Standards Development

Scope

This Published Document gives guidance and background information to specifiers and manufacturers of lighting columns on the use of BS EN 40-3-1 and BS EN 40-3-3, which specify the design of lighting columns. In particular, it gives guidance on the information which the specifier is required to give to the manufacturer to allow a suitable lighting column to be designed, such as the topography factor, site wind speed, site altitude and terrain category, which are used to determine the design wind pressure.

Purpose

Purpose of business case

What is the standard intended to achieve?

The EN 40 standard provides site-specific design guidance for individual lighting columns. This Published Document provides UK guidance on the application of EN 40 which can be applied to all columns in an administrative area. Amongst other things this will allow for the safe and cost-effective specification and design of lighting columns in the UK. Although the revision makes minor corrections to the design process, it also introduces advice on the design of connections. As such, the scope will be widened to include the addition of smart cities, IoT technologies and similar attachments to both existing and new column designs; changes that reflect the proposed changes to the scope of EN 40.

In the UK some columns have been installed that are not suitable for the location in which they are installed, and are therefore at risk of unexpected collapse in the worst case. For example, columns failed during storm Ciara due to incorrect design processes being used. Other dangers that this revision will help with include the avoidance of brackets and lanterns falling off columns that are a risk to the general public and property such as cars parked beneath the columns. (For information on Storm Ciara see: https://www.kier.co.uk/media/news-releases/kier-highways-teams-work-together-to-battle-storm-ciara.)

There are also cost savings for end-users of the PD due to the new design approaches being described. Each column designed in the UK normally takes around 30 minutes to design at a cost of £50 per hour. There are circa 8 million lighting columns in the country, and 5% per year on average are replaced which is a requirement of 400,000 individual column designs per year. This is 200,000 hours’ work equating to some £10 million per year cost to UK councils, without the use of PD 6547.

If we consider the use of PD 6547 in reference to the UK’s 150 administrative areas (as stipulated in a guidance table contained within the proposed Annex), each area would need between 5 and 10 different column designs for each area if using PD 6547, so approximately 1,500 column designs would cover the whole of the UK rather than 400,000 individual column designs needed without it. At 30 minutes and £50 per hour the overall cost of lighting column design to the UK is 1500 x 0.5 x 50 = £37,500: a saving of £10 million. In short, councils can list four or five different standard column options to suit their needs rather than individually design each column for each area by using the guidance in the proposed Annex table.

As well as the key aim of reducing design costs, another key aim is to reduce the contracting costs through rationalisation and resulting simplification of the supply and installation work. The PD is relied upon in most tender documents and is cited in Highways England’s TD 501 Road lighting design for street lighting columns (see file:///C:/Users/jonesg/Downloads/TD%20501%20Road%20lighting%20design-web%20(1).pdf). As such, it’s essential to get the design loading information provided in the current PD up to date, and to correct other small but important information: if lighting columns collapse they clearly have the potential to injure or kill someone (as evidenced by past accidents) and so carrying out designs before installation is essential and cannot be avoided.

In addition to the existing methods for calculating rooted foundations used in UK and the provision of standard sign sizes, the PD will introduce guidance on the addition of attachments to make smart columns. These changes will be included in EN 40 later when the current draft has been revised. BSI and the chair of the owning B/509/50 subcommittee are currently involved in a project to do just this with West Midlands 5G in association with the Humble Lamppost Project (European funded initiative). This will help leverage the use of lighting columns as the natural mounting position for small cell 5G roll out and help facilitate the rollout of autonomous vehicles on UK roads.

Who are the intended users? (Please give job roles and industry sectors)

- civil engineering and lighting consultants

- contractors - local authorities

- private companies (e.g. industrial, transport, infrastructure and housing developers)

- lighting equipment manufacturers

- test houses Why will users adopt the standard?

PD 6547 is cited in most lighting column design contracts issued by local authorities throughout the UK.

The load calculation methods provided in EN 40 provide a site-specific load check of individual columns which is not efficient for schemes with larger volumes of column; e.g., as supplied into a local authority, where there may be hundreds or thousands of columns purchased and installed and a buying policy involving standardisation is required. The method in PD 6547 provides this generic method for load calculations across different administrative regions.

PD 6547 is also being used to provide UK specific guidance above and beyond the information provided in EN 40 particularly on design checks for rooted foundations and the recommendations for selection of classes for signs and deflection limits that are able to be set for the UK market. The column deflection limits are set to levels that would prevent the general public being alarmed by the movement of the lighting column and prevent fear of collapse.

The specification of standard size signs to be included on the column ensures that the column can support a specific sign size without compromising the structural integrity of the column and therefore the safety of the general public. This has particular benefits in cases where unauthorised signs are added to columns in an uncontrolled manner by parties other than the highways authority or asset owner.

Why might they not use it?

No other similar industry documents in existence.