Design, manufacture, fitment, approval and testing of a bespoke water-based dust suppression system to 100 Network Rail Sidetipper Wagons to reduce exposure to Respirable Crystalline Silica faced by the Employer’s employees, contractors and other personnel involved in aggregate handling activities. In conjunction with this, modification of the Sidetipper Wagons to protect against inadvertent toppling due to partial chute opening is required. Additionally, the installation of the ‘Mark 2’ Sidetipper Handbrake Interlock system to the ‘Mark 1’ fleet is required.

The Technical Specification conveys the requirements for the design, manufacture, fitment, approval and testing of a bespoke water-based dust suppression system to 100 x Network Rail Sidetipper Wagons to reduce exposure to Respirable Crystalline Silica faced by the Employer’s employees, contractors and other personnel involved in aggregate handling activities. In conjunction with this, modification of the Sidetipper Wagons to protect against inadvertent toppling due to partial chute opening is required. Additionally, the installation of 50 x ‘Mark 2’ Sidetipper Handbrake Interlock system to the ‘Mark 1’ fleet is required.

Network Rail (the Employer) currently owns, operates and maintains a fleet of 100 x Sidetipper Wagons, consisting of 'Mark 1' and 'Mark 2' variants, that are permanently coupled together in sets of five (known as rakes) to deliver new aggregate (ballast) to rail worksites. Each rake has four identical wagons and a fifth that carries a diesel electrical generator, which in turn supplies hydraulic power packs on each wagon used to tip two independently controlled tipping boxes. Each generator can power up to a maximum of 10 wagons (2 rakes) in the event of generator failure. When offloading, particularly during dry ambient conditions, a significant plume of ballast dust, which contains Respirable Crystalline Silica (RCS) is observed. RCS is a known carcinogen, which after prolonged exposure can cause cancer of the lungs or other health conditions such as Silicosis. Therefore, it is the Employer’s foremost obligation to protect the wellbeing of its employees, contractors and lineside neighbours. To deliver on this obligation, and to comply with the Control of Substances Hazardous to Health Regulations 2002 and the Health & Safety at Work etc Act 1974, the Employer requires an engineering control in the form of a water-based dust suppression system (the solution) to be retrofitted

to the Sidetipper wagons to reduce RCS exposure. The existing Radio Controlled Handset system shall be modified to control the solution.

In addition, to combine workstreams and limit Wagon outage, the Employer requires the completion of further wagon modifications:

- Installation of 100 x Chute Proximity Switches.

- 50 x ‘Mark 1’ Sidetipper Handbrake Interlocks upgraded to ‘Mark 2’.