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LEV testing - foundries
A foundry - where metal is melted and cast - is one of the most demanding environments for occupational health. Workers face intense heat, metal fume from molten metal, silica dust from moulding sand, and more, often all at once. Managing these takes a combination of controls working together. Here is how foundries manage heat, fume and metal exposure, in plain terms. This is general information, not a substitute for a proper assessment.
The short answer
Few workplaces concentrate as many serious health hazards as a foundry. Melting metal, pouring it into moulds, and working with the sand those moulds are made from exposes workers to intense heat, metal fume, silica dust and more - often simultaneously. Managing this safely takes a coordinated set of controls. Here's how foundries manage heat, fume and metal exposure, in plain terms. This is general information, not a substitute for a proper assessment. The hazards, all at once. A foundry's work - melting metal in furnaces, pouring molten metal, casting, and making and breaking sand moulds - generates several serious hazards together. Heat: furnaces and molten metal create intense heat, so workers face heat stress (the body struggling to stay cool), which can cause heat exhaustion or worse. Metal fume: when metal is melted and poured, it gives off metal fume - fine metal-oxide particles (the same kind of fume as welding produces). Breathing metal fume can cause metal fume fever (a flu-like illness with fever and aches) and, depending on the metal, other effects - some metals are more toxic than others. Silica dust: the sand used for moulds and cores contains silica, and handling the sand, making moulds, knocking out castings and finishing them releases silica dust - a serious cause of silicosis (an irreversible lung disease) and linked to other lung disease and cancer. Other hazards: gases (from furnaces and processes), other dusts and fumes, noise, and heavy manual handling. So a foundry worker can face heat, fume and dust at the same time - which is what makes the environment so demanding to control. Managing the heat. Heat is managed with a combination of measures: general ventilation to remove hot air and bring in cooler air; cooling and heat shielding (screening workers from radiant heat, cooling systems); sensible work practices (rest breaks, job rotation, pacing work to limit heat exposure); hydration (encouraging drinking to replace fluid lost sweating); and appropriate heat-protective clothing. The aim is to keep workers from overheating despite the hot environment - a matter of both comfort and safety (heat stress can be dangerous). Managing the metal fume. Metal fume is managed mainly with local exhaust ventilation (LEV) to capture the fume at source - over furnaces, at pouring and casting points, and at other fume-generating steps - drawing it away before workers breathe it. Because fume rises on the hot plume of the molten metal, the LEV has to be designed to catch that rising fume. Where LEV can't fully control the fume (some foundry tasks are mobile or awkward to extract from), respiratory protection (RPE) backs it up. The type of metal matters - more toxic metals need tighter control - so the fume control is matched to the metals used. Managing the silica dust. Silica dust is managed by controlling the dust from every dusty step - sand handling and mixing, moulding, knockout (breaking the sand mould off the casting, a very dusty operation), and fettling and finishing. Controls include dust suppression (dampening down), enclosure of dusty processes, local exhaust ventilation to capture the dust at source, good housekeeping (not letting settled dust build up and get re-disturbed - and never dry-sweeping), and RPE. Silica is a serious hazard (silicosis is irreversible), so the dust control has to be effective and sustained. Making the controls work together. The real challenge in a foundry is that all these controls have to work together in a hot, heavy, dusty environment. The LEV has to cope with heat and capture fume and dust in tough conditions; the heat-control ventilation mustn't disrupt the fume and dust capture (air movements can pull fume away from hoods); the controls have to fit around heavy, hot work. So it takes proper design to get a coordinated system that manages heat, fume and dust together without one undermining another. And it takes maintenance and testing to keep it working: a foundry's extraction works hard in harsh conditions (heat, abrasive dust, heavy use), so it's prone to wear and degradation, and it has to keep performing to keep protecting workers. LEV controlling fume and dust must be maintained and thoroughly examined and tested regularly (typically at least every fourteen months) - especially important given the harsh conditions (covered in the foundries-lev-under-the-extreme-conditions-of-hot-work page). The hierarchy and health surveillance. Underlying it all, foundries apply the hierarchy of control (reducing the hazards at source where possible - better processes, less hazardous materials - before relying on capture and RPE) and health surveillance (monitoring workers' health to catch early signs of harm from the fume, dust and heat). So the management is systematic: reduce what you can, control the rest with coordinated ventilation, LEV, heat measures and RPE, keep it all working, and monitor health as a backstop. The takeaway. So foundries manage heat, fume and metal exposure with a coordinated combination of controls - ventilation, cooling and work practices for heat; LEV (backed by RPE) for metal fume; dust control and RPE for silica dust - all designed to work together in a harsh environment, kept maintained, with the LEV tested, and backed by the hierarchy of control and health surveillance. It's demanding because the hazards are severe and simultaneous, so the controls must be effective, coordinated and sustained. This is general information, not a substitute for a proper assessment. This is general information.
