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LEV testing - batteries and chemicals
Charging batteries and handling chemicals both put invisible hazards into the air - the gas and acid mist from charging, the vapours from chemicals. These are not fringe risks; they are real airborne hazards that extraction is there to control, which makes the LEV, and its testing, something you genuinely cannot skip.
The short answer
Battery charging - particularly of lead-acid batteries - gives off hydrogen gas, which is explosive in concentration, and acid mist that harms the lungs; chemical handling releases vapours that can be toxic or harmful to breathe. These are genuine airborne hazards, and local exhaust ventilation controls them by capturing or removing them at source. Because the hazards are real and the consequences serious, the LEV and its testing are not optional - skipping the extraction, or failing to prove it works, leaves a real explosion or health risk uncontrolled.
Invisible hazards in the air
Both battery charging and chemical handling share a feature that makes them dangerous: they put hazards into the air that you cannot see. Charging batteries and handling chemicals do not look obviously hazardous - there is no flame, no visible cloud - but both release airborne substances that are genuinely harmful, invisibly. That invisibility is exactly what makes them easy to underestimate and important to control: the hazard is there in the air whether or not anyone can see it, and workers breathe it or are exposed to it regardless.
So these are real airborne hazards that need controlling, not fringe concerns. The substances released - the gases and mists of charging, the vapours of chemicals - are exactly the kind of thing local exhaust ventilation exists to control: airborne contaminants that have to be captured or removed before they harm people. Understanding that charging and chemical handling release genuine, if invisible, airborne hazards is the starting point for seeing why the LEV controlling them is something that cannot be skipped. The lack of a visible danger does not mean the absence of one.
Battery charging
Battery charging, particularly of the lead-acid batteries common in industrial and vehicle use, releases two hazards worth naming. The first is hydrogen gas: charging lead-acid batteries gives off hydrogen, and hydrogen is explosive when it accumulates to a sufficient concentration in the air. A charging area where hydrogen builds up is a genuine explosion risk - an invisible, odourless gas reaching an explosive concentration is exactly the kind of hidden hazard that causes serious incidents. The second is acid mist - fine droplets of acid released during charging, which is harmful to breathe and damaging to the airways.
So a battery charging area has both an explosion hazard from hydrogen and a health hazard from acid mist, both airborne, both invisible. This is why charging areas need proper ventilation and extraction - to prevent hydrogen accumulating to an explosive level and to remove the acid mist from the air workers breathe. The extraction controlling a charging area is doing serious safety work on both fronts, addressing a real explosion risk and a real health risk that the ordinary appearance of a battery on charge gives no hint of. It is exactly the kind of hazard that must not be left uncontrolled.
Chemical handling
Chemical handling is the other case, and the hazard there is vapour. Many chemicals used in workplaces - solvents, cleaning agents, process chemicals and countless others - give off vapours that are harmful or toxic to breathe. Handling, mixing, applying or working with such chemicals releases those vapours into the air, where workers can inhale them, with effects ranging from irritation and harm to the respiratory system to more serious toxic effects depending on the chemical. The vapour is often invisible, so again the hazard is in the air without any visible sign.
So chemical handling that releases harmful vapours is a genuine airborne health hazard that has to be controlled - which local exhaust ventilation does by capturing the vapour at source, at the point the chemical is handled, before it reaches the worker's breathing zone. The specific hazard depends on the chemical, but the principle is constant: harmful vapours released into the air need capturing at source, and LEV is the control that does it. A workplace handling chemicals that give off harmful vapours has a real exposure to control, and the extraction is what keeps those vapours out of the air people breathe.
Why you can't skip the LEV or its testing
The reason the LEV for these hazards cannot be skipped comes down to the seriousness of what it controls. An uncontrolled charging area risks a hydrogen explosion and workers breathing acid mist; uncontrolled chemical handling risks workers breathing toxic or harmful vapours. These are not minor exposures but real risks with serious consequences - explosion, respiratory harm, poisoning. Extraction is the control that prevents them, so skipping it leaves those serious hazards uncontrolled, which is a risk no workplace should accept.
And as with any LEV, the extraction only controls the hazard if it is working - so the testing cannot be skipped either. LEV controlling these hazards must be examined and tested, as the law requires for extraction controlling a health hazard, to confirm it is genuinely capturing or removing the gas, mist or vapour it is there to control. An untested system might be failing silently, leaving the explosion or health risk uncontrolled without anyone knowing. So for battery charging and chemical handling, both the LEV and its testing are essential - the extraction controls real, serious airborne hazards, and the testing proves it is actually doing so. Neither is optional where the consequences are this grave.
The takeaway
Battery charging releases hydrogen - explosive in concentration - and acid mist that harms the lungs; chemical handling releases vapours that can be toxic or harmful to breathe. These are genuine airborne hazards, invisible and easy to underestimate, but real and serious. Local exhaust ventilation controls them by capturing or removing them at source, addressing an explosion risk and health risks that the ordinary appearance of a battery on charge or a chemical being handled gives no hint of.
Because the hazards are real and the consequences - explosion, respiratory harm, poisoning - are serious, the LEV and its testing are not optional. Skipping the extraction leaves the hazards uncontrolled; skipping the testing leaves you unable to know whether the extraction is actually working, which for a silently-failing system is the same thing. For battery charging and chemical handling, the extraction is the control you cannot skip, and the testing is the proof you cannot skip either - because invisible hazards with grave consequences demand exactly that certainty.
Questions
Charging lead-acid batteries gives off hydrogen gas, which is explosive when it accumulates to a sufficient concentration, and acid mist - fine droplets of acid that are harmful to breathe and damaging to the airways. Both are airborne and invisible, so easy to underestimate.
Because hydrogen is explosive when it builds up to a sufficient concentration in the air. A charging area where hydrogen accumulates is a genuine explosion risk - an invisible, odourless gas reaching an explosive concentration is exactly the kind of hidden hazard that causes serious incidents.
Vapour. Many workplace chemicals - solvents, cleaning agents, process chemicals - give off vapours that are harmful or toxic to breathe. Handling, mixing or applying them releases the vapour into the air, where workers inhale it, with effects from irritation to serious toxic harm.
By capturing or removing the airborne substance at source - drawing away the hydrogen and acid mist from a charging area, or the vapour at the point a chemical is handled, before it reaches workers. It keeps the gas, mist or vapour out of the air people breathe.
Because it controls real hazards with serious consequences - a hydrogen explosion, acid mist or toxic vapour in the lungs. Skipping the extraction leaves those serious risks uncontrolled, which is a risk no workplace should accept.
Because it only controls the hazard if it is working, and LEV can fail silently. Testing confirms the extraction is genuinely capturing the hydrogen, acid mist or vapour it is there to control. An untested system might be failing, leaving the explosion or health risk uncontrolled without anyone knowing.
We test the extraction controlling battery charging and chemical handling - confirming it genuinely captures the hydrogen, acid mist and vapours at source, so real airborne hazards stay controlled.
