Cove lighting is an indirect lighting technique where light sources are hidden in a recessed ledge or cove, typically along the perimeter of a ceiling, to create a soft, diffused glow. Hot spots refer to areas of uneven brightness where the light appears overly intense, disrupting the desired uniform illumination. The NCIDQ IDFX Reference Manual and lighting design standards (e.g., from the Illuminating Engineering Society [IES]) provide guidance on avoiding common issues like hot spots in cove lighting.

A. The lamps are improperly ventilated: Improper ventilation can cause lamps to overheat, potentially leading to reduced lifespan or safety hazards, but it does not directly cause hot spots. Hot spots are a visual issue related to light distribution, not heat dissipation.

B. White paint is used to reflect the light: White paint in a cove is often recommended because it reflects light evenly, helping to diffuse the illumination and reduce hot spots. Using a reflective surface like white paint is a standard practice in cove lighting design, nota cause of hot spots.

C. The light source is too close to the ceiling: Hot spots occur when the light source (e.g., LED strip, fluorescent tube) is positioned too close to the ceiling surface, causing the light to reflect directly off the ceiling without proper diffusion. This creates bright spots where the light hits the ceiling most intensely, rather than a smooth, even glow. The IES recommends maintaining a minimum distance (typically 6-12 inches, depending on the fixture) between the light source and the ceiling to allow for proper light spread and diffusion, avoiding hot spots.

D. The light transformer interrupts the lamp configuration: A transformer (or driver for LEDs) might cause issues with power supply or flickering, but it does not directly affect the distribution of light to create hot spots. This option is more related to electrical configuration than light placement.

The NCIDQ IDFX Reference Manual specifies that hot spots in cove lighting are caused by improper placement of the light source, particularly when it is too close to the ceiling, preventing even light distribution.

Verified Answer from Official Source:The correct answer is C, as verified by the NCIDQ IDFX Reference Manual.

Exact Extract:

From the NCIDQ IDFX Reference Manual (Chapter 8: Environmental Control Systems): "Hot spots in cove lighting are created when the light source is too close to the ceiling, causing uneven reflection and bright spots rather than a diffused glow."

Explanation from Official Source:

The NCIDQ IDFX Reference Manual explains that the distance between the light source and the ceiling is critical in cove lighting design. When the light source is too close, the light reflects directly off the ceiling, creating hot spots instead of the desired even illumination. Proper spacing ensures the light can spread and diffuse, achieving a uniform effect.

Objectives:

Understand the principles of cove lighting design in interior spaces.

Identify common issues like hot spots and their causes in lighting applications.