Playing to packed houses

IEC International Standards are always present in the limelight or backstage

By Morand Fachot

Millions of people watch films and plays or attend performances in cinemas, theatres or concert halls around the world every year. In addition to offering entertainment, enjoyment and artistic performance, these venues must ensure they provide the general public with a convenient, comfortable and safe environment in which to experience that enjoyment. This environment depends to a great extent on a multitude of technologies that rely on IEC International Standards.

Copenhagen escalators Escalators allow the efficient and speedy transport of thousands in public spaces

In comfort and splendour lies pleasure

In the past a central attraction of theatres, opera houses and subsequently cinemas, lay in their often majestic decor and a certain sense of luxury that drew large audiences keen to enjoy entertainment in a special environment.

In more recent times, convenience and technical advances have allowed a wider public to take advantage of facilities, increasing and extending this enjoyment significantly.

The quality and nature of lighting are central to performances. It’s vital that both decor and artists on the stage are properly lit. Light also plays also a central role in conveying atmosphere and mood. Stage lighting has become a highly complex craft that requires the participation of well-trained lighting designers and technicians. It is a craft that initially made great progress with the advent of electric lighting and then, much more recently, with the development of new types of lamps and lighting fixtures. HID (high intensity discharge) lamps such as metal halides are commonly used where a bright light output is required. They can be dimmed if required.

With advances in LED (light-emitting diode) technology, LED fixtures are being increasingly used in such venues. They present the advantages of having low power consumption, a long lifespan and of emitting little heat; they are also available in a wide range of colours. Lasers are also increasingly used for special effects.

IEC TC (Technical Committee) 34: Lamps and related equipment, and its four SCs (Subcommittees) develop international standards for lighting equipment such as is used in theatres and concert halls, including LED and metal halide lamps, lamp controlgear and more. SC 34D in particular has prepared an International Standard for floodlights and another one concerning luminaires for stage lighting, television and film studios (both outdoor and indoor).

IEC TC 76: Optical radiation safety and laser equipment, "prepares International Standards for equipment (including systems) incorporating lasers (and light emitting diodes) or intended only for use with lasers". The scope of this TC "includes the preparation of Standards applying limits (…) to human exposure to optical radiation (100 nm to 1 mm) from artificial sources", an important safety consideration in places where large crowds gather.

Sound and vision

Whether watching films, attending concerts or opera performances, sound quality is central to the overall enjoyment. IEC TC 100: Audio, video and multimedia systems and equipment, and its SCs (Subcommittees) have developed more than two dozen International Standards. The IEC 60268 series covers all aspects of sound system equipment, from microphones and headphones, to amplifiers, loudspeakers, connectors and other components.

For cinema, many studios and theatres have abandoned showing conventional photographic films and have converted to digital distribution of file-based content that uses the JPEG 2000 image coding system based on the ISO/IEC 15444 series of International Standards, prepared by ISO (International Organization for Standardization)/IEC JTC (Joint Technical Committee) 1/SC 29: Coding of audio, picture, multimedia and hypermedia information.

Convenience does no harm

As hundreds, sometimes thousands, of participants attend plays, shows and concerts, the smooth and safe flow of large numbers of people is vital. A wide range of equipment and systems has been designed with this in mind.

Elevators and escalators are prime movers of large numbers of people; they are not recent inventions. Elevators were first introduced nearly 160 years ago and the first electric elevator 30 years later. Escalators are more convenient for moving large numbers of people continuously but are not as efficient as elevators for moving smaller numbers of people intermittently.

Nowadays both elevators and escalators are increasingly designed to be highly energy efficient thanks to sensors which turn escalators on and off when not in operation, variable-frequency drives and numerous sensors that reduce the speed of the escalators when no one is using them, or energy-saving soft start systems that leave the speed of the escalator unchanged but reduce the power it consumes when fewer people are on it.

Ventilation, heating and cooling are also central to the comfort and wellbeing of spectators attending shows and concerts. IEC TCs and SCs that prepare International Standards for such systems and installations include: TC 17: Switchgear and controlgear, which prepares International Standards for elevators and escalators as well as for their assemblies, associated control and power equipment TC 47: Semiconductor devices, which develops International Standards for sensors and other systems SC 61D: Appliances for air-conditioning for heating, air-conditioning and ventilation systems in households and other applications.

Ensuring spectators' safety

Large crowds gathered in confined environments always present a certain number of safety issues. IEC TCs develop International Standards for a number of systems central to the safety of people in buildings and public places.

Fire and smoke alarm systems are central to safety in public buildings and are compulsory in most countries. Smoke detectors are the main fire alarm system. They can use different types of sensors and can be optical only, heat only, ionization only, or combine some or all of these types of sensors to provide better and quicker reaction.

A number of IEC TCs prepare International Standards for components used in detectors. IEC SC 47E: Discrete semiconductor devices, prepares International Standards for sensors used in smoke and fire alarms. Other IEC TCs include TC 20: Electric cables, which works on cables for fire alarm systems, and TC 79: Alarm and electronic security systems, which prepares IEC International Standards on EMC (Electromagnetic compatibility) immunity requirements for components of fire and security alarm systems.

Emergency lighting systems are essential for ensuring buildings are properly evacuated in case of emergencies such as fires. They are battery-powered safety devices that come on automatically when a building experiences a power outage. They are standard and required equipment in commercial, office and high-occupancy residential buildings. They are essential for providing light and directions and for signposting escape routes in the case of emergencies or fires, where there is darkness, in unlit or poorly-lit places or when there is smoke around.

As emergency lighting systems are safety-related products, their correct performance can only be assured by systematic testing and maintenance. Installing ATS (automatic test systems) avoids reliance on manual test procedures in conventional test systems that can fail to be carried out as a result of oversight or neglect. ATS can provide timely notification of failures or degradation of performance.

Copenhagen escalators Escalators allow the efficient and speedy transport of thousands in public spaces
Emergency Exit Emergency signs are essential to make public places safer
Laser Stage lighting now includes the use of LEDs and lasers to enhance visual effects (Photo: Edward Betts)