Brick Factories: Kilns, Dust and Manual Handling

Brick factory safety: risks along the production flow

In a brick or roof tile factory, clay moves along the same line from the clay pit to the dispatch yard, but it carries a different hazard at every stop. Brick factory safety should therefore be addressed not under a "factory-wide" heading but separately for each section of the flow. Wet clay creates trapping risks in machinery, dried clay becomes dust, the kiln means heat and gas, and the fired product becomes thousands of pieces to be handled manually.

Each row in the table should be a separate heading in the risk assessment file. Ceramics and porcelain plants carry similar hazards but have additional sections such as glazing and decoration; we covered them in our article on ceramics and porcelain in Kütahya.

Clay preparation and shaping: trapping and confined spaces

The clay preparation line consists of a box feeder, coarse and fine rollers, a mixer and a vacuum extruder. What these machines have in common is that they move the clay forward by compressing it. The same force also draws in a hand or arm.

The most common dangerous behaviours seen on site are:

1. Pushing clay into running rollers: When clay bridges between the rollers, the operator pushes it with a stick or by hand without stopping the machine. A fixed guard that prevents approaching the roller inlet and a long tool designed for pushing should be used.
2. Running the mixer with the cover open: The mixer cover should be interlocked; the machine should stop when the cover is opened.
3. Adjustments at the extruder mouth and cutting wire: When the cutting wire is being changed or the die cleaned, the machine must be prevented from restarting.
4. Entering hoppers and silos: An employee who enters a hopper to clear clay stuck to the walls can be buried under sliding clay. This work is carried out under a confined space entry permit, with the feeder's energy isolated and locked out and with a standby person outside.

All breakdown, cleaning and maintenance work should be tied to the lockout and tagout procedure. For choosing the type of guard, see our article on machine guarding.

Brick factory dust sources and measures

Wet clay does not produce dust; the problem starts when the clay dries. Brick clays mostly contain quartz, and this proportion varies with the clay pit. Brick factory dust sources are usually:

• Crushing dry clay and earthmoving machinery movement in the stockyard
• Dried product and broken pieces spilling from conveyor belts
• Cleaning kiln cars and deposits in the channels under the kiln
• Dust from fired product during unloading and sorting
• Dry sweeping and cleaning with compressed air

Measures are ranked according to the hierarchy of controls: damping down the stockyard and roads, enclosure and local exhaust ventilation at transfer points, regular wet cleaning under belts, and an industrial vacuum with a HEPA filter instead of dry sweeping. Respiratory protection comes after these measures. We described the health effects of quartz-bearing dust in our article on crystalline silica dust, and the employer's obligations under the regulation in our article on the Regulation on Dust Control.

We plan dust measurement with authorised laboratories and record the results in the risk assessment. For which sections and which parameters the measurement should cover, see our article on respirable and total dust measurement. The measurement result can affect not only the choice of measures but also working hours: the list of jobs to be worked 7.5 hours a day or less includes "work in workplaces where dusts causing pneumoconiosis are present"; assess your dusty sections from this angle too.

The brick kiln: heat, gas and kiln cars

Bricks and roof tiles are fired at temperatures approaching a thousand degrees. In modern plants the product passes through a tunnel kiln on kiln cars running on rails; some plants still use ring-type (Hoffmann) kilns, where setting and unloading are done manually in hot chambers. The risks in the brick kiln section fall into four groups:

• Heat stress: Employees at the kiln entrance, at the exit of the cooling zone and in the chambers of ring kilns are exposed to intense heat. Water, a cool rest area and a break plan in hot periods are needed. We explained how heat stress is assessed in our article on heat stress at the furnace (WBGT); we plan thermal comfort measurements with authorised laboratories.
• Gas: In kilns running on natural gas, coal or other fuels, incomplete combustion produces carbon monoxide. The upper sections of ring kilns where fuel is fed and the channels under the kiln should be assessed separately from this angle.
• Mechanism: The pushers, transfer cars and rail systems that move kiln cars create trapping and crushing hazards. The movement area should be separated by guardrails or light barriers.
• Burns: Product and cars leaving the cooling zone are still hot; burns occur even with brief contact. Heat-resistant gloves and long-sleeved workwear should be used.

