OHS in Foundries: Molten Metal and Moulding Sand

Why should foundry safety be dealt with department by department?

Bursa's automotive and machinery industry needs cast iron, steel and aluminium parts; the foundries that produce them house very different risks under one roof. Dust dominates in sand preparation, explosion and heat in melting, splashes and heavy loads on the pouring line, and noise and vibration in shakeout and fettling. Foundry safety is therefore managed not with a single general risk list but with a risk assessment prepared department by department.

Department	Main hazard	Priority measure	Related health surveillance
Sand preparation, moulding and coremaking	Quartz-bearing dust, resins and hardener chemicals	Closed system, local exhaust ventilation, wet methods, respiratory protection	Chest X-ray (ILO), lung function test
Melting	Steam explosion on contact with water, heat, infrared radiation	Dry and preheated charge, permit to work for furnace maintenance, IR-filter eye protection	Eye examination, fitness-for-heat assessment
Pouring	Molten metal splashes, ladle transport, cranes	Dry moulds and tools, separate ladle routes, heat-resistant PPE	Burn and first aid preparedness
Shakeout	Noise, dust, vibration	Enclosure, extraction, hearing protection	Audiometry, chest X-ray
Fettling and grinding	Dust, noise, hand-arm vibration, sparks	Extracted benches, guards, low-vibration tools, job rotation	Audiometry, chest X-ray, hand-arm examination

Writing down who is exposed and for how long in each department determines both the priority of measures and the health surveillance plan.

Melting furnace safety

The most serious risk in the melting department is molten metal meeting water or moisture. When water is trapped under molten metal it turns instantly into steam and its volume expands in a very short time; metal is thrown out of the furnace or ladle. Melting furnace safety is built around this physical fact:

Charge material must be dry. Wet, snowy or icy scrap is not fed into the furnace; damp material is dried or preheated first.
Sealed items are sorted out. Parts that may contain water or air, such as pipes, tubes, sealed boxes and shock absorbers, are cut open or removed before going into the charge.
Tools and ladles are heated. Slag skimmers, sampling spoons and ladles are dried and heated before use; a cold tool is never dipped into molten metal.
Cooling water is monitored. On induction furnaces, leak and flow alarms on the coil cooling water circuit are kept in working order; refractory wear is measured regularly.
Furnace maintenance is tied to a permit to work. Non-routine work such as removing refractory, relining and entering the furnace is done under a written permit to work; for details see our article on the permit to work system.

Employees in the melting department are also exposed to the infrared radiation given off by molten and incandescent metal. The list of occupational diseases defines cataract caused by infrared radiation with a 3-year liability period, specifically including work facing molten metal in foundries; eye protection therefore needs to have an infrared filter.

Molten metal splashes on the pouring line

Molten metal splashes usually have two causes: contact with a damp mould, core or floor during pouring, and uncontrolled ladle movement. The measures are:

Moulds and cores must be fully dry; the floor of the pouring area must be kept dry, with no pits or pools of water.
Ladle transport routes must be separated from walkways; nobody should be under the ladle or in the pouring direction during pouring.
The lock on the ladle tilting mechanism and the crane brakes should be checked daily. Under Annex III of the Regulation on Work Equipment, overhead cranes and cranes undergo periodic inspection once a year unless the standard specifies a shorter interval.
A dry area or sand bed where metal spilled in an emergency will be collected should be designated in advance.

Foundry sand, silica and core chemicals

Most moulding and core sands contain quartz. The fine dust produced during sand preparation, moulding, shakeout and especially fettling causes permanent lung damage when inhaled. The list of occupational diseases provides a 10-year liability period for silicosis and explicitly lists fettling, surface finishing and sandblasting in foundries using sand among the work with a disease hazard. We explained which group it belongs to and how the period is calculated in our article on the list of occupational diseases.

Foundry sand silica risk is managed under the Regulation on Dust Control:

The risk assessment takes into account the type of dust, the level and duration of exposure, the limit values in Annex 1 and the measurement results (Art. 6).
Dust measurements are carried out by laboratories holding an accreditation certificate from the General Directorate of Occupational Health and Safety (ISGGM), at intervals set by the risk assessment and when exposure conditions change (Art. 8). We plan measurements with authorised laboratories and healthcare providers.
If the limit value is exceeded, dust is reduced at source, the measurement is repeated and work is permitted once the value has fallen to a suitable level (Art. 9).
At workplaces where quartz-bearing dust may be present, chest X-rays are taken according to the ILO classification and assessed by a reader; the workplace physician sets the frequency.

