HITTING THE HEIGHTS

FEBRUARY 2021 LIGHTING JOURNAL 35

High mast lighting

Maintaining high-mast lighting, such as that at sports grounds, brings with it quite specific challenges around access and safety. But it is also about recognising that, irrespective of the luminaire, mast and column maintenance needs to be an ongoing, long-term priority

By Darren Pearce and Chris Anderson

English cricket was, quite rightly, praised last year for eventually managing to salvage something of its Covid-19-ravaged season. Against the odds, and through the use of ‘bubbles’ and strict infection control protocols, we saw some thrilling, if still crowdless, Test, one-day and 20/20 matches against the West Indies, Pakistan and Australia.

Hopefully, with the rollout of vaccines during this year, 2021 will revert to being much more of a ‘normal’ cricket season, both at county and national level, and we can all finally return to our favourite grounds to enjoy day, day/night and nighttime matches.

Despite the financial transformation English cricket has gone through in recent decades, with TV money flooding in, central contracts for key players, new county structures and even the arrival of new formats such as ‘The Hundred’, when it comes to lighting you might be surprised to learn that many grounds are still yet to make the transition to LED.

What that means for firms like ours is that there is a requirement for ongoing maintenance at height every year, simply to keep the lighting levels up at grounds such as Edgbaston, Trent Bridge and others.

NEED FOR ONGOING MAINTENANCE

In fact, in some respects, when it comes to at-height maintenance, the LED transition debate is irrelevant anyway. People often think of LED switchovers as being some kind of panacea, meaning you will no longer have to maintain luminaires and you’re going to be able massively to cut down on ongoing maintenance bills as a result. At one level, if you’re just thinking about the luminaire, you’d be right.

But there is still an ongoing need to be maintaining the column and the mast that with cricket no exception. The lighting on a ground must continually meet sporting and broadcasting requirements.

Televised cricket, in particular, demands high illuminance levels. In fact, cricket – where you have a small, hard ball that moves fast, slow motion replays, the ‘snickometer’ and so on – is probably one of the most light-intensive sports there is; you are talking about 2,500 lux on the wicket. The lighting levels need to be really, really good, really consistent, and with a high level of uniformity.

We’ve already touched on the first maintenance priority, which matters however you’re doing anything – the mantra ‘if it is safe to do so’. A site-based risk assessment is an absolute prerequisite. You have to bear in mind, too, that rope access is governed by a different set of protocols because you’re climbing. Another way to access the headframe is through an external man rider.

The weather, clearly, is an important consideration. We often only get a small window of opportunity for maintenance, particularly at the start of the season before everything starts kicking off. Wind is an important factor, too.

goes with it, something that is, of course, even more important when you are talking about high masts. If a luminaire fails, it is going to have a detrimental effect on lighting levels; if a column or mast fails, especially one that is towering over a cricket ground, such as Edgbaston’s iconic ‘e’ headframe, it is a much more significant problem.

Back in 2011 we designed and installed Edgbaston’s floodlighting system as part of a £32m redevelopment project. Featuring a cantilevered design, each mast holds around 60 Abacus Challenger floodlights, which form the ‘e’, a light that is now very much part of the Edgbaston skyline.

It, like at a number of sports venues around the country, is a 50m-high static mast, where we need either to climb up to it to maintain it (if it is safe to do so) or use plant to access it. Other challenges in this context can be that many ageing assets, such as lattice towers, have many weld joints; many masts are also on unsafe foundations or have not had good planned maintenance in the past.

Clearly, many lighting engineers are familiar with at-height maintenance for street lighting, but what are some of the challenges associated with maintenance at this type of even higher level?

Floodlight maintenance involves checking that the luminaire is intact, secure and undamaged, with all associated electrical items being checked for security and any damage. The fixings, internal optics and visors must be inspected and cleaned to remove any build-up of dirt that may dim or adversely affect the luminaire output.

IMPORTANCE OF HIGH ILLUMINANCE LEVELS

On top of this, televised coverage is an increasingly important aspect of – and revenue stream for – many sports these days,

WEATHER AND PLANT ACCESS

We will be checking with the Met Office for wind speeds for the proposed day of the works. We can’t work if it is above a certain windspeed and, obviously, inclement weather issues have to be factored in. We try to avoid doing any of this kind of work during the depths of winter because you are more frequently exposed to high wind speeds.

