Equal and approved

In the specification of building services products it is common practice for specified products to be replaced at the procurement stage by alternative products that are deemed as ‘equal and approved’. With many items of plant it is possible to carry out a relatively simple comparison between the specified product and the proposed alternatives to establish whether the performance is acceptable.

With lighting, however, there are many factors to be considered, ranging from energy performance and light distribution through electrical safety and maintenance requirements to aesthetic appearance. Assessing alternatives, therefore, is a complex procedure – and accepting an unsuitable alternative can have serious consequences for the performance of the lighting.

Specifiers who fail to carry out the proper procedures can also leave themselves open to legal proceedings from the end-user if the lighting does not perform as expected. Unfortunately, there has been little clarity as to what exactly constitutes ‘proper procedures’ and specifiers are often under pressure from other members of the project team to make decisions they are not comfortable with.

To that end, the UK’s three leading lighting organisations – the Society of Light and Lighting, the Lighting Industry Federation and the Institution of Lighting Engineers – have joined together to produce guidelines for specifiers when dealing with ‘equal and approved’ luminaires. Their proposals also have the support of the Electrical Contractors’ Association.

Paul Ruffles of Lighting Design & Technology, a member of the team that drew up the proposals, puts the issue into perspective: “As designers we often get frustrated after spending months poring over catalogues with clients and architects to agree just the right luminaire for key spaces – only to have a contractor come along and bounce the project manager into accepting a cheaper alternative. While these have the same wattage lamps, they may not look the same or perform the same as the specified option,” he comments.

The proposals, which are explained in more detail further on, describe the key evaluative processes that need to be applied to proposed alternative luminaires to ensure that ‘equal and approved’ means just that.

Lighting designer Barrie Wilde has also been heavily involved in drawing up the proposals since the project began in August 2002. “The proposals are designed to provide a proper method of assessment that is understood by all parties,” he explains. “They are not designed to take away the manufacturers’ or contractors’ ability to negotiate but it is the job of the designer to secure the best interests of the client. And there has to be a clear audit trail to show that any alternative lighting has been thoroughly tested,” he continues.

The procurement process

Within the procurement phase of a project there is generally provision for contractors to offer ‘equal and approved’ or, perhaps more likely, to offer alternative luminaires via ‘value engineering’ exercises. These provisions are often encouraged by cost control consultants and contract management consultants as the alternative luminaires usually offer a cost reduction. This cost advantage will nearly always be beneficial to the contractor (declared or otherwise), and may also have some financial benefit to the client.

There are, of course, other reasons for offering alternatives; such as delivery dates, manufacturing delays and trading closure; but in a properly managed and programmed contract these would be abnormal circumstances. Undoubtedly, cost advantage is usually the driver for offering alternatives.

It is important to note that there is no suggestion that all alternative luminaires are inferior to those specified originally. “In some areas I specify a luminaire from one manufacturer but could easily have chosen a similar product from two or three others,” notes Paul Ruffles. “Here, if a contractor comes along with an alternative product that fulfils the specification in terms of appearance and performance, but is cheaper, then I am happy to accept this. The contractor is often better placed to test the market nearer to the time of supply than the designer who may be selecting products six or nine months before they need to be ordered,” he adds.

The process will be different for public bodies, who must comply with European procurement regulations.

Who is responsible?

The important factor is that the specifier responsible for the lighting design will generally have a responsibility for the effective and proper operation of the installed lighting systems – to deliver the intended lighting scheme both in aesthetic and technical senses. This includes compliance with the prescriptive quality and quantity parameters.

Failure to deliver a compliant lighting installation can result in litigation, so in many situations it will be incumbent upon the lighting designer to carry out rigorous interrogation of the alternative luminaires to ensure compliance with contracted obligations.

Here, there is the added problem that some obligations may have been set by other consultants such as the electrical engineer, architect or interior designer. Failure to consult with these parties in acceptance of alternatives may put the specifier or lighting designer in a vulnerable position with these parties even though the lighting objectives may be scheme compliant.

With some building services equipment, another option is for the designer to write a performance specification and then allow the contractor to select equipment that will provide that performance. Because of its highly visual nature, however, lighting specification is not generally that simple, as Barrie Wilde points out: “With lighting, the client and architect generally want to see the luminaires before installation so you end up with a schedule of luminaires. A specification based just on performance provides no guidance on the aesthetics of the fittings.”

