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LAMP STANDARDS

New federal guidelines for fluorescent lamps are defined in terms of efficacy and CRI (Coloring Rendering Index).

Efficacy is a measure of a lamp's energy efficiency. The efficacy of a lamp is determined by the amount of light output, measured in lumens, per watt of energy used. The term "efficacy" is used instead of "efficiency" because the units are lumens per watt (LPW), Efficiency has no units, but rather is expressed as a percentage.

CRI measures the effect that a lamp has on color appearance of an object. The higher the number, the more accurately the lamp renders the true color of an object, up to a maximum of 100. It should be noted that CRI is different from color temperature, such as warm or cool white.

By way of demonstration, here are some examples of Compliance and Non-compliance.

Example 1.

40 watt 4' fluorescent, or F40T12. CRI is usually about 62, below the minimum of 69. Light output of 3150 lumens at 46 watts (with a standard ballast). Its efficacy of 68,5 is below the minimum of 75.0. "Non-compliant".

Example 2.

output of 2850 lumens at 32 watts with an electronic ballast). Its efficacy of 89.1 is above the minimum of 75.0. "Compliant"

Small is better:

1" diameter T8 lamps from Ex.2 are more efficient than the 1.5" T12 lamps from Ex. 3.

Example 3.

34 watt 4' fluorescent, or F40T12/ES. CRI from 52-62, above the minimum of 45. Light output of 2800 lumens at 36 watts (with a standard ballast). Its efficacy 77.7 is above the minimum of 75.0 "Compliant"

It should be apparent from examples 2 and 3 that there are different levels of quality among compliant lamps. While both example lamps meet minimum standards, the T8 lamps are 15% more efficacious and offer significantly higher color rendering.

Incandescent lamps normally have a CRI of 100, so their standards are based on efficacy only. The new standards eliminate many popular "R" or "PAR" lamps, such as R30, R40, and PAR-38.

High-intensity discharge (HID) lamps are not affected by the 1995 phaseout. New HID standards will be developed by October 24, 1996, for implementation in 1999. The final EPACT standards for all other general service lamps will be established by October 24, 1998 for implementation in 2001.

32 watt 4' fluorescent, or F32T8. CRI from 75-85, above the minimum of 45. Light