The order of control measures matters: closed sand preparation and transport, local exhaust ventilation at the shakeout grid and fettling benches, wet methods, vacuum cleaning instead of sweeping, a ban on cleaning clothes with compressed air and, last of all, respiratory protection. For details of the regulation, see our article on the Regulation on Dust Control. To learn the hazards of the resins and hardeners used in coremaking, read the products' safety data sheets; whether chemical exposure measurement is needed is decided on the basis of this information.

Shakeout, fettling and noise

The Ministry's guide to noise control in the foundry sector lists moulding, working at the shakeout, grinding and finishing among the main noise sources in foundries. The values of 80, 85 and 87 dB(A) can be exceeded in these departments; for determining exposure with personal dosimeters and for a noise map, see our article on workplace noise measurement.

In the fettling department, grinding and blasting tools also produce hand-arm vibration; the list of occupational diseases defines vibration-related bone and joint damage with a 2-year liability period. Choosing low-vibration tools, maintaining tools and job rotation should be applied together. Setting guards and tool rests on grinding machines and keeping sparks away from combustible material are also basic rules in this department.

Heat, working hours and the shift plan

Art. 4 of the Regulation on Work Which, for Health Reasons, Must Be Limited to a Maximum of Seven and a Half Hours a Day or Less, published in Official Gazette No. 28709 of 16 July 2013, states that an employee in foundry work may work only 7.5 hours a day. The work covered is:

Preparing moulding sand.
Making casting moulds and cores and getting them ready for pouring.
Preparing the furnace charge and getting metal melting furnaces ready for pouring.
Metal melting and pouring.
Shaking out moulds and fettling castings.
Centrifugal and vertical casting.

The shift plan and timekeeping should be built around this limit. In the melting and pouring departments, where the heat load is high, a cool rest area, easy access to drinking water and gradual acclimatisation for new starters are also planned. The Regulation on Workplace Buildings and Premises also requires measures to protect employees from heat where continuous work in a very hot environment is unavoidable.

Foundry PPE and training

Foundry PPE is chosen by department. In melting and pouring, an apron or clothing protecting against heat and molten metal splashes, a hard hat with face shield, eye protection with an infrared filter, heat-resistant gloves and boots that can be removed quickly when needed, with spats, are key; in the sand, moulding and fettling departments, respiratory protection, hearing protection and eye protection come to the fore. Which risk a product protects against is stated in the user information for CE-marked products; make the selection based on the risk assessment and provide PPE to employees free of charge. For the process, see our article on how to select PPE.

In training, foundry-specific risks (water and molten metal, ladle transport, silica, noise, heat) should be covered face to face in the fourth topic group. To check your workplace's hazard class from your code, see our hazard class guide, and to see whether the work done requires a vocational training certificate, our article on jobs requiring vocational training.

For foundries, we carry out department-based risk assessment under our risk assessment service and on-site follow-up under our OHS specialist service. For sector notes, see our metal and machinery and automotive supply industry pages, and to track measurement and inspection dates, the OHS calendar tool.

Frequently Asked Questions

How many hours a day can employees work in a foundry?

In moulding sand preparation, mould and core making, charge and furnace preparation, metal melting and pouring, shakeout and fettling, an employee can work at most 7.5 hours a day.

How is the silica risk in foundry sand measured?

Dust measurement is carried out by a laboratory holding an accreditation certificate from ISGGM. The measurement interval is set by the risk assessment, the measurement is repeated when exposure conditions change, and the result is compared with the limit values in Annex 1 of the Regulation on Dust Control.

Why does molten metal explode?

When molten metal comes into contact with water or moisture, the water instantly turns into steam and its volume expands very rapidly. This pressure throws metal out of the furnace or ladle. Wet charge, cold tools and damp moulds are the main causes.

What health tests are carried out on foundry employees?

Chest X-rays in line with the ILO classification for those exposed to quartz-bearing dust, audiometry in noisy departments and, where necessary, lung function tests and eye examinations. The workplace physician determines the type and frequency of tests based on the risk assessment.