In brief
Most conveyor accidents happen at the in-running nip points where the belt wraps around the drum and between rollers, usually while cleaning a running line or removing jammed product. The Work Equipment Regulation requires guards that cannot easily be defeated, an emergency stop where necessary, and maintenance carried out with the equipment stopped and its energy isolated. Periodic inspection of conveyors is carried out at least once a year.
Why does conveyor safety start with nip points?
A conveyor is one of the quietest pieces of equipment in a factory, which is why its hazard is easily forgotten. Conveyor safety starts with managing the trapping risk at the points where the belt or chain meets a rotating element. As the belt wraps around a drum, an in-running nip forms between the two that draws things inwards. A glove, cloth or arm that touches this line is drawn in before the belt stops. This risk is more common on food lines, because belts are cleaned every shift and product jams invite manual intervention.
This article covers nip points on belt and roller conveyors, pull-cord emergency stops, cleaning rules and periodic inspection. For the general principles of machine guarding, see our article on machine guards.
Where are the nip points on a belt conveyor?
Belt conveyor nip point risks are concentrated at specific points. Walk your line and inspect it against these points.
| Point | How does it trap? | Typical protection |
|---|---|---|
| Drive drum | Draws in at the in-running point as the belt wraps around the drum | Fixed guard enclosing both sides of the drum and the in-running area |
| Return and take-up drum | The same nip at the end of the line; frequently accessed during tension adjustment | Fixed guard; adjustment point moved outside the guard |
| Snub and bend drums | In-running points on the belt's return side, out of sight | Guard enclosing the return side or protection by distance |
| Between carrying and return rollers and the belt | A small but effective nip at every point where the belt presses on a roller | Enclosure at accessible heights, roller zone protection under load |
| Drive rollers and chain/belt on roller conveyors | Trapping between driven rollers and at the chain sprocket | Chain and sprocket enclosure, filler plates between rollers |
| Transfer point | Product and hands get trapped at the transfer from one belt to another | Transfer plate, design that reduces product jams |
| Motor, gearbox and coupling | Rotating shaft and coupling | Fixed enclosure |
In drum conveyor designs, the most dangerous area is often the one the operator looks at least: the return side under the belt and the take-up drum at the end of the line. Safety distance standards determine how much the guards must enclose; when fitting a fixed guard, make sure the openings do not allow fingers or arms to reach the danger point.
Guards: fixed or interlocked?
Annex I of the Regulation on Health and Safety Requirements for the Use of Work Equipment requires guards against the risk of contact with moving parts and requires guards to be such that they cannot easily be removed or rendered ineffective. The practical choice for conveyors is as follows:
- Fixed guard: Bolted enclosures that can only be removed with a tool. Suitable for drum and drive areas that are rarely accessed.
- Interlocked guard: For covers that are opened frequently. When the cover is opened the line stops, and it does not restart by itself when the cover is closed.
- Cleaning guards removable without tools: On food lines, guards frequently removed for cleaning must be used with an interlock arrangement that prevents the line from running when they are removed. Otherwise, once a guard is removed, production resumes without it being refitted.
The regulation also requires the operator to be able to make sure from the main control position that no one is in the danger zone, and on long lines where this is not possible, an audible and visual warning system that is automatically activated before start-up. A belt starting suddenly on a long packing line catches an employee who is cleaning unprepared.
What should a conveyor emergency stop pull cord be like?
Under the regulation, an emergency stop system is provided where the equipment's hazards and normal stopping time require it. On a short conveyor, an accessible emergency stop button may be enough. On long lines, however, every metre walked to reach the button is time lost at the moment of trapping. This is why a conveyor emergency stop pull cord, that is, pull-cord emergency stop switches stretched along the line, is used.
In a good pull-cord system, look for the following:
- The cord runs along the line on both sides where employees may be present and can easily be reached by hand from any point.
- The conveyor stops when the cord is pulled or breaks; the switch does not reset itself.
- When the switch is reset, the conveyor does not restart by itself. The regulation requires equipment to be started only by deliberate action on controls provided for that purpose; this rule also covers restarting after a stop.
- Cord tension and switches are tested regularly in line with the manufacturer's instructions; a test record is kept.
- Which switch has been triggered can be seen from the panel, so the person restarting the line knows where the person who stopped it is.
