Effective and successful performance within the operating room is enhanced by having lighting which does not cause visual, operational and environmental difficulties such as: glare, shadowing or visual stress.

The operating room environment requires a combination of satisfactory ambient lighting and effective direct and indirect task lighting. The ability to adjust these lighting levels and change their characteristics enables room staff to be more effective. Incorrect or poor lighting can impact on the patient, through poor performance and impaired effectiveness which may cause lengthened procedures through uncertainty, or even errors.

The wellbeing of the surgeon, the anesthetist and surgical team may also be adversely affected, while the quality and safety of the working environment will be impaired by poor ambient lighting.

According to studies, a very long time is usually spent for proper light adjustment. The lighting requirements for particular surgical specialties are so diverse that the individual requirements for each specialty must be taken into account when selecting room lighting.

The following points should be kept in mind during the design of the operating rooms and selecting the lighting system for the operating room:

Adjustability - the design of the lighting unit and how it can adapt to meet

individual requirements.

Brightness - the amount of light delivered by a source in order to illuminate a

specific surgical area.

Control - selection of a good design and an appropriate light source will help the systems integrate into the operating room environment. However, flexibility and adjustability in the lighting system (amount of light or spread of light, for example) will accommodate a wider range of tasks and activities.

Good color rendition is important in the operating rooms, intensive care rooms, examination rooms and in the treatments rooms.

In the operating rooms, a backup electric system should be available in the case of power failure.

There are typically three basic types of lamp used within an operating room environment: incandescent, gas discharge and Light Emitting Diodes (LED).

Incandescent and gas discharge lamps have traditionally been the main lamp type, utilizing halogen, tungsten, xenon and quartz. However, other types of lighting are now emerging onto the market in several forms, particularly LEDs.

1. Technical parameters.

The following parameters should be considered:

2. Central illuminance: This is the value of illuminance (LUX) at 1meter in the center of the light field.

3. Depth of illumination: The distance under the light-emitting area where the illumination reaches 20% of the central illuminance.

4. Light field diameter (50%): Diameter of light field where the illumination reaches 50% of the central iluminance.

5. Light field diameter (10%): Diameter of light field where the illumination reaches 10% of the central illuminance.

6. Color rendition index: The measure of the color spectrum of the light, made up from 9 measurements of each visible color.

7. Color temperature: Perceived coolness or warmth of light (measured in degrees Kelvin). Some LED lamps permit the ability to adjust the color temperature, which allows a surgical team to manipulate the light characteristics, and therefore facilitate tissue differentiation.

8. Radiant energy (Watt): Heat is produced from the light source in the form of infra-red radiation, which is felt by any person in the field of the radiation. This can provide an uncomfortable working environment not only for the surgeon, but the whole surgical team, as well as the patient. It may also hamper the operation by causing the wound tissue to dry out, especially during longer procedures.

The standard for operating room lighting:

IEC -60601-2-41