Key points
The hazards, all at once
A foundry's work - melting metal in furnaces, pouring molten metal, casting, and making and breaking sand moulds - generates several serious hazards together. Heat: furnaces and molten metal create intense heat, so workers face heat stress, which can cause heat exhaustion or worse. Metal fume: when metal is melted and poured, it gives off metal fume (fine metal-oxide particles, like welding fume) - breathing which can cause metal fume fever (a flu-like illness) and, depending on the metal, other effects, some metals being more toxic than others.
Silica dust: the sand used for moulds and cores contains silica, and handling the sand, making moulds, knocking out castings and finishing them releases silica dust - a serious cause of silicosis (an irreversible lung disease) and linked to other lung disease and cancer. And other hazards: gases, other dusts and fumes, noise, and heavy manual handling. So a foundry worker can face heat, fume and dust at the same time - the hazards overlapping in place and time. This simultaneity is what makes the environment so demanding to control: you can't deal with one hazard in isolation, because they occur together. So the hazards, all at once - heat, fume, silica dust and more together - is the challenge: several severe hazards, simultaneously, to be managed as a whole. How each is managed follows. So a foundry concentrates several serious hazards at once. This is general information. This is general information.
Managing the heat
Heat is managed with a combination of measures, because a foundry's heat (from furnaces and molten metal) is intense and can't be removed entirely. General ventilation removes hot air and brings in cooler air, lowering the ambient temperature. Cooling and heat shielding screen workers from radiant heat (shields and screens between workers and hot sources) and provide cooling. Sensible work practices - rest breaks, job rotation, and pacing work - limit how long workers are exposed to the heat at a stretch. Hydration is encouraged (drinking to replace fluid lost through sweating, which is considerable in the heat). And appropriate heat-protective clothing protects against radiant heat and hot materials.
The aim is to keep workers from overheating despite the hot environment - a matter of both comfort and safety, because heat stress can be dangerous (heat exhaustion, and in extreme cases heat stroke). Managing heat is partly about the environment (ventilation, shielding) and partly about the work and the worker (breaks, rotation, hydration, clothing) - a combination, since the heat can't simply be extracted away like a contaminant. Importantly, the heat-control ventilation has to be arranged so it doesn't disrupt the fume and dust capture (covered later). So managing the heat - ventilation, cooling, work practices and hydration - is the first strand: keep workers from overheating through a mix of environmental and work-practice measures. Fume is next. So heat is managed with ventilation, cooling, breaks and hydration. This is general information. This is general information.
Managing the metal fume
Metal fume is managed mainly with local exhaust ventilation (LEV) to capture the fume at source - over furnaces, at pouring and casting points, and at other fume-generating steps - drawing it away before workers breathe it. Because fume rises on the hot plume of the molten metal, the LEV has to be designed to catch that rising fume (typically capturing above and over the hot source, working with the plume). Capturing the fume at source is the key control, because it removes it from the air rather than relying on workers' protection alone.
Where LEV can't fully control the fume - some foundry tasks are mobile, large-scale, or awkward to extract from - respiratory protection (RPE) backs it up, protecting the individual worker where source capture isn't complete. The type of metal matters: some metals give off more toxic fume than others (and some carry specific risks), so the fume control is matched to the metals used - more toxic metals needing tighter control. So metal fume is managed by capturing it at source with well-designed LEV, backed by RPE, and matched to the metals involved. This connects to the general point that welding-type fume needs good capture (covered in the lev-testing-for-welding-fume page). So managing the metal fume - LEV at source, backed by RPE - is the second strand: capture the rising fume at source, back it with RPE, match it to the metal. Silica dust is next. So capture the metal fume at source with LEV, plus RPE. This is general information. This is general information.
Managing the silica dust
Silica dust is managed by controlling the dust from every dusty step in the foundry - because silica dust arises across the sand-related work, not at one point. The dusty steps include sand handling and mixing, moulding (making the sand moulds and cores), knockout (breaking the sand mould off the finished casting, a very dusty operation), and fettling and finishing (grinding and cleaning up castings). Each needs its dust controlled.
The controls include dust suppression (dampening down to stop dust becoming airborne), enclosure of dusty processes (containing the dust), local exhaust ventilation to capture the dust at source, good housekeeping (not letting settled dust build up and get re-disturbed - and never dry-sweeping, which re-raises it), and RPE where needed. Silica is a serious hazard - silicosis is an irreversible lung disease, and silica is also linked to other lung disease and cancer - so the dust control has to be effective and sustained, not occasional (in line with the cumulative nature of dust exposure). So managing the silica dust - dust control at every dusty step - is the third strand: control the silica dust across all the sand-related work, effectively and consistently, because silica causes serious irreversible disease. Making these controls work together is next. So control silica dust at every step, effectively and consistently. This is general information. This is general information.
