A stack test report tells you what came out of the stack on one day. It does not tell you whether your abatement system is working, whether the result is representative, or whether you will pass the next one. Those are different questions, and they are the ones worth asking.
Got a stack test report you are not sure about? Send it to us with your system details. We will read it against the Clean Air Regulations and tell you what it actually shows.
The Environmental Quality (Clean Air) Regulations 2014 set emission limits by source category and require written approval from DOE before fuel-burning equipment or air pollution control equipment is installed or altered. Approval is granted on a design, and the plant is then expected to demonstrate that it performs as designed.
Two obligations follow. You need approval before you install, and you need monitoring evidence afterwards. Sites that commission equipment and then arrange monitoring as an afterthought usually find the two do not line up.
Removal efficiency claimed by a supplier and removal efficiency measured on your stack are frequently different numbers. On a recent engagement involving an electrophoretic coating line fitted with a UV photocatalytic oxidation system, the third-party test measured across two inlets and one outlet and reported non-methane hydrocarbon removal in the high seventies as a percentage. That figure is only meaningful once you establish three things: whether the sampling captured representative operating conditions, whether the outlet concentration itself sits within the applicable limit regardless of the percentage removed, and whether an upstream fuel-burning source is contributing to what the outlet sees.
Percentage removal is a sales metric. Outlet concentration against the regulatory limit is the compliance metric. They are not interchangeable, and a system can achieve an impressive removal rate and still fail.
We review reports produced by testing laboratories — including reports produced overseas for imported equipment — against Malaysian limits. Common findings: parameters tested that are not the ones DOE will ask about, sampling conducted at a convenient rather than a representative production rate, units or reference oxygen conditions that do not convert cleanly to the Malaysian basis, and missing detail on isokinetic conditions for particulate sampling.
Where continuous emission monitoring is warranted, the specification matters more than the brand. Range, response time, interference from other stack constituents, calibration regime, data logging and how the output will actually be used for compliance reporting all need settling before purchase. We advise on specification independently of any supplier.
For new fuel-burning equipment or new abatement systems, we prepare the DOE submission — source characterisation, expected emissions, control system design basis, predicted performance against the applicable limits, and monitoring arrangements.
| Parameter | Typical source |
|---|---|
| Particulate matter | Boilers, furnaces, dryers, material handling, bag filter outlets |
| Oxides of nitrogen (NOx) | Fuel-burning equipment, thermal oxidisers |
| Sulphur dioxide | Fuel-burning equipment, particularly on heavier fuels |
| Non-methane hydrocarbons and VOC | Coating, painting, printing, solvent handling, e-coat and curing ovens |
| Acid gases | Metal finishing, chemical process scrubber outlets |
| Odour and nuisance complaints | Food processing, rendering, wastewater treatment, composting |
Wet and dry scrubbers, bag filters and cartridge collectors, cyclones, thermal and catalytic oxidisers, activated carbon adsorption, UV photocatalytic oxidation, and biofilters. We assess whether the system chosen is appropriate for the stream, not only whether it is running.