.S. Environmental Protection Agency today released its annual Toxics Release Inventory (TRI) National Analysis, which shows releases of toxic chemicals into the air fell 56% from 2005-2015 at industrial facilities submitting data to the TRI program.

“Today’s report shows action by EPA, state and tribal regulators and the regulated community has helped dramatically lower toxic air emissions over the past 10 years,” said Jim Jones, EPA Assistant Administrator for the Office of Chemical Safety and Pollution Prevention. “The TRI report provides citizens access to information about what toxic chemicals are being released in their neighborhoods and what companies are doing to prevent pollution.”

The report shows an 8% decrease from 2014 to 2015 at facilities reporting to the program contributed to this ten-year decline. Hydrochloric acid, sulfuric acid, toluene and mercury were among chemicals with significantly lower air releases at TRI-covered facilities. Medical professionals have associated these toxic air pollutants with health effects that include damage to developing nervous systems and respiratory irritation.

[Read more…]

OSHA News: US Department of Labor Issues Final Rule to Lower Beryllium Levels

2017-01-06 New OSHA Rule for Beryllium Exposure

WASHINGTON – A new rule issued today by the U.S. Department of Labor’s Occupational Safety and Health Administration dramatically lowers workplace exposure to beryllium, a strategically important material that can cause devastating lung diseases. The new beryllium standards for general industry, construction and shipyards will require employers to take additional, practical measures to protect an estimated 62,000 workers from these serious risks.

Beryllium is a strong, lightweight metal used in the aerospace, electronics, energy, telecommunication, medical and defense industries. However, it is highly toxic when beryllium-containing materials are processed in a way that releases airborne beryllium dust, fume, or mist into the workplace air that can be then inhaled by workers, potentially damaging their lungs.

Recent scientific evidence shows that low-level exposures to beryllium can cause serious lung disease. The new rule revises previous beryllium permissible exposure limits, which were based on decades-old studies.

[Read more…]

EPA News: EPA Names First Chemicals for Review Under New TSCA Legislation

EPA News: 10 Chemicals Under TSCA Review

WASHINGTON – Today, EPA is announcing the first ten chemicals it will evaluate for potential risks to human health and the environment under TSCA reform.

“Under the new law, we now have the power to require safety reviews of all chemicals in the marketplace.” said Jim Jones, assistant administrator of the of Office of Chemical Safety and Pollution Prevention. “We can ensure the public that we will deliver on the promise to better protect public health and the environment.”

The first ten chemicals to be evaluated are:

  • 1,4-Dioxane
  • 1-Bromopropane
  • Asbestos
  • Carbon Tetrachloride
  • Cyclic Aliphatic Bromide Cluster
  • Methylene Chloride
  • N-methylpyrrolidone
  • Pigment Violet 29
  • Tetrachloroethylene, also known as perchloroethylene
  • Trichloroethylene

Toxic Substances Control Act (TSCA) as amended by the Frank R. Lautenberg Chemical Safety for the 21st Century Act, requires EPA to publish this list by December 19, 2016. These chemicals were drawn from EPA’s 2014 TSCA Work Plan, a list of 90 chemicals selected based on their potential for high hazard and exposure as well as other considerations.

When the list is published in the Federal Register it will trigger a statutory deadline to complete risk evaluations for these chemicals within three years.  This evaluation will determine whether the chemicals present an unreasonable risk to humans and the environment. If it is determined that a chemical presents an unreasonable risk, EPA must mitigate that risk within two years.

Under the newly amended law, EPA must release a scoping document within six months for each chemical. This will include the hazard(s), exposure(s), conditions of use, and the potentially exposed or susceptible subpopulation(s) the agency plans to consider for the evaluation.

Additional chemicals will be designated for evaluation, and all of the remaining Work Plan chemicals will be reviewed for their potential hazard and exposure. For each risk evaluation that EPA completes, TSCA requires that EPA begin another. By the end of 2019, EPA must have at least 20 chemical risk valuations ongoing at any given time.

For more on the chemicals listed and additional information:



Cathy Mibourn

[email protected]



Scientists Find Way to Convert CO2 Into Ethanol

CO2 to Ethanol

Scientists at the Oak Ridge National Laboratory in Tennessee have discovered a chemical reaction to turn CO2 into ethanol, potentially creating a new technology to help avert climate change. Their findings were published in the journal ChemistrySelect.

Researcher had hoped to convert carbon dioxide that had been dissolved in water to methanol, a chemical released naturally by volcanic gases and microbes, which can cause blindness in humans if ingested.

But instead of methanol, they discovered they had ethanol, a primary component of gin and also a potential fuel source. Surprised, the team realized that not only was their new material converting the carbon dioxide to ethanol, it needed very little outside support.

The material is a small chip–about a square centimeter in size–covered in spikes, each just a few atoms across. Each spike is constructed out of nitrogen with a carbon sheath and a small sphere of copper embedded in each tip. The chip is dipped into water and carbon dioxide is bubbled in. The copper acts as a small lightning rod, attracting electricity and driving the first steps of the conversion of the carbon dioxide and water into ethanol, before the molecules move to the carbon sheath to finish the process.

