Alberta Stack Sampling Code for Industrial Facilities

A failed emissions test is rarely caused by the final laboratory result alone. More often, the problem begins with an incomplete test plan, an unsuitable sampling location, missed operating data, or field documentation that cannot support the reported number. The Alberta Stack Sampling Code provides the technical framework for producing emissions data that regulators, permit reviewers, and facility decision-makers can rely on.

For Alberta industrial facilities, stack sampling should be treated as a controlled compliance activity rather than a field exercise performed at the end of a project. The applicable code, approval conditions, and referenced test methods must be considered together. A test that follows a recognized method but does not meet the facility's authorization requirements may still create a compliance issue.

What the Alberta Stack Sampling Code Governs

The Alberta Stack Sampling Code sets expectations for how source-emissions testing is planned, conducted, documented, and reported. Its purpose is to reduce uncertainty in measured emissions by establishing consistent technical practices for representative sampling and quality assurance.

In practical terms, the code affects decisions made before a test crew arrives on site. These include the suitability of the stack test location, access and safety provisions, sampling port configuration, traverse requirements, process operating conditions, instrument calibration, sample handling, and reporting content. It also establishes the need to demonstrate that results represent normal or otherwise specified operating conditions.

The code should not be read in isolation. Facility approvals, Environmental Protection and Enhancement Act requirements, sector-specific obligations, and applicable federal programs can introduce additional parameters, averaging periods, methods, or reporting rules. For example, a source test supporting an approval condition may have different operational requirements than testing performed for an NPRI calculation, greenhouse gas inventory, or equipment performance investigation.

Start With a Test Plan, Not a Mobilization Date

A defensible program begins with a written test plan that is reviewed against the facility's current approval and the required sampling methods. This is where avoidable field delays and unusable data are prevented.

A complete plan should define:

• the emission sources, pollutants, test methods, and required number of runs;

• the required production rate, fuel, control-device status, and other operating conditions during testing;

• sampling location dimensions, ports, platforms, utilities, and safe access requirements;

• field quality control, calibration checks, sample custody, laboratory analysis, and reporting deliverables.

Sampling location is particularly significant. Flow disturbances, insufficient straight duct runs, inaccessible ports, leakage, or unsafe platforms can compromise representativeness or prevent testing altogether. When a location does not meet the preferred criteria, the testing team may need to document the limitation, apply the method's alternative provisions where allowed, and assess the impact on data quality. That determination should be made before mobilization, not after the test window has closed.

Representative Conditions Are a Compliance Requirement

A stack test result has limited value if the process was not operating in a condition that reflects the requirement being evaluated. The test team and facility operations group should agree in advance on the operating envelope that will apply during each run.

For combustion sources, this may include fuel type and heating value, firing rate, excess air, oxygen or carbon dioxide, load, control equipment operation, and process throughput. For manufacturing sources, relevant variables may include feed rate, moisture, production mode, capture-system configuration, or control-device pressure drop and temperature.

Operating data must be recorded at a frequency sufficient to show stability throughout the test. A single control-room reading at the beginning and end of a run may not demonstrate representative operation where loads or control parameters fluctuate. Conversely, testing at maximum production is not automatically required unless the approval, permit, or test objective specifies it. The governing condition should be established in writing.

Field QA/QC Determines Whether Results Are Defensible

The Alberta Stack Sampling Code places strong emphasis on quality assurance because emissions values are only as reliable as the measurements behind them. Field teams must verify instrument performance, sampling train integrity, gas-meter and temperature measurements, and the conditions required by the selected method.

For common gaseous emissions work, this can include analyzer zero and span checks, calibration error evaluations, system bias checks, drift assessments, and documentation of diluent gas measurements. For particulate, metals, acid gases, or other manual sampling programs, leak checks, nozzle selection, isokinetic sampling criteria where applicable, reagent preparation, recovery procedures, and sample custody become central controls.

A valid-looking number should not be substituted for a valid test. If a required quality-control criterion is missed, the appropriate response may be corrective action, an additional run, qualification of the data, or retesting. The right path depends on the method, the magnitude of the deviation, and the intended regulatory use of the result.

Reporting Must Connect the Data to the Requirement

The final report should allow a technical reviewer to understand what was tested, how it was tested, whether the source operated as required, and how reported concentrations or mass rates were calculated. Raw field records, calibration information, laboratory results, operating data, calculations, deviations, and method-specific quality-control results should support the reported conclusions.

Units and reference conditions deserve close attention. Results may need to be expressed on a dry basis, corrected to a specified oxygen concentration, normalized to standard conditions, or converted to mass emission rates. A calculation can be mathematically correct yet unsuitable for compliance comparison if it uses the wrong reference basis.

Before approving a stack test, facility teams should confirm that the reported basis matches the approval limit and that all requested parameters are included. This review is especially valuable when test data will be used for compliance reporting, permit applications, emissions inventories, or capital decisions.

Make the Code Part of Ongoing Emissions Management

The strongest stack sampling programs use each test to improve the next one. Test reports can reveal recurring access constraints, unstable process conditions, calibration issues, control-device performance concerns, or data gaps that should be addressed before the next compliance deadline.

For facilities operating in Alberta, early coordination between operations, EHS personnel, engineering, and qualified testing personnel is the practical way to meet Alberta Stack Sampling Code expectations while protecting safety, production, and the defensibility of the final emissions data.