Most conventional PF's (Pressuriser / Filter) units only address the External Air supply and leave the Recirculation Air supply to be filtered via an internal / integral or separate Filter Panel built into the HVAC. In addition the Filter media used will not maximise protection of the Operators Health and therefore also not meeting legislated Compliance.
Subsequently it is important that any Quality Cabin Environmental Air System address bot the incoming External Fresh Air and also the Recirculation Air Supply within the Cabin- and rapidly remove the Airborne Contamination at filter the air at a suggested rate >20-30 / hour Volume of Cabin.
A Quality Cabin Environmental System must address both the External Air and Recirculation Air supply so as optimise / maximise the Filtration of the Particulate Outside and Inside the Cabin.
1. External Air Supply: The function of the External Air supply is primarily to provide:
2. Recirculation Air Supply: The function of the Recirculation Air supply is primarily to provide:
3. Combination of the Air Supply: The combined objectives for both the External Air and Internal Air PFP's are:
Airborne Particulate and Fibre will enter / become entrapped inside the Cabin from opening of doors / windows, Operator clothing, boots, etc. It is also agitate by movement of the Operator and / or the Machine.
So the Quality Cabin Environmental System must not only remove this contamination from the within the Cabin but also rapidly so as to limit the exposure to the Operator.