Even more important is proper lighting in the refinishing area. Improper lighting in this space adds to potential negative outcomes when a vehicle is in the full swing of production. And since refinishing occurs at the end of the production cycle, very close to the promised delivery date, any breakdown in the process can cause chaos. It also is important when working with color that the proper light source is present. So why take the risk?

Light is actually a mixture of different wavelengths that comprise what we may see as a "white light." If you remember back in science class in school, you probably projected a light source through a prism that broke the light source down into its included wavelengths. This was referred to as the spectrum of light and the colors that are displayed are always in the same order, but may vary in amounts based on the light source that was projected through the prism. In nature, we call this a rainbow when the sunlight shines through raindrops creating a natural spectrum. The wavelengths or colors in a spectrum are easily recalled by remembering the name, ROY G BIV. The spectrum colors are represented by Red Orange Yellow Green Blue Indigo Violet.

The Standards

Lighting is generally rated in three areas, Color Rendering Index as a percentage (CRI), Color Temperature in Kelvins (K) and Candle Power in Foot-Candles (FC). The comparison is based again on the standard for light, sunlight.

• Color Rendering Index — The color rendering index (CRI) identifies the degree of color shift objects undergo when illuminated by the light source. In simpler terms, the CRI expresses the degree to which a light source renders the true color based on the sunlight standard.

• Color Temperature — White light can have different "warmth effects." This can be quantitatively identified by the assigning of a color temperature, given in degrees Kelvin. For a practical example of color temperature, imagine when the color of a piece of steel is heated to various temperatures. A warm, reddish light is around 3,500 degrees Kelvin and a bluish tone indicates it is above 6,000 degrees Kelvin.

Natural sunlight color temperature is approximately 5,000 degrees Kelvin. This imitates the equatorial sunlight at noon. Noonday sunlight from northern portions of the earth has a larger amount of blue in the spectrum. This color temperature is closer to 7,500 degrees Kelvin.

• Candle Power — Candle power is the measure of how much light or its intensity that reaches the surface for proper illumination. The candle power is measured using foot candles (FC). Direct sunlight can be as high as 10,000 FC, whereas normal full daylight is at approximately 1,000 FC (see chart). It is important that enough light is present to adequately see what work is being performed, to see if proper coverage is achieved, and the effect of metallic and micas in the paint film.

Full spectrum lighting

Also make sure to check that the proper daylight corrected bulbs provide the appropriate color temperature of between 5,000 and 7,500 degrees Kelvin.

As to candle power — make sure there is a sufficient number of light fixtures in the entire refinishing department. This also includes the mixing room, prep stations and spray booths. During the purchasing of these manufactured units there are usually several options regarding the number and placement of the lights. Make sure to place a high priority to the number and type of light fixtures available.

In North America the "Big Three" in fluorescent tube manufacturing are General Electric, Sylvania and Philips. They all make, almost without exception, the same tubes, under different trade names although there are some notable exceptions. Smaller manufacturers include Durotest in the U.S. and Osram, which makes some tubes in North America and in Europe.

Maintenance and replacement program

Along with having the correct tubes installed, there are additional items with which you should be concerned. First and foremost is to implement a regularly scheduled maintenance and replacement program. The primary aim for any spray booth is to provide a clean and safe environment to refinish in. However, to produce consistent quality processes requires that a consistent maintenance and replacement program is implemented as well.

Often when I visit shops there are spray booths, prep stations and mixing rooms with burned-out lights in them, the lights are dirty and haven't been maintained at the level they should be. It's often stated that, "It's not my job," or, "We're too busy right now to worry about it." Then when asked, the technician can't even remember how long the bulbs have been burned out — "Maybe a year or so?"

It is very important to keep the light tubes clean as well as their protective lenses. You should clean the lens at least weekly and keep booth protective coating off them. Any colored overspray can affect the light output, too. The type of enclosed light fixture and the shop environment will determine how often the bulbs and reflectors need to be cleaned, but it's usually at least quarterly to semi-annually for most shops.

Keep in mind, as lights age they produce less and less output. Don't wait until the bulb burns out before replacement. The normal life span of fluorescent bulbs for proper output normally requires replacement yearly, so plan accordingly.

The little things count

Paying attention to the little details can make all the difference in the world for consistent production output at the expected quality levels. Little things like installing ceramic tiles in the prep stations and spray booth assists in having a good illumination at the floor level — and makes them easier to clean.

You may even consider a lift system as well in the needed areas — it's certainly impossible to expect proper coverage to the bottom of the rocker panel or other lower panels of a vehicle when the technician can't get the spray equipment in position to apply the products correctly. Finally, make sure the booth walls are properly reflective and not covered with paint overspray, which also makes the spray area brighter and more illuminated.

With properly installed and maintained equipment, a highly efficient refinishing environment should begin to eliminate many of the variables that have caused defects and process stoppages. These have often resulted in delays and missed target delivery dates that our customers have remarked on CSI surveys for years as unacceptable. These may be just small steps, but nevertheless they're steps in the right direction.