Safety solutions provided at one of Europe’s most prestigious stations by ph Water Technologies.
How the installation of ground level manway entry systems reduced the H&S risk associated with water storage tank maintenance & inspections at one of Britains most famous railway stations & the terminus for the Eurostar services through the Channel Tunnel.
The HSE’s emphasis on preventing death, injury and ill-health in the UK workplace has been paramount in saving lives and reducing accidents. The risks surrounding working inside confined spaces such as water storage tanks are significant and can be an unknowing killer. In January 2013 the HSE ran a campaign on the dangers of working at height which featured some excellent advice on how to avoid them. Their report highlighted the real dangers of working at height, which along with confined spaces is an issue when accessing large tanks with top access manways.
The law regarding confined spaces and working at height is clear.
- The Confined Spaces Regulation 1997 – Other legislation may apply, depending on where the confined space is situated or on the task being carried out
- The Management of Health and Safety at Work Regulations 1999
- The Personal Protection Equipment Regulations 2002 and Personal Protective Equipment (Health and Safety Regulations 1992)
The dangers of confined spaces and working at height are numerous
- Harmful gas, fumes or vapours
- Fire and explosions
- Slip trips and falls
- falling from height
In recent years the benefits of ground-level access manways have become notable as the HSE has brought prosecutions against companies that failed to provide adequate health and safety training for employees working in enclosed spaces. These prosecutions bring sharply into focus the drawbacks of ‘top-down’ tank access.
Installation of ground level manway entry systems
As the incumbent Water Treatment specialist at one of Europe’s busiest and most prestigious stations, Ph Water Technologies were contracted to install “ground level manway entry systems” to allow safe ingress & egress to 6 large cold water storage tanks.
- CWST 1a – 42000 litres
- CWST 1b – 42000 litres
- CWST 2a – 30,000 litres
- CWST 2b – 30,000 litres
- CWST 3a – 9000 litres
- CWST 3b – 18000 litres
By installing ground-level access manways it greatly reduces the H&S risk and provides the ability for operators and maintenance staff inspect and undertake planned maintain, as well ensuring ease of access for emergency staff to treat and evacuate individuals from a tank, at ground level should it ever be required.
The low-level manway maximises time and efficiency by reducing the use of harnesses and access steps and minimises any further injuries and falls if operations personnel are overcome by fumes within a tank. Manway also allows for stretcher access and extraction.
Site specific RAMS, were prepared which included a confined space emergency escape plan and testing the atmosphere inside tank by suspending a calibrated gas monitor into the tanks. Each integrated access hatch was to be bolted, flanged and completely removable to facilitate safe access.
As one of the tanks had been previously been re-lined, careful abrasion, cutting and removal of flexible resin/ polyurethane coating was necessary to ensure that the old lining was not compromised.
In order not to invalidate the 10 year warranty the internal surfaces were manually prepared to remove the existing coatings and to provide a surface profile of 0.75mm to accept the new coating. All joints were stripe coated with a base coat (Grey) of DWPU to build up the thickness in these critical areas before applying to all internal surfaces at a nominal thickness of 400 micron.
The above was repeated with a top coat (blue) of DWPU applied to all internal surfaces. When the coating had cured, each tank was disinfected to PD855468:2015 before being re-instated to normal operation.
The whole project duration was estimated at 20 days and due to the bypass configuration all works were carried out during normal working hours without any interruption to the stations domestic water services.
Ph Water Technologies can also custom fabricate hatches to any required size for steel sectional Braithwaite tanks