This paper reviews the application of the new RM20H Special Analytes Smoking Machine, which incorporates a flexible trapping arrangement into the standard rotary RM20 smoking system to support the range of mainstream traps that are required by the Hoffmann analysis list. To create a versatile and chemically safe 'operational' space whilst providing good access for operators the RM20H has a compartmentalised smoke trap area designed to accommodate standard filter pad traps, XAD-4, electrostatic and multi-stage impinger trapping systems and cooling baths etc. This RM20H configuration also supports mainstream gas phase analysis. To facilitate greater access for operators and trapping apparatus the smoke hood top cover is modified to incorporate a hinged arrangement that seals the front of the machine when the hood is lowered.