Making it all work together
The real challenge in a foundry is that all these controls have to work together in a hot, heavy, dusty environment - and can undermine each other if not coordinated. The LEV has to cope with heat and capture fume and dust in tough conditions. The heat-control ventilation mustn't disrupt the fume and dust capture (strong air movements for cooling can pull fume away from hoods, so the two have to be designed together). The controls have to fit around heavy, hot, physical work. So it takes proper design to get a coordinated system that manages heat, fume and dust together without one undermining another - not just individual controls bolted on.
And it takes maintenance and testing to keep it working. A foundry's extraction works hard in harsh conditions - heat, abrasive dust, heavy use - so it's prone to wear and degradation, and it has to keep performing to keep protecting workers. LEV controlling fume and dust must be maintained and thoroughly examined and tested regularly (typically at least every fourteen months) - especially important given the harsh conditions, which make degradation more likely (covered in the foundries-lev-under-the-extreme-conditions-of-hot-work page). Underlying it all, foundries apply the hierarchy of control (reducing the hazards at source where possible before relying on capture and RPE) and health surveillance (monitoring workers' health to catch early signs of harm from the fume, dust and heat). So making it all work together - coordinated controls, kept maintained and tested - is the key: a designed, coordinated, maintained system, backed by the hierarchy and health surveillance, is how a foundry manages its severe, simultaneous hazards. So coordinate the controls and keep them working. This is general information, not a substitute for a proper assessment. This is general information.
Questions
Several serious ones at once: intense heat from furnaces and molten metal, metal fume from melting and pouring (which can cause metal fume fever), silica dust from moulding sand (a cause of silicosis), plus gases, other dusts, noise and heavy manual handling - the simultaneity is what makes foundries so demanding. Foundry workers face several serious hazards at once, because a foundry melts metal, pours and casts it, and works with sand moulds - all hazardous. Heat: furnaces and molten metal create intense heat, so workers face heat stress, which can cause heat exhaustion or worse. Metal fume: melting and pouring metal gives off metal fume (fine metal-oxide particles, like welding fume), which can cause metal fume fever (a flu-like illness) and, depending on the metal, other effects - some metals are more toxic than others. Silica dust: the sand for moulds and cores contains silica, and handling sand, moulding, knocking out castings and finishing them releases silica dust - a serious cause of silicosis (an irreversible lung disease) and linked to other lung disease and cancer. And other hazards: gases, other dusts and fumes, noise, and heavy manual handling. So a foundry worker can face heat, fume and dust simultaneously, which is what makes the environment so demanding - the hazards can't be dealt with in isolation. So they face heat, metal fume, silica dust and more together. So heat, fume, silica dust and other hazards at once. This is general information. This is general information.
It's a flu-like illness (fever, chills, aches) caused by breathing metal fume - the fine metal-oxide particles given off when metal is melted and poured; it's one effect of metal fume exposure in foundries (and welding), and some metals cause other, more serious effects, so metal fume is captured with LEV. Metal fume fever is a flu-like illness caused by breathing metal fume - the fine metal-oxide particles given off when metal is melted, poured and cast (the same kind of fume welding produces). Its symptoms are flu-like: fever, chills, aches, and general malaise, typically coming on after exposure. It's one of the effects of breathing metal fume in a foundry (or in welding). While metal fume fever itself is usually short-lived, it's a clear sign of significant fume exposure, and metal fume can have other, more serious effects too - depending on the metal involved, some metals are more toxic and carry specific health risks beyond metal fume fever. So metal fume is a real health hazard that has to be controlled, not shrugged off. In foundries, metal fume is managed mainly by capturing it at source with local exhaust ventilation (LEV) - over furnaces and at pouring and casting points, catching the fume as it rises on the hot plume - backed by respiratory protection where LEV can't fully control it, and matched to the toxicity of the metals used. So metal fume fever is a flu-like reaction to metal fume, one reason foundry fume must be captured. So a flu-like illness from breathing metal fume. This is general information, not clinical advice. This is general information.
Because the moulding sand contains silica, and sand handling, moulding, knockout and finishing release silica dust - a serious cause of silicosis (an irreversible lung disease) and linked to other lung disease and cancer; it arises across many steps, so it's controlled with suppression, enclosure, LEV, housekeeping and RPE. Silica dust is a concern in foundries because the sand used for moulds and cores contains silica, and the foundry's sand-related work releases silica dust across many steps. Those dusty steps include sand handling and mixing, moulding (making the sand moulds and cores), knockout (breaking the sand mould off the finished casting - a very dusty operation), and fettling and finishing (grinding and cleaning castings). Silica dust is a serious health hazard: it's the cause of silicosis (an irreversible, progressive lung disease), and it's also linked to other lung disease and to lung cancer. Because it arises at many steps and causes serious irreversible disease, silica dust has to be controlled effectively and consistently. The controls include dust suppression (dampening down), enclosure of dusty processes, local exhaust ventilation to capture the dust at source, good housekeeping (never dry-sweeping, which re-raises settled dust), and RPE where needed. As silica harm is cumulative (building over years of exposure), the control has to be sustained, not occasional. So silica dust is a concern because it causes serious irreversible lung disease and arises across the foundry's sand work. So because it causes silicosis and arises across many steps. This is general information, not clinical advice. This is general information.
