The Health and Safety Executive have published the replacement to MDHS 83/2, MDHS 83/3 in March 2015.
The method covers the measurement of resin acids in Rosin (colophony) solder flux fume.
The original document can be obtained at the link below.
Comply with the COSHH Regulations 
UKAS & MCERTS stack emission monitoring carried out to the highest standard 
Accurately measure your employees' exposures to hazardous substances 
Air Quality Consultancy and Environmental Impact Assessments 
LEV Examination and Testing by P601 Engineers to comply with COSHH Regulation 9