Continuous Emission Monitoring (CEMS)

• USEPA Performance Specification 11 (PS-11)
• USEPA Quality Assurance Procedure 2 (Proc 2)
• WA CEMS Code
• NSW EPA CEM-11

• USEPA Performance Specification 1 (PS-1)
• USEPA Quality Assurance Procedure 3 (Proc 3)
• WA CEMS Code
• NSW EPA CEM-1

• USEPA Performance Specification 2 (PS-2)
• USEPA Quality Assurance Procedure 1 (Proc 1)
• WA CEMS Code
• NSW EPA CEM-2

• USEPA Performance Specification 3 (PS-3)
• USEPA Quality Assurance Procedure 1 (Proc 1)
• ISO 12039 Stationary source emissions — Determination of the mass concentration of carbon monoxide, carbon dioxide and oxygen in flue gas — Performance characteristics of automated measuring systems
• WA CEMS Code
• NSW EPA CEM-3

• USEPA Performance Specification 4 (PS-4)
• USEPA Performance Specification 4A (PS-4A)
• USEPA Quality Assurance Procedure 1 (Proc 1)
• WA CEMS Code
• NSW EPA CEM-4

• AS 4323.4 – Stationary source emissions – Area source sampling – Flux
  chamber technique
• NSW EPA OM-8 – Odour sampling from diffuse sources

• USEPA Performance Specification 6 (PS-6)
• USEPA Quality Assurance Procedure 1 (Proc 1)
• WA CEMS Code
• NSW EPA CEM-6

• USEPA Performance Specification 7 (PS-7)
• USEPA Quality Assurance Procedure 1 (Proc 1)
• WA CEMS Code
• NSW EPA CEM-7

• USEPA Performance Specification 8 (PS-8)
• USEPA Performance Specification 8A (PS-8A)
• USEPA Performance Specification 9 (PS-9)
• USEPA Performance Specification 15 (PS-15)
• USEPA Quality Assurance Procedure 1 (Proc 1)
• NSW EPA CEM-8
• NSW EPA CEM-9
• NSW EPA CEM-10

• USEPA Performance Specification 12A (PS-12A)
• USEPA Performance Specification 12B (PS-12B)
• USEPA Quality Assurance Procedure 5 (Proc 5)
• NSW EPA CEM-12

• USEPA Performance Specification 16 (PS-16)
• USEPA Quality Assurance Procedure 1 (Proc 1)

• USEPA Performance Specification 18 (PS-18)
• USEPA Quality Assurance Procedure 6 (Proc 6)
• NSW EPA CEM-13

• USEPA Performance Specification 19 (PS-19)
• USEPA Quality Assurance Procedure 1 (Proc 1)

• Ammonia (NH3)
• Moisture (H2O)
• Nitrous Oxide (N2O)
• Hydrogen Fluoride (HF)

A Continuous Emissions Monitoring System (CEMS) is a system used to continuously measure and record selected emissions from an industrial source. Depending on the application, a CEMS can monitor pollutants and parameters such as NOx, SO₂, CO, CO₂ O₂ and more. CEMS data can support emissions management, regulatory monitoring and environmental compliance reporting.

A CEMS may be required where an environmental licence, regulatory requirement, or project-specific condition specifies continuous emissions monitoring. Whether a CEMS is necessary depends on the facility, emission source, pollutants, operating conditions, and applicable Australian regulatory requirements. The relevant environmental licence and regulatory conditions should be reviewed before selecting a monitoring approach.

CEMS provides continuous or near-continuous measurement of specified emissions, allowing emissions trends and changes to be monitored over time. Manual stack testing involves periodic sampling and measurement during defined testing runs. The two approaches serve different purposes and may be used together where required for compliance, validation, or performance assessment.

Yes. Ektimo provides CEMS services covering activities such as system design, installation, commissioning, validation, and ongoing support. The appropriate system configuration depends on the pollutants, process conditions, environmental licence requirements, applicable performance standards, and site-specific requirements.

CEMS accuracy can be assessed using appropriate performance testing and comparison procedures specified by the applicable Australian regulatory requirements or performance standards. Depending on the system and jurisdiction, this may involve calibration, relative accuracy testing, quality-assurance procedures, and comparison with reference measurements.

CEMS commissioning requirements depend on the applicable regulatory requirements, system configuration, and performance standards. Testing may include calibration, analyser checks, system verification, performance testing, and comparison against reference methods. The required commissioning and validation activities should be established from the relevant environmental licence, regulatory requirements and applicable standards before the system is placed into compliance service.

Inaccurate CEMS readings can be investigated by reviewing calibration records, service, maintenance logs, analyser performance, sampling systems, operating conditions, data trends, and comparison measurements. Potential causes can include instrument drift, sampling-system problems, calibration issues, or changes in process conditions. A structured investigation can help identify the source of the discrepancy and determine appropriate corrective action.

CEMS inspection, calibration, validation, and audit frequency depends on the applicable Australian regulatory requirements, environmental licence, performance standards, system design and manufacturer’s recommendation. Some systems require scheduled quality-assurance activities and periodic performance testing. The monitoring program should therefore be based on the specific requirements applying to the facility rather than a universal testing interval.