Mainly with local exhaust ventilation (LEV) capturing fume at source over furnaces and pouring points (catching the rising plume) and dust at every dusty step, backed by RPE where capture isn't complete, plus suppression and enclosure for dust - with the LEV maintained and tested because it works hard in harsh conditions. Foundries control metal fume and silica dust mainly with local exhaust ventilation (LEV), backed by other measures. For metal fume: LEV captures it at source - over furnaces, at pouring and casting points, and other fume-generating steps - drawing it away before workers breathe it. Because fume rises on the hot plume of the molten metal, the LEV is designed to catch that rising fume (capturing above and over the source). Respiratory protection (RPE) backs it up where LEV can't fully control the fume, and the control is matched to the toxicity of the metals used. For silica dust: LEV captures dust at the dusty steps (sand handling, moulding, knockout, finishing), alongside dust suppression (dampening down), enclosure of dusty processes, good housekeeping (no dry-sweeping), and RPE. Crucially, because a foundry's LEV works hard in harsh conditions (heat, abrasive dust, heavy use), it's prone to wear and must be maintained and thoroughly examined and tested regularly (typically at least every fourteen months) to keep capturing effectively. So fume and dust are controlled by capturing them at source with well-maintained, tested LEV, backed by RPE and dust-suppression measures. So mainly with LEV at source, backed by RPE, kept tested. So with source-capture LEV, RPE and dust control, maintained. This is general information. This is general information.
Because heat, fume and dust occur simultaneously in a harsh environment, and the controls can undermine each other - cooling airflow can pull fume from hoods, the LEV must cope with heat and abrasive dust - so it takes coordinated design and sustained maintenance and testing, not individual controls bolted on. Controlling all a foundry's hazards together is hard because they occur simultaneously in a hot, heavy, dusty environment, and the controls can undermine each other if not coordinated. Several tensions arise. The LEV has to cope with heat and capture fume and dust in tough conditions (heat and abrasive dust are hard on extraction). The heat-control ventilation mustn't disrupt the fume and dust capture - strong air movements introduced for cooling can pull fume away from extraction hoods, so the cooling and the capture have to be designed together, not separately. And all the controls have to fit around heavy, hot, physical work. So it takes proper, coordinated design to manage heat, fume and dust together without one undermining another - individual controls bolted on independently can conflict. On top of that, it takes sustained maintenance and testing: a foundry's extraction works hard in harsh conditions and is prone to wear and degradation, so it has to be kept maintained and (for the LEV) tested to keep performing. So the difficulty is the combination of simultaneous severe hazards, a harsh environment, and controls that must be coordinated and kept working. So because the hazards and controls interact and the conditions are harsh. So because the controls interact and the environment is punishing. This is general information. This is general information.
Yes - and especially so; LEV controlling metal fume and silica dust is controlling serious health hazards under COSHH, so it must be thoroughly examined and tested regularly (typically at least every 14 months), and because a foundry's extraction works hard in harsh conditions it's more prone to degrade, making the testing all the more important. Yes - a foundry's LEV needs regular testing, and the harsh conditions make it all the more important. LEV controlling metal fume and silica dust is controlling serious health hazards (metal fume and silicosis-causing silica dust), so under COSHH it must be maintained and thoroughly examined and tested regularly - typically at least every fourteen months for most systems - to confirm it's still capturing the fume and dust. What makes it especially important in a foundry is the environment: the extraction works hard in harsh conditions (intense heat, abrasive dust, heavy continuous use), which make it more prone to wear and degradation than LEV in a gentler setting. So a foundry's LEV is both critical (controlling severe hazards) and vulnerable (working in punishing conditions), so keeping it proven to work through regular testing is doubly important. A degraded foundry LEV that's no longer capturing the fume and dust leaves workers exposed to serious, sometimes irreversible harm. So the testing confirms the hard-working extraction is still protecting workers. So yes - and the harsh conditions make regular testing especially important. So yes; and especially so, given the tough conditions. This is general information. This is general information.
A foundry's LEV works hard in harsh conditions to capture metal fume and silica dust - and has to keep performing to keep protecting workers; we thoroughly examine and test foundry LEV in those tough conditions, confirming it still captures the fume and dust, as COSHH requires and the severe hazards demand. Ask us to test your LEV. This is general information.
