NPL organises three proficiency testing (PT) schemes in the stack emissions measurement area: Particulate, Gas Measurement and Calibration Gas. The Particulate scheme is run annually with test items sent to participants. The Gas Measurement and Calibration Gas schemes are run bi-annually with measurements conducted at NPL.

• The aim of the Particulate stack emissions proficiency testing scheme is to assess performance with the weighing of foil shims and simulated particulate test probe wash. Foil shims are provided with known masses traceable to national standards. The standard deviation for proficiency testing is set from consideration of previous round results and with due consideration to relevant directives and standards. Foil shims and simulated probe washes are sent to participants.
  
  

• The aim of the Calibration Gas Proficiency testing scheme is to assess the performance of test houses with the measurement of test gases from NPL certified cylinders. These measurements are conducted at the National Physical Laboratory. The scheme involves the measurement of combustion gases (NOx, SO₂, CO, O₂ and VOCs) at concentrations and conditions typical of plant falling under the Waste Incineration Directive (WID) and Large Combustion Plant Directive (LCPD).
  
  

• The Gas Measurement PT scheme is conducted at the stack simulator facility located at the National Physical Laboratory. The scheme involves the measurement of combustion gases (NOx, SO₂, CO, O₂ and VOCs) at concentrations and conditions typical of plant falling under the Waste Incineration Directive (WID) and Large Combustion Plant Directive (LCPD). The aim of the scheme is to test a complete continuous emissions measurement system from sampling probe to analyzer.

For further information and registration details, please visit our dedicated Stack PT Schemes website.