Read more about this exciting development in the full article from Popular Science.

Supreme Court Halts MATS Rule

Late Tuesday it was announced that the U.S. Supreme Court has halted the implementation of the Mercury and Air Toxics (MATS) rule.  This is the first time in recent memory that the U.S. Supreme Court has put a rule on hold before the lower court review.  Rulings from the lower court are expected over the summer.

Here are some other articles discussing the Supreme Court’s decision to put the MATS rule on hold:

Supreme Court To EPA: Fool Me Once

Carbon pollution controls put on hold

Supreme Court Puts White House’s Carbon Pollution Limits On Hold


Sample Port Installation, EPA Method 1, and Successful Testing

Too often the installation of sampling/testing ports is an afterthought in the process of stack construction.  However, sampling ports are essential to the stack testing process which is a requirement for demonstrating compliance.  In fact, the EPA goes so far as to state outright that Method 1 should be taken into consideration before stack construction begins.

Having a better understanding of EPA Method 1 can reduce or eliminate the need for excess modifications on an existing source.  That means knowing the optimum location for sampling ports can save money in your compliance testing budget.

So what is EPA Method 1 exactly and how can it be helpful to the pre-construction design and post-construction installation of sampling ports?

Simply stated, EPA Method 1 is a way to determine sampling port locations that are free from swirling air, or cyclonic flow.

What causes Cyclonic Flow?

Cyclonic Flow occurs when the sampling plane is too close to a disturbance (vane straighteners, fans, control equipment, etc.) or any duct configuration that causes a disturbance in the air flow causing the air to swirl rather than travel on a linear path.

Determining Placement of Sampling Ports

EPA Method 1 provides two options for sample port installation, as follows:

Simplified – Used most often and applies to most stacks

Alternative – Used for smaller stacks with a diameter less than 12 inches

The majority of our clients have larger stacks, so we’ll overview the Simplified Port Installation guidelines, but don’t hesitate to call us at 1-888-363-0039 if you need assistance understanding Alternative Port Installation.

Three Conditions for Simplified Port Installation

  1. The flow through the stack at the port location must be minimally cyclonic.

Following Method 1 procedures as detailed by the EPA prevents issues with cyclonic flow for most stationary sources.  Cyclonic flow at a sampling plane will skew results which becomes an expensive issue if it causes compliance failure, that’s why ESS conducts EPA Method 1 with all stack testing.

  1. The stack diameter must be 12 inches or greater or 113 square inches in a cross-sectional area.

When the stack diameter is less than 12 inches, Alternative Port Installation must be used.

  1. The sampling plane must be located more than two stack diameters from the nearest upstream disturbance and more than half a stack diameter from the stack exit or next downstream disturbance.  (See Diagram 1).

    Diagram 1 Sample Port Placement

A disturbance is anything that interrupts or alters the flow of air and gas through the stack.  Examples of disturbances include: fans, duct bends, stack exits and vane straighteners.

Upstream measurement is the distance between the test ports and the nearest upstream disturbance.

Conversely, downstream measurement is the distance between the test ports and the stack exit.

To calculate the equivalent diameter of a rectangular duct use the equation:
De= 2(LxW) / (L+W)

While those three items cover the requirements for Method 1 Simplified Port Installation, there are still other sampling port factors to consider for a smooth test day.

Port Size and Pollutants Tested

Particulate, metals, dioxin/furans, flowrate or other manual method tests require a minimum of two (2) 4”-diameter ports located 90 degrees from each other.  PM10 and PM2.5 require at least two (2) 6”-inch ports.  It is common to install four (4) of these test ports 90 degrees apart from each other so that more testing can be conducted simultaneously.  The distance of 90 degrees apart is a requirement whether two (2) or four (4) ports are installed.

Sampling ports for gases should be greater than one-quarter-inches in diameter and installed directly above one of the manual method ports.

Port Access

OSHA-compliant platforms are required for the testing team to access the sampling plane safely and effectively.  All installed platforms should be a minimum of 48 inches wide from stack wall to handrail.  If a temporary platform must be erected, then OSHA-compliant scaffolding is preferred, but man lifts are also acceptable.  Scaffolding should be constructed directly in front of each sample port with enough room for the sampling equipment to access the ports (see diagram 2).

Diagram 2 Scaffolding Placement

Diagram 2 Scaffolding Placement

The safety of our crew is of utmost concern, so OSHA-compliant structures are mandatory for testing.

When test day arrives, be sure that sample ports are clean and free from debris.  Sample port condition is regularly monitored by state regulators.

Stack pressure and stack temperature can also affect sampling plane design—call us if you have questions on this point.

There are many issues to consider for an emissions test.  Being prepared with the knowledge to properly construct sample ports will save money by preventing excessive stack modification.  Furthermore, understanding and adhering to the guidelines of EPA Method 1 will ensure that sample port, size, placement, and access are not an issue on test day.

For assistance in determining your specific sampling port needs, questions about EPA Method 1, or any other stack testing issues feel free to call Environmental Source Samplers at 1-888-363-0039.  It would be our pleasure to assist you.

