In general, the same lighting design principles apply to both residential and commercial bathroom interiors.

* Do not install a downlight directly over the bathroom sink, as it will create strong shadows on the viewer's face.

* If you must install a downlight directly over the bathroom sink, or if there is one already installed there, use a standard household "A" lamp rather than a direction R or PAR lamp. The shadows will be softer.

* Do not rely on recessed lighting above a mirror to give good lighting for shaving and makeup.

* Use diffuse or strong indirect lighting to get shadow-free vanity light. Favor side lighting at the mirror to provide strong and useful frontal light.

* Consider the width and height of the mirror before selecting the vanity lighting, and its placement.

* When facing a marrow mirror, decorative fixtures with clear finishes or bare bulbs may produce too much glare.

* When facing a wide mirror, consider what the viewer sees in the opposite wall; if you have a bright light source located on the opposite wall, it will flare into the viewer's eyes as he looks into the mirror.

* Select decorative lighting for the scale of the vanity and the mirror.

* Consider lighting the toilet area with a separate light source for reading. Install a localized dimmer near the paper holder to control the brightness of that light.

* For an enclosed toilet area, consider a wall sconce on one of the side walls rather than a downlight.

* Organize the switches as you enter the bathroom. For example, many would consider general illumination, sink, vanity/dressing, and shower controls to be in a logical order.

* Use no more than a three-gang switch box at the bathroom entrance. More than three switches look ugly on a wall. They take up wall space, and they make it difficult for the user to remember which switch goes with which light.

* Provide a light source in the bathroom that also can be used for a night-light.

* Avoid dropped plastic lenses on recessed fixtures in bathrooms. The white plastic lens is too bright and takes away from the bathroom's appearance.

* Always place a recessed downlight in the tub area and consider one with a regressed Fresnel lens rather than a white lens, because it spreads light more evenly.

* Consider an automatic switch that turns the light on and off as you open and shut the door.

* Place all electrical switches away from tubs and showers. Install only ground-fault circuit interrupter (GFCI) electrical receptacles (even if you are not remodeling, update to GFCI receptacles now).

* Use general lighting throughout the bath, and install task lighting in vanity and grooming areas. Do not overlook storage areas, tubs, or showers in your lighting plan.

* Consider using both incandescent and fluorescent light sources in the vanity/makeup area, on a separate circuit if a professional female occupies the home. She can apply makeup under the same amount of lighting under which others will be viewing her: fluorescent for the office and incandescent for restaurants, nightclubs, or at home.

Author's note: This article was based on a presentation given by five Boston-area lighting designers at Lightfair International. In addition to the author, other presenters were Peter Coxe, of Peter Coxe Assoc., Marblehead, Michael Eberly, Chimera Design Lighting, Boston, Jeffery Sladen, Berg Howland Assoc., Cambridge, and Susan Frenette, Lightspace Design, Amherst, N.H.

ATHERTON, a residential interior and lighting designer, is frequent contributor of lighting topics to Electrical Contractor. She is also the publisher of Light-Connections, where a different version of this article first appeared. She can be reached at Drew Atherton Interiors, Boston, or by calling (781) 934-2143, ext. 31, or e-mail at drew@light-connections.com.