Network Rail believes that all accidents and incidents are avoidable – as all its risks are known about somewhere in its business, either consciously or subconsciously. For this reason, it’s Safety Leadership and Culture Change (SL&CC) programme is promoting risk awareness, proactive involvement and open communications as part of a cultural change programme.
This programme shares the widely acknowledged belief that effective behavioural change will deliver significant site safety improvements, but perhaps not so well recognised is the potential for safety improvement through better project design. For example, in an HSE study (Bennett, 2004) it was found that in 43 per cent of the construction accidents studied, designers failed to address hazards that led to the accident.
One person who does understand how much designers can reduce the risks to maintenance and construction workers is Keith Miller, head of safety and sustainable development (Scotland and north east), Network Rail Infrastructure Projects, who is leading the SL&CC programme’s “Safety by Design” initiative. Although design might be considered a technical issue, Keith explains that the success of his initiative depends on the behaviours promoted by the SL&CC programme. He feels that risks to those working on rail infrastructure will only be effectively addressed if designers proactively seek to identify and manage such risks by engaging with those who will work on the assets they design.
Strategy for success
Keith is leading the promotion of the Safe by Design philosophy to improve design safety. This includes awareness training on the responsibilities laid down in the Construction (Design & Management) Regulations 2007 (CDM). This training is now being given to all those in Infrastructure Projects as training courses are being developed for each CDM role. Since February, investment panels have had to confirm that project design considers maintenance before granting investment authority, and examples of bad practice in this respect have been provided to route financial controllers. In March, Network Rail held a Safe by Design conference which was attended by 40 design suppliers.
Useful as these actions are, Keith recognises that a systematic programme is required to embed the required processes into the Network Rail design and procurement processes as well as ensuring designers’ commitment to the Safe by Design philosophy. In this Keith is supported by Paul Clark, head of engineering (central), Network Rail Infrastructure Projects. Paul has been actively involved in workshops to develop the Safe by Design programme which have identified issues to be addressed and the required actions. This has led to the development of a programme which was agreed by Network Rail’s Project Safety Leadership Group in April and addresses the following issues:
- Design risk assessment (DRA)
- Early focus on buildability and temporary works
- CDM roles and responsibilities
- Lessons learnt
- Procurement and programme
Paul offers examples of actions taken as a result of the workshops. To support DRAs, a project advice note has been issued on what a DRA should address on a typical project and a procedure is being trialled on the use of warning triangles on “Approved for Construction Drawings” to highlight work elements identified in the DRA. To share Lessons learnt, a collaboration website is being developed to share best practice in project design. Initially, those attending the workshops have been invited to populate this website, but the intention is that all Network Rail’s design suppliers will contribute.
A big difference
As well as undoubted safety benefits, Safe by Design offers significant cost savings at minimal, if any, initial cost. If done at the conceptual design stage, workforce safety improvements can be introduced at low cost, as shown by a graph of cost of change over a typical project lifecycle. Examples of design safety improvements that offer construction and maintenance cost savings include:
– Removing drilling, grinding and cutting processes;
– Off-site assembly;
– Increased use of mechanisation;
– Providing structures with scaffolding fixture points for future maintenance;
– Locating equipment cabinets greater than three metres from the line with no requirement to go “on or near the line”;
– Indentifying access route for heavy materials within a building at the design stage to enable use of mechanised plant;
– Using products such as lightweight TroTred troughing (the rail engineer issue 83 September 2011) to provide a combined cable route and safe cess.
Lee Parlett, heath and safety manager (Crossrail & Reading programme), Network Rail Infrastructure Projects, has experience of the benefits of design changes made early in the project lifecycle. He has been using CHAIR (Constructability Hazard Assessment Implication Review), a technique developed in Australia to reduce construction, maintenance, repair and demolition safety risks associated with design.
A recent CHAIR review was undertaken for an embankment that forms part of Crossrail’s new Heathrow flyover. This took two hours, involved 15 people and identified 30 risk reduction measures to be incorporated into the design including integrated reinforcing wall edge protection, lifting lugs for pre-fabricated panels, emergency egress and water run off mitigation. Lee’s belief in the Safe by Design philosophy was vindicated as it showed that, in his words, “with relatively little effort, it had really made a difference”.
Barriers to success
Designing for workforce safety is a legal requirement of the CDM Regulations. Unusually, it is a legal requirement that offers potentially large safety and cost benefits at minimal expense. However, although it would seem to be a “no brainer”, the concept is often not applied. Keith gives examples of an axle counter in the six foot, new S&C being installed without an access point, and lines converted to bi-directional working without additional track protection. Temporary works are often a problem. In a recent example, Keith saw a scaffold erected with its internal ledger bracings obstructing the working platform. Nevertheless, as Keith says: “I’ve got a huge amount of respect for Network Rail’s designers.They face the challenging task of designing safe rail infrastructure in accordance with the numerous applicable standards.”