Plant access can be another headache. How are we going to get the plant into these sites? Some of them are quite old grounds and housing has been built up around them over the centuries.

Trent Bridge, for example, was originally an old travelling inn or coaching house located on the edge of the city. The proprietor was into cricket and set up Nottinghamshire Cricket Club. The original ground was out in the middle of nowhere. Now, however, it is in the middle of Nottingham with two major road junctions either side; it is probably one of the most expensive areas for housing in Nottingham.

Headingley, in Yorkshire, is much the same. It has two major road junctions on the ground; you’ve got train lines at the back; you’ve got residential properties straight behind the ground; so it is a real hot potato in terms of physically being able to get an installation in to start with. Then, once you have got the plant in, especially if it needs to get on the pitch or pitch-side, you need to be sure to protect the pitch from

High mast lighting

damage, and so there is quite complex planning around that, too.

With the Edgbaston ‘e’, the bespoke headframe system comprises separate sections that have been bolted together. Each bolt requires inspection in order to keep the headframe intact, ensure the lanterns are in their correct place and that the public is safe.

We produce a report on the mast to include items such as the welded and bolted joints across the headframe and the mast itself, with any adjustments to be made where necessary. Mast inspection and reporting includes both the interior and exterior condition, with foundation, foundation bolts, shims and protective finishes all checked and accounted for.

HINGED MASTS

One solution we’re especially keen on, and in fact have pioneered, is hinged masts, whether base-hinged or tubular-hinged. Hinged masts are becoming a more common sight at ports and train stations as well as sports grounds. It stands to reason that if you are able to bring the luminaires to the ground to maintain them, that is going to be much easier than sending a man up to do the work. However, you do then of course need to ensure you are properly maintaining the working parts of the hinged mechanical structure.

We always revert back to the ILP’s PLG07 as our benchmark guidance, especially in terms of the frequency of inspections and when a structure is coming towards the end of its design life [1]. However, the ILP’s recent ATOMS guidance is also a valuable addition to your toolkit [2].

The older a column or mast is, it stands to reason the more it will need inspecting and being tested. Particularly when you have masts that have got to 25-30 years of age, you can have failures developing that are not visible to the naked eye, where the mast or headframe has become brittle from the inside. You can get condensation causing failures or welds breaking down.

Obviously, the transition to LED is likely to happen at cricket grounds eventually as much as anywhere else. But, to reiterate our point from earlier, that is not going to negate the need for ongoing duty of care and due diligence reheading and maintenance. Don’t neglect your columns and masts or look at LED and think ‘this is going to get rid of my maintenance issue’. If there is a column that it is sat on, that needs looking after as well. If you’re going to take on a rehead project, it is imperative you understand the implications of it; the ILP’s ATOMS guidance is, again, valuable in this context.

All checks must of course be done by a competent person, someone who is going to do a thorough and proper job and who knows what they’re looking at. It is about, first, making sure your lighting scheme is fit for purpose and doing what it needs to do. Then, second, regardless of what height the column or mast is, it is about making sure you have the processes and methodology in place to get up there safely, carry out a detailed inspection, and resolve any issues.

MAINTENANCE CONVERSATIONS

Particularly after the year we’ve just had, and with the economic effects of Covid-19 only beginning to be felt, a lot of people and organisations are going to feel under pressure financially; people are going to be looking to cut corners more and more going forward; they may no longer have the same budget for capital expenditure.

However, they may as a result have a bit more to spend on the maintenance budget, and be a bit more open to ‘make do and mend’ conversations. People may be thinking harder about how they can stretch their assets out a few more years.

So it is about all of us, as an industry and as individual lighting professionals, ensuring that money is being allocated in the best way; making sure the right things are being checked in the right way, whether we’re talking about at-height maintenance or just asset management more generally. Now is the time for the industry to be having these conversations, capturing these messages around the need, value and imperative of proper ongoing maintenance.

Darren Pearce is business development manager and Chris Anderson is UK sales director at Abacus Lighting

[1] PLG07 High masts for lighting and CCTV (2013 edition), the ILP, https://theilp.org.uk/publication/plg07-high-masts-for-lighting-and-cctv-2013-edition/; GN02 Lighting of televised sporting events, the ILP [2] GN22 Asset-management toolkit (minor structures), ATOMS, the ILP, https://theilp.org.uk/publication/guidance-note-22-asset-management-toolkit-minor-structures-atoms/