Brick stacking and back strain in manual handling

A single brick is light; the problem is frequency. In unloading from kiln cars, sorting and brick stacking onto pallets, the same movement is repeated thousands of times per shift.

Example calculation: Assume an employee transferring a product weighing 3 kg each from a kiln car to a pallet handles 2,500 units per shift. That means 7.5 tonnes of load per shift and an average of 5–6 lifts per minute over a 7.5-hour working day. If the lifts start from the bottom of the pallet, i.e. well below waist height, the load becomes even heavier for the back. Even if the weight of a single lift looks low, the total load and frequency are the real cause of musculoskeletal disorders.

This calculation shows that, under the Regulation on Manual Handling, frequency and posture must be addressed in the risk assessment together with the weight of the load. Practical measures:

1. Height-adjustable pallet station: A lifting table or spring-loaded pallet table keeps the stack between waist and shoulder height.
2. Mechanical setting and unloading: A robot, vacuum gripper or manipulator directly reduces the number of repetitions.
3. Rotation: Within-shift rotation is arranged between unloading and sorting tasks.
4. Personal protection: Cut-resistant gloves against broken edges and toe-capped safety footwear against falling pieces are provided.
5. Stack safety: The height of packs is limited, strapping and stretch wrapping are done securely, and stacking is not done on sloping ground.

To calculate the load limit according to frequency, see our article on how much weight can be lifted, and for correct lifting technique, see our article on manual handling and lifting technique.

Training, health surveillance and periodic inspections

Verify your hazard class from the NACE code on İSG-KATİP (the Ministry's online OHS registration system); the duration of basic training, its repeat frequency and the periodic examination interval are determined accordingly. Every new employee, even if seasonal or temporary, receives at least 2 hours of face-to-face induction training before starting work. The job- and workplace-specific risks section of basic training is delivered face to face in hazardous and very hazardous workplaces; roller, kiln car and dust risks should be explained in this section by demonstrating them on site.

In health surveillance, the workplace physician determines the frequency of chest X-rays meeting the ILO classification for employees working with dust. If noise in clay preparation and shaping exceeds the upper exposure action value of 85 dB(A), hearing tests are mandatory; these sections should also be measured for noise.

Forklifts, conveyors, compressor tanks, internal electrical installations and earthing, and fire installations in the factory are subject to annual periodic inspection. Having these inspections carried out by authorised persons registered on EKİPNET (the Ministry's register of authorised inspectors) is the employer's obligation; through our periodic inspection service, delivered via our solution partners, we plan the dates and follow up the closure of shortcomings in the reports. You can use the OHS calendar tool to track the dates.

For brick and roof tile manufacturers in Bursa and the surrounding provinces, Bursa Sistemer carries out section-based site walks and risk assessment together as part of the OHS specialist service. For other topics for building materials manufacturers, see our construction sector page.

Frequently Asked Questions

Where do accidents happen most often in a brick factory?

Trapping accidents in clay preparation machinery, particularly when clearing blockages in rollers and mixers, and in the kiln car mechanism have the most serious consequences. The most frequent complaints by number, however, are back and shoulder strain in unloading and stacking.

Which mask should be used for clay dust?

Damping down, enclosure and local exhaust ventilation should be provided first. For the remaining exposure, a protector with a particle filter is chosen; its class is determined according to the measurement result, and the fit of the mask to the face is checked.

What should be done when a kiln car jams?

The line is stopped, and the energy to the pusher and transfer systems is isolated and locked out. If entry into the kiln is needed, it is left to cool, gas measurement is carried out, and the work is done under a confined space permit with a standby person outside.

How many kilos can be lifted when unloading bricks?

The legislation does not give a single kilogram limit. A safe load is calculated according to the frequency, height, trunk twisting and duration of the lift. Even with light products, high frequency can require a lifting table or mechanical setting.