Download a PDF version of this article.

Copyright © 2018 by Environmental Source Samplers, Inc.  All rights reserved.

Understanding Upstream and Downstream

The terms “upstream” and “downstream” are frequently used in the stack testing industry to describe direction within a stack.  However, these terms are often confused and used opposite of their intended meaning.

The key to remembering upstream and downstream when talking about flow is to think about another flowing object—a river!

Rivers generally flow from a source, like a mountain lake, to an outlet, like the ocean where the freshwater disperses into the saltwater.  In terms of stack air flow, the air emissions originate from an emissions source and travel through the stack to the stack exit where they disperse into the atmosphere.

The direction of travel from a source to an outlet is with the current, or downstream.  Conversely, the direction of travel from an outlet to a source is against the current, or upstream.

There are two simple mnemonic devices which can help you to remember the difference between upstream and downstream.

“Up the Creek Without a Paddle”

Imagine you are in a canoe enjoying a peaceful trip down the river when you hear the sound of a waterfall ahead.  You look around for your oars, but there are none in sight.  Frantically, you use your arms to try to paddle further upstream to safety, but it is very difficult because you are fighting the current.  This is a situation of being up the creek without a paddle.

Upstream is the direction toward the source and also against the current.

Upstream Downstream Diagram

Diagram Showing Upstream and Downstream in Relation to Current


“Gently Down the Stream”

Now imagine that you made it safely to the river bank and carried your canoe to bypass the waterfall on foot.  You put the canoe back into the river where you can lay back and relax because the current is carrying you gently down the stream to your destination.

Downstream is the direction away from the source and also with the current.

The diagram above is a visual aid demonstrating the relationship between current and upstream/downstream direction.

If you have questions about this topic, or any other emissions testing question, please call Environmental Source Samplers at 1-888-363-0039 and we will be happy to help you.

Download a PDF version of this article.

Copyright © 2015 by Environmental Source Samplers, Inc.  All rights reserved.

ESS Asia Conducts Isokinetic Training for EATC Students

Hanoi, Vietnam – Environmental Source Samplers, Inc. (ESS) continues its growth in the air-testing and environmental air-consulting markets of Southeast Asia. Continuing its multi-year expansion into the networks of the environmental sector of Vietnam, ESS was awarded a contract to provide training in the conduct of isokinetic emissions sampling for employees of the Vietnamese company Environment Analyze and Technique (EATC). EATC selected four of their most-experience and qualified technicians to attend the ESS training seminar, in order to further expand their skills with Apex Instruments isokinetic sampling equipment.

EATC students in Vietnam 2The objective of the three-day seminar was to introduce the EATC technicians to the basic principles of isokinetic testing and develop their sampling skills. The course was designed to train the students to develop the ability to plan, guide, evaluate, and personally conduct the source-sampling techniques and measurements in order to determine certain pollutant’s emission rates from stationary sources. The course provided a detailed review of EPA Methods 1 through 5, used to measure emission rates of Filterable Particulate Matter (FPM) from emissions sources.

Chief among the skills, methods, and techniques provided by the course was an overview of the basic operations of the sampling equipment, including the nomenclature and terminologies associated with its usage. Also covered were the purpose of the relevant testing methods, and an introduction to the field and lab calibrations and calculations that are a part of the methodology. Finally, ESS hosted a field sampling exercise to demonstrate the conduct of a Method 5 test, utilizing the Apex Instruments Source Sampling Train.

Emissions sampling is an increasingly important aspect of environmental protection in the Asian market, as the environmental impact of increasingly-rapid growth and industrialization are felt in the quality of air and water. As ESS’s work has grown in the Southeast Asian region, it has been increasingly important to maintain a staff and local presence in these growing markets. In January of 2013 ESS opened its first Asian office in Hanoi, Vietnam. In early February, ESS signed an agreement with Berkman Systems, allowing ESS to combine its expertise in US EPA sampling methodologies with the Berkman network of operations in Metro Manila, Cebu, and Davao, Philippines. ESS has leveraged its connections to grow rapidly in the region’s environmental sector, and continues to provide cost-effective solutions, and superior technical support for our client’s consulting and air-testing needs.

ESS is proud of our growing list of clients and network with key Vietnamese environmental firms such as EATC. ESS will continue to maintain its competitive advantage by building on its international experience; developing offices in strategic markets and assuring client satisfaction on every project.

Founded in 1979, ESS has been conducting point source, ambient and industrial hygiene air quality testing and consulting. ESS utilizes modern and consistently maintained equipment to conduct its testing services world-wide. They are qualified to conduct a wide range of air testing methodologies in almost any environment – and for almost any industry. ESS clients have easy access to the reliable and accurate reporting of test results through a secure online client portal, accessible through the main website, The ESS network of reputable vendors and service providers enables us to drive all our projects to on-time and on-budget completion. To learn more about ESS and their air quality testing services in Asia, the U.S. and beyond, please call (910) 799-1055 or visit

Here are a few more photos from the training exercises…

EATC students in Vietnam 3 EATC students in Vietnam 4 EATC students in Vietnam