For the design and testing of emergency stops, see our article on emergency stop buttons. Remember: the emergency stop is the last resort in an accident; it is not a safe stopping method for cleaning and maintenance.
Conveyor cleaning: the safe method on food lines
Conveyor cleaning is done frequently and routinely in food businesses because it is part of the hygiene plan; the risk arises from this very routine. A safe cleaning instruction follows this sequence:
- Stop: The line is stopped using the normal stop control.
- Energy isolation: The motor supply is disconnected, locked and tagged; any pneumatic and hydraulic energy is also released. For the detailed method, see our article on LOTO lockout and tagout.
- Zero-energy test: Pressing the start button confirms that the line does not start.
- Cleaning: Guards are removed only as far as needed for cleaning; if chemicals are used, the PPE in the safety data sheet is worn and wet floors are marked.
- Reassembly: Guards are refitted, a check is made that no tools or cloths are left, the lock is removed and the line is started after a warning is given.
On some belts, the belt must be advanced to clean the whole surface. In this case, the belt is advanced in short increments while the person cleaning is out of the danger zone; if the manufacturer provides a separate low-speed setting mode, only that mode is used, under a defined instruction. Ease of cleaning should also be considered at the purchasing stage: guards that can be removed without tools but lock out the line when removed, and easily removable belt designs, reduce the pressure that pushes employees to intervene on a running line. For general risks of food machinery, see our article on food machinery safety.
Periodic inspection and daily checks
In Annex III of the Work Equipment Regulation, conveyors appear as "continuous handling equipment". Unless a shorter period is given in the relevant standard or the manufacturer's instructions, the periodic inspection interval is at most 1 year; TS EN 618+A1, TS EN 619+A1 and TS EN 620 are listed as the inspection criteria. The inspection is carried out by an engineer, technical teacher, technician or senior technician registered in EKİPNET (the Ministry's register of persons authorised to carry out periodic inspections); the person who maintains the equipment cannot carry out its periodic inspection. For all periods, see our article on periodic inspection intervals for work equipment, and for reading the report, our article on how to read a periodic inspection report.
The annual inspection does not replace a daily eye. A short check by the operator at the start of each shift can include the following:
| Daily check item | What to look for |
|---|---|
| Guards | In place, secure and undamaged |
| Pull-cord emergency stop | Cord taut; on a test stop the line stops and does not restart by itself |
| Start-up warning | Audible and visual warning working |
| Belt | No slipping, tears or edge wear |
| Floor | No build-up of product, water or oil under and beside the line |
| Interlocked covers | Line stops when the cover is opened |
In food businesses in Bursa and neighbouring provinces, on lines that run intensively in season, as in the tomato paste factories of Mustafakemalpaşa, it is especially important to carry out this check along the whole line at the start of the season and to show new employees the line on site. For other risks specific to the food sector, see our sector page. You can use our periodic inspection service to plan annual inspections with authorised persons and follow up non-conformities in reports, and our OHS specialist service to prepare guarding and cleaning instructions for your line.
Frequently Asked Questions
How often is a conveyor's periodic inspection carried out?
Under Annex III of the Work Equipment Regulation, for continuous handling equipment (conveyors), the maximum interval is 1 year unless a shorter period is given in the standard or the manufacturer's instructions. The inspection is carried out by authorised persons registered in EKİPNET.
Is a pull-cord emergency stop mandatory?
The regulation requires an emergency stop system where the equipment's hazards and stopping time require it; it does not specify the type. On long lines where a button cannot be reached quickly from every point, pull-cord switches running along the line are a practical way of meeting this requirement.
Can cleaning be done while the belt is running?
It should not be. The regulation requires maintenance to be carried out with the equipment switched off, its energy disconnected and its movement stopped; cleaning and removing jammed product should also be treated within this scope. If the belt needs to be advanced, it is done while the employee is out of the danger zone and under a defined instruction.
Can a conveyor start by itself when the emergency stop is reset?
No. The equipment must only be restarted by deliberate use of controls provided for that purpose. Resetting and restarting must be separate operations.
A certified specialist matched to your hazard class: site inspections, approved logbook, training plan, annual plan and report follow-up.
Bursa SİSTEMER OSGB Technical Team — written from the field experience of our OHS specialists and workplace physicians. Legal information is valid as of the publication/update date; contact us for an assessment specific to your business.