Beyond the Manual

Stage technology is highly advanced. Modern luminaires offer countless possibilities for lighting design, but anyone who works with them knows that the truly important data are often hard to access. Photometric values such as luminous flux, beam angle or illuminance are scattered across manuals, sometimes incomplete, rounded or presented in different formats. The situation is even more complicated for safety-critical information, which is often hidden in separate documents such as safety manuals.

What is the problem? The professionals on site, be it the lighting technician, the team leader, the head of lighting or the stage manager, have no time to fight their way through dozens of pages. The data must be accessible quickly, consistently and reliably, especially for a well-founded risk assessment. This document examines how providing photometric and safety-relevant data through an API (Application Programming Interface) could improve accessibility and thereby increase safety at events.

2.1Inconsistent data formats and data presentation

A major problem in current practice is the inconsistent presentation of measured values. Some manufacturers state illuminance, others luminous intensity or luminous flux. In addition, some providers supply a mixture of data from different photometric quantities, which makes comparison even harder and leaves professionals with the challenge of interpreting these different data consistently for their work. This inconsistency makes direct comparison difficult.

2.2Lack of standardisation

At present there is no uniform guideline for the provision of photometric data in the events sector. While the visible spectrum of roughly 380 to 780 nanometres is documented as standard, information about radiation beyond these limits is often missing, even though precisely this is relevant to photobiological risks¹. The German statutory accident insurers (Berufsgenossenschaften) define the range from 100 nanometres to 1 millimetre, since invisible radiation can also have harmful effects².

2.3Accuracy and completeness of the data

A further problem is the accuracy of the published data. Manufacturers round their data, mostly upwards, which makes precise calculations difficult. The raw measurement data are often confidential and are not disclosed. This leads to a situation in which professionals have to work with imprecise or incomplete values, which is particularly problematic for risk assessment.

2.4Spectral representation and scientific currency

The light spectrum of many stage luminaires is often given in user manuals only on a normalised scale on the Y axis, instead of taking the actual energy of the radiation into account³. Moreover, scientific research on the physiology of the eye is constantly evolving. For example, new findings about the ganglion cells of the retina show that existing safety assessments must be reviewed regularly⁴.

3.1Basic concept

An API (Application Programming Interface) could solve many of the problems described. Instead of searching manually through tables or PDFs for values, machines could retrieve and process the relevant data directly.

3.2Concrete benefits

Implementing a standardised API would offer several decisive advantages: lighting technicians could use a simple application to check the safety risks of a product within seconds, which would considerably increase the efficiency of their work. Data quality would improve substantially, since the exact raw measurement data could be queried in standardised form, leaving no room for interpretation or rounding errors. As far as safety is concerned, the evaluations could be carried out by software, which would minimise misjudgements. Furthermore, a uniform API would allow an objective comparison of luminaires from different manufacturers. Finally, standardised API formats give professionals the opportunity to create their own applications or spreadsheets with simple means, in order to analyse and present the data specifically for their individual requirements.

3.3Integration into existing systems

Integrating this API data into common visualisation and planning software such as Capture Sweden, Wysiwyg or Vectorworks would be particularly valuable. Safety-relevant information could then be taken into account as early as the planning phase.

4.1Real-time analysis during set-up

Let us imagine a typical situation at an event: the team is installing new stage lighting and a luminaire with unknown photometric properties is used. Instead of searching the entire manual, an application retrieves the photometric data specifically via the API and displays in real time an estimate of the light intensity and the potential risks, including UV or IR emissions.

4.2Collaborative safety assessment

If there is an error or an inconsistency in the risk assessment, team members who carry no direct responsibility can also access this information, share it and question it critically. Through collective review, this creates an additional measure of safety.

4.3Intuitive presentation of risks

Some luminaires already carry risk assessment graphics on their housings. These often show a light bulb on the left, an eye on the right and various risk classes in between. This presentation could be made considerably more intuitive by API-based applications, e.g. by integrating clearly recognisable symbols and colour codes, which were deliberately omitted from the design of the mostly black housings for aesthetic reasons.

5.1API specifications

For successful implementation it would be necessary to define an industry-wide standard for the API specification. It should cover the following aspects:

• Uniform data formats for photometric values.
• Standardised measurement methods and units.
• Complete spectral information, including invisible radiation.
• Mechanisms for versioning and updating

5.2Data security and accessibility

When developing an API, aspects of data security and accessibility must also be considered:

• Authentication and authorisation
• Availability and reliability
• Offline functionality for environments without an internet connection.
• Mechanisms for updating safety information

6.1Acceptance at industrial scale

One of the greatest challenges is establishing a standard at industry level. This would require cooperation between manufacturers, standardisation organisations and professional associations.

6.2Older devices and compatibility

For devices from older manufacturers without direct API support, central databases could be set up that retroactively provide the required information.

6.3Legal aspects

The provision of safety information is subject to legal frameworks, such as the European Machinery Directive (2006/42/EC)⁵, which already prescribes the provision of operating instructions. An addition to or adaptation of these directives could anchor the provision of API data in law.

Providing machine-readable data through an API is a long overdue step in the lighting industry. It would not only make the work of professionals easier but also improve safety in the workplace. Instead of working with outdated, imprecise or scattered information, lighting technicians could access exact, current and standardised data at any time.

The future of stage technology lies in digital networking and automation. A standardised API for photometric and safety-relevant data would be an important step in this direction.

The industry faces a decision: keep struggling with PDFs or finally take the step into the future? The answer is obvious.

1. International Commission on Illumination (CIE): standard definitions of the visible spectrum
2. TU Ilmenau
3. Physikalisch-Technische Bundesanstalt (PTB): recommendations on the measurement of optical radiation
4. Chronobiology International: study on the role of ganglion cells in light perception
5. EU Directive 2006/42/EC (Machinery Directive): obligation to provide operating instructions