By workplace & process
Fermentation gives off carbon dioxide that is invisible, pools at low level and can asphyxiate, while filtration powder and cleaning chemicals need genuine LEV. The two duties get confused - so this guide separates them.
The short answer
Brewing and distilling raise two different air hazards that are often lumped together. Fermentation gives off carbon dioxide - invisible, heavier than air, and able to pool where people work - while filtration powder, grain dust and cleaning chemicals are the things local exhaust ventilation actually captures. A CO2 monitor does not discharge the LEV duty, and an LEV test does not discharge the CO2 duty, so it helps to keep them apart.
The detail
Carbon dioxide has a workplace exposure limit of 5,000 parts per million as an eight-hour average and 15,000 parts per million over fifteen minutes. It is colourless, odourless and denser than air, so it collects in cellars, tanks, vessels and pits with little warning, and higher concentrations can cause headaches, unconsciousness and death. Controlling it is mainly a matter of gas detection, general and dilution ventilation, and confined-space precautions for entering vessels - not capture-at-source LEV.
The genuine LEV point sources sit elsewhere. Kieselguhr, or diatomaceous earth, used for filtration contains respirable crystalline silica, so handling it needs proper dust capture; malt and grist dust at intake and milling needs the same; and vapour from caustic or acid cleaning-in-place needs local capture. Distilling adds ethanol vapour and heat. These are where local exhaust ventilation belongs and where its performance has to be proven. It is worth holding these apart from the carbon dioxide question, because the controls look nothing alike - a dust extract over a filtration station on one hand, a fixed gas monitor and forced ventilation in a cellar on the other - and a site that has fitted one can wrongly assume it is covered for the other.
What it means for you
A thorough examination and test of brewery and distillery LEV confirms that capture at the filtration station, the grist and malt handling and the cleaning points is holding the dust and vapour and moving air at the commissioned rate. The silica in kieselguhr means the filtration extraction in particular has to be effective, and the examiner checks it against the design at least every fourteen months with user checks between.
The value of separating the duties is that neither gets neglected. The CO2 hazard is managed through detection and ventilation, and the dust and vapour hazards through tested LEV. Treating them as one control leaves a gap - proving the LEV performs, distinct from your gas-detection arrangements, is what closes it.
The service behind the guide
We test brewery and distillery LEV at filtration, grist handling and cleaning, and help you distinguish that from the CO2 detection and ventilation duty, with a clear report.
Questions
Not really. Carbon dioxide from fermentation is colourless, odourless and heavier than air, so it pools in cellars, vessels and pits. That is a gas-detection, ventilation and confined-space duty rather than a job for capture-at-source LEV.
Carbon dioxide has a workplace exposure limit of 5,000 parts per million as an eight-hour average and 15,000 parts per million over fifteen minutes. Higher concentrations can cause headaches, unconsciousness and death with little warning.
At real point sources: kieselguhr or diatomaceous-earth filtration powder, which contains respirable silica; malt and grist dust at intake and milling; and vapour from caustic or acid cleaning. Distilling adds ethanol vapour and heat.
Because a CO2 monitor does not discharge the LEV duty, and an LEV test does not discharge the CO2 duty. Treating them as one control leaves a gap. Each hazard needs its own, correctly tested control.
At least every fourteen months under COSHH, with user checks between. The test confirms the filtration, grist and cleaning capture is performing - separately from your gas-detection arrangements.
Phoenix Duct Clean · by the numbers
We test brewery and distillery LEV at filtration, grist handling and cleaning, and help you distinguish that from the CO2 detection and ventilation duty, with a clear report.