Health and Safety
Executive / Commission
Rubber industry
The case studies in this section are real. They show both the benefit to companies which have taken aproactive approach to health and safety and the real consequences and harm to those involved in the incidents described in the case studies.
A company used manually operated devices to turn and consolidate rubber components during tyre building. This was a repetitive task which not only caused work-related upper limb disorders (WRULDs) and subsequent sickness absence but fatigue and lack of concentration amongst operators meant that they exerted a variable manual force on the product. This affected the product quality.
Training staff in manual handling led to discussion of this WRULD problem, and the company decided to replace the manual devices with mechanical aids. The uniformity of force and positioning to within specified tolerances achieved by the new process far exceeded that of the previous work method. This resulted in improved quality of the product.
Sickness absence reduced significantly as the incidence of WRULDs decreased and the morale of employees improved. The company had also taken action which could result in reduced liability insurance premiums.
Transport managers in a large company were given health and safety training for the first time. Part of the course involved identifying an area of concern within their company and devising ways of dealing with it. They identified the number of incidents involving forklift trucks.
The managers decided to design a new traffic management system, tackling the problem by separating and directing forklift truck and pedestrian traffic wherever possible. Existing forklift truck drivers and other employees were trained in the new system when it was introduced. It was also included in induction training for new employees and forklift truck drivers. Transport flow within the factory was significantly improved, reducing the risk of accidents. In addition, the flow of components throughout the factory was quicker, contributing to more efficient production.
High dust levels during weighing and mixing operations were causing a major problem for one company in the rubber industry. There were persistent complaints from employees, and dust measurements made as part of the company’s COSHH assessment showed that employee exposures were above the statutory control limits.
Operatives were trained in a new system which concentrated on reducing the escape of dust during weighing and mixing. Wherever possible dust-suppressed forms of chemicals were introduced. The working practices (e.g. bag emptying, bag disposal, weighing and transfer) were studied and techniques for reducing the generation and escape of dust devised.
An employee who was mixing a caustic solution used for cleaning rubber moulds suffered scalding and burns when he added pearl caustic to hot water. The contents of the mixing drum had bubbled over. The employee had not been trained and so did not know that the pearl caustic should be added to cold water.
A powder weighing operative suffered a fractured vertebra while lifting 25kg bags of chip material from floor level to a bin which was two metres away and one metre above the floor. The task had not been assessed nor had the operator been trained in appropriate techniques.
There had been problems with a moulding press and the operator was purging the machine at the request of the engineer who was attempting to resolve the problems. The operator was working near the top platen. The engineer operated the bottom platen not realising that the top platen would automatically move sideways. The operator’s hand was trapped in the injection well when the platen moved. Neither had been properly trained in safe maintenance procedures for the machine.
A new teenage employee was injured at a tyre buffing machine when his shirt became entangled around the rasp on the articulated head of the machine. The open guard had failed to operate the safety interlock switch. Although the machine guard should have been properly maintained, the untrained operator did not have enough knowledge of the machine to realise that the guard was defective.
A Supervisor was overcome by toluene fumes when he was working in a different place to his normal working area. He had not received adequate training in the new work or the risks associated with it. In particular he had not been specifically trained to understand the hazards of toluene and the importance of switching on the extraction system before beginning work.
A machine making rubberised fabric required operators to load product reels weighing over 30kg. A hoist had been provided in the past but operators did not use if because of the extra time it took. By altering the process slightly, it became possible to make much larger product rolls, which doubled the weight; so mechanised lifting had to be reintroduced and made to work effectively. This time a counterbalance hoist was used with a more user-friendly mechanism and the eventual make of hoist was only decided after the operators had the opportunity to see and try the different types available. The hoist was accepted well by the operators.
The two roll mill consisted of two rolls of about 650 mm diameter and 1525 mm length. The rolls were set horizontally next to each other and a gap of about 10 mm between them.
The machine could be operated from either the front or back and a safety bar (Lunn bar) was fitted to both operating positions. Both bars, when pushed operated one interlocking switch via a mechanical linkage.
The operation involved feeding cold uncured rubber onto the rotating rolls which was then taken through the gap between them. This produced warm tacky rubber. When it was warm enough, the rubber was cut and placed on a conveyor to be taken for further processing.
On this occasion, the operator’s gloved had became stuck on the warm tacky rubber and was drawn into the nip between the two rolls, lifting him off the floor. He was drawn against the Lunn bar, pushing it, but if failed to operate the interlocking switch and stop the rolls. With his free hand he continued to push the Lunn bar which stopped the rolls several seconds later.
The operator’s hand was badly crushed, resulting in the amputation of four fingers.
The Lunn bar failed to operate the interlocking switch because it hadn't been properly maintained, there was too much free-play in the mechanical linkage and a retaining pin in the linkage was not fully engaged.
NB: this single interlock did not meet the industry standard which is for each Lunn bar to be fitted with two electrical interlocking switches, one at each end of the bar, each switch should be positively operated. Pressing the Lunn bar should stop the rolls moving.
A Tyre company was fined £100,000 and ordered to pay costs of £12,500 following an incident when an employee caught his hand in work equipment. At the time of the incident the employee was working on a machine which ground the tread from old tyres for re-use. A rotary valve controlled the flow of crumb down a chute into the collection bags, there was also a grill at the bottom of the chute. In an effort to prevent blockages the company had removed the grille and shortened the chute to about 410mm, this allowed access to the moving parts. When the employee reached up into the chute to clear a blockage his fingers became caught in the equipment and three of his fingers were removed up to the first knuckle.