Perhaps this partly indicates the problem, as hazard identification at design stage is unlikely to be effective if it is standard driven. Instead it requires an understanding of the construction and maintenance problems which may be unique to individual projects. Hence the requirement, at an early stage in the project, for designers to engage with construction and maintenance personnel. Another difficulty is that much design has to be discipline specific, whilst risk mitigation generally requires a multi-functional approach. For example, the track designers’ remit for replacement S&C may not include either permanent or temporary access.
As far as the CDM Regulations are concerned, the role of designer is not limited to technically qualified engineers. The HSE’s Industry Guidance for Designers shows how roles that are not normally thought of as designers can take decisions that have an impact on the health and safety of others. For example, sponsors might unduly limit available land, insist on a particular surface finish or limit maintenance access by specifying soft landscaping. Under the CDM Regulations, these are design decisions. However, those making such decisions might not be aware that they are adopting the CDM designer’s role.
A tale of three bridges
Balfour Beatty and Hyder Consulting provided the rail engineer with practical examples to illustrate how they have applied the Safe by Design philosophy. The new footbridge at Highbury and Islington, provided as part of the station remodelling, has an odd looking bump underneath its mid span. This is in fact a bolted splice to eliminate the requirement for delivery of a long bridge span. It involved minimal structural alterations and was simple to implement on site.
Andrew Dugdale, director for stations and depots, Hyder Consulting, explains that limited site access was identified early in Hyder’s design development review and incorporated into the design assurance log. As a result the final design had to address this constraint. The splice did, however, introduce additional risks of temporary erection and stability which was managed by appropriate instructions on the design drawings. Any potential working at height problems were eliminated by specifying connection of the splice before the bridge was lifted.
Keith Warburton, head of engineering for Balfour Beatty Rail Projects, explains how Balfour Beatty believes in going beyond compliance to challenge the “norm” of preliminary designs, employing a pro-active approach that minimises risks. He offers two specific examples of conventional rail civil engineering risks being largely eliminated by this innovative approach.
At Falmer Station, Balfour Beatty had the task of repairing the existing footbridge which presented risks of limited gauge clearance, contamination from blasting and inadequate access to structural members. It was decided to eliminate these risks by the novel solution of removing the structure from the railway and replacing it with a temporary footbridge. Detailed structural analysis was undertaken to specify the temporary work required and produce detailed drawings for lifting operations. This eliminated initially identified risks as work could then be done off-track. It also minimised possession requirements and the associated night-time working.
The Sutton Park line to the north of Birmingham, constructed in the late 1870s, provides a heavy freight route that avoids New Street. When Balfour Beatty was given the job of replacing a life-expired cattle arch, the original remit was demolition of the arch and its replacement with a new concrete or steel deck with new sill beams on repaired abutments. This demolition would have created risks from the excavations, working on track and at height, substructure stability, waste, noise and dust (and the problems that would cause with a Site of Special Scientific Interest nearby). There would also have been a large amount of waste material for disposal. Balfour Beatty’s alternative solution was to avoid the need for demolition by creating a new arch structure to support the original. This eliminated all of the initially identified risks and resulted in a smaller construction project which reduced the need for site storage and haulage.
From the past to the future
In 1916 Richard Maunsell, Chief Mechanical Engineer of the South East and Chatham Railway, gave his presidential address to the Institution of Locomotive Engineers on the subject of locomotive design and maintenance. He concluded by saying that “the engineer instinctively looks for the prominence of details which he knows should be accessible and he rightly regards as a monstrosity a machine which is lacking in this respect”. One hundred years later, this statement applies equally to new rail infrastructure with poor maintenance access.
Just last month at the rail engineer technical seminars at Infrarail, almost 100 years after Richard Maunsell’s comment, Simon Kirby presented Network Rail’s future strategy for project delivery. In doing so, he declared his belief that “getting contractors’ early input to design has to be the right thing from a safety point of view”. He felt this to be just one of the benefits of Network Rail’s new approach to supplier engagement and project delivery, for which cultural change is essential. Thus the Design for Safety initiative is an integral part of the changes, to which Network Rail are committed. For this reason alone its success would seem to be guaranteed.
The assistance of Network Rail, Hyder Consulting and Balfour Beatty in the preparation of this article is gratefully acknowledged. Project design safety guidance is available from the websites below: