Question to the Department for Environment, Food and Rural Affairs:

To ask the Secretary of State for Environment, Food and Rural Affairs, pursuant to the Answer of 19 April 2018 to Question 135379, for what reasons that answer states that there is no commercially available equipment for continuous monitoring of PM10 and PM 2.5 when in an assessment of PM10 and PM2.5 emissions from five energy-from-waste plants by Ricardo AEA Consultancy carried out for his Department and published on 6 January 2016 there is reference to both periodic and continuous emission measurements.

The only reference to continuous measurement in the report is in Section 6 on page 14 which states “….periodic and continuous emission measurements undertaken for regulatory compliance indicated total PM emissions generally below 1 mg/m3 for these facilities….” which is clearly referring to measurement of total particulate emissions, rather than measurement of PM10 or PM2.5. The method by which PM10 and PM2.5 concentrations were measured is set out in section 3.1 of the report. This describes a type of periodic emissions measurement where particles from the exhaust gases are collected onto a material which is weighed in a laboratory before and after the sampling procedure in order to determine the mass of PM10 or PM2.5 collected. The results of this (together with the measurement of the exhaust gas flow rate recorded during the sampling period) are then used to calculate the concentration of these particles in the exhaust gases.