All of which means that actual responsibilities, explicit or implicit, have to be understood by individual specifiers and/or lighting designers, and will be the subject of terms and contract conditions, forms of contract, agreed scope of works and deliverables etc. What is clear is that once a specifier or lighting designer enters into the evaluation and approval process of alternative luminaires they take on board both legal obligations and a financial commitment that may not be reimbursable!

An alternative approach is for the contractor to take on the responsibility for the performance of the proposed alternatives though, again, this may not be as simple as it sounds. “When an alternative luminaire is put forward by a contractor someone has to carry out checks that it conforms to the specified standards, that it does not affect the energy use calculations for Part L and that it provides the same task and room surface illuminance as the specified luminaire,” notes Paul Ruffles.

“If the original designer is to carry out these checks and calculations then someone will need to pay them as it is unlikely to be covered by their original appointment by the client. Alternatively the contractor will need to carry them out, which means they then take on certain aspects of the design responsibility for the project, which can be problematic if things subsequently go wrong,” he adds.

Ideally, then, the lighting designer will be in a position to carry out a thorough evaluation of any proposed alternatives and will be paid for the extra work involved. In these circumstances, there are a number of criteria that need to be applied when engaging in such an exercise.

• Professional fees – designers should only carry out a review of proposed alternatives if such reviews were part of their original professional agreement, or they have been given alternative reimbursement to carry out such a review. If no such arrangements have been made then the designer may, due to other constraints, be unwilling or unable to comment on any alternatives put forward. If the designer is commissioned by the contractor/manufacturer to carry out an assessment, clear professional separation between the designer’s original and the new commission must be maintained through a neutral and objective approach.
• Photometric equality – the designer should request full photometric characteristics for all alternative luminaires being offered, including the necessary polar curves or equivalent as well as detailed lighting calculations. The review must use the same parameters as the original calculations to ensure that the alternative luminaires still meet or exceed the scheme parameters and criteria.

It is important to note that submission of such calculations represents a legal undertaking by the submitting party, usually the contractor, and should be covered by suitable professional indemnity.

• Building Regulations, lighting energy consumption – the energy consumption of the specified luminaire and the proposed alternative must be compared and, when necessary, overall energy consumption of luminaires recalculated to confirm compliance with the Building Regulations – or with BSCP250 in the case of un-metered public lighting.
• Construction and robustness – confirming equal quality, durability and robustness may require submission of sample luminaires for both specified and alternative luminaires and any components. This is not to say that a luminaire with lesser construction and robustness will not be acceptable but does give a measure and yardstick against any declared ‘benefits’.
• Aesthetic acceptance – alternative luminaires must be considered both individually and in relation to other luminaires on the project to ensure aesthetic acceptability. This procedure should include an assessment of the luminaires in their lit appearance, rather than just a ‘touchy-feely’ exercise.

This exercise should be carried out with the architects, designers, client and other interested parties. In the case of exterior lighting this assessment should be carried out in conjunction with any fixing system and supports.

• Electrical equality – in projects dictating special characteristics for the luminaire, proposed alternatives should be assessed using the same criteria. Compatibility of components and systems should be checked to ensure safety – and that the performance of the original design is maintained (eg effect of changing control gear on lamp life). Power factor, di-electric characteristics, radio frequency interference, peak voltages and rupturing capacity of cables all need to be assessed along with many other electrical characteristics.
• Equality of other technical properties – proposed luminaires should be submitted with full specification and technical detail sheets to demonstrate compliance with British Standards or European standards. Where a proposed luminaire performance differs in any way from the specified luminaire a case should be submitted to support the alternative product and deal with the differences specifically.
• Maintenance – the ease and simplicity of maintenance should be considered as part of any assessment of alternative luminaires, which should meet any specific maintenance factor for the installation.
• Benefits – whether the benefits are financial, ease of installation or time saving, they should be declared with the submission and request for change of the specified luminaire.

Protecting interests

The concept of equal and approved is now so well established in the building services industry that we have to accept that it will continue. Therefore, it is important that lighting designers take appropriate measures to not only protect their own interests, but also the interests of the client. The processes described here provide a clear framework for a structured evaluation that addresses all of the issues and is easily understood by all members of the project team.

• For further information contact Paul Ruffles of the Society of Light and Lighting, tel: 01225 310022; e-mail info@ldandt.co.uk or Bernard Pratley of the Lighting Industry Federation, tel: 020 8772 9481, e-mail: bernard@lif.co.uk