Average Rated Life – When you see average rated life as related to light bulbs it actually is the mean life of the lamps. The way the lighting manufactures test life is by using a large sample of light bulbs and the time when 50% have burned out and 50% are still working is Average Rated life
Ballast – An electrical device that is required to start and regulate voltage to fluorescent and HID light bulbs.
Base – The method that the light bulb uses to be connected to a fixture to be able to ignite.
Beam Angle – Is the angle in degrees that a flood light emits light and still has 50% of its intensity at any given distance. (Click to learn more about Beam Angle)
Bulb Shape/Style – Light bulbs are designed to meet specific shapes and styles that are used industry wide so that all manufacturers can provide products.
Color Rendering Index (CRI) – This number is how the industry rated how a light source shows correctness of colors (100 is the highest number). The higher the number the truer the color looks to your eye. (Learn more about CRI)
Color Temperature – Is the visual color that the light bulb produces. Rated in either number called kelvin (lower the number the warmer the light) or by descriptor of Warm (yellow white), Cool (crisp white) or Daylight (blue white)
Compact Fluorescent – Fluorescent light bulb designed to be used where a traditional incandescent light bulb is used. They can be self-ballasted so that they can screw into a standard fixture or non-ballasted plug in fluorescent light which requires a fixture with the ballast.
Diameter – The diameter (as related to light bulbs) is the measurement across the bulb at its thickest location.
Dimmable – The ability of the light bulb to be able to be dimmed. Not all light technologies are dimmable.
Duramax – Philips brand name for their long life incandescent light bulbs
Endura – Philips Lightings brand name for many of their LED light bulbs
Energy Star Qualified - ENERGY STAR is a U.S. Environmental Protection Agency (EPA) program to help consumers find energy efficient products. Products labeled with Energy Star have to be certified by a third party laboratory.
eW LED – The eW designation is a Philips lighting brand for some of their LED fixtures. This brand designates very energy efficient products.
Finish – Most light bulbs made out of glass have different finishes available. These finishes may include clear, frosted, white, natural light (blue), or many other colors.
Fluorescent Light – A light bulb that is coated with a fluorescent coating that will produce light when it is electrically charged. These lights require a ballast and starter to operate.
Germicidal Light – Light bulb that produces ultraviolet UVA light that has the capability of destroying bacteria.
Halogen Light – Is an incandescent light that has halogen used to shield the tungsten filament. It allows the light bulb to be higher efficiency and in many cases last longer. All halogen are fully dimmable.
High Intensity Discharge (HID) - These light bulbs produce light by using an electric arc between two electrodes incased in a arc tube. They have very high lumens to watt production (very intense light). These light bulbs require ballast and in some case a starter and capacitor. They are segmented into multiple classes; High Pressure Sodium, Low Pressure Sodium, Metal Halide and Mercury Vapor
High Pressure Sodium – A high intensity discharge lamp that uses sodium vapor to produce the arc that is creates the light. High pressure sodium produces a yellow light that has a low CRI in most cases.
Incandescent Light – Incandescent light is produced by an electric current passing through a filament (It one of the least efficient ways to produce light).
Infrared light (IR) – Infrared lights as related to lighting is mainly used as a heat lamp.
Kelvin – Kelvin is a numeric value placed on light bulbs that denotes the color of the light it produces. Kelvin in the lighting industry mainly ranges from 2700K to 6500K. The lower the kelvin rating the warmer the light produced (yellow white). The higher the kelvin rating the cooler the light produced (blue white).
Length (MOL) – The maximum overall length of the light bulb including the base.
LED Light (Light Emitting Diode) - A high efficiency lighting technology using a light emitting diode (LED) to produce the light.
Lumens – The method the lighting industry uses to measure the output of visible light a light bulb produces. The higher the lumen number is the higher the output by the light bulb.
Linear Fluorescent – These are fluorescent lights that are strait tubes of varying lengths and diameters
MasterColor – This term is used by Philips to denote there high CRI metal halide light bulbs
Metal Halide – Metal halide light bulbs produce light by igniting an arc in a vapor of mercury and metal halide gasses. The light produced with metal halide fixtures is white in color.
Probe Start Metal Halide – The probe start (switch start) metal halide light bulbs have a 3rd tungsten probe in the arc tube to start the light. The third probe is only used to ignite the light bulb by only having to strike an arc for a short distance. These lamps are less efficient than pulse start technology. (Probe start /switch start light bulbs are not interchangeable with pulse start)
Pulse Start Metal Halide – Pulse start light bulbs require an ignitor to start the arc in the lamp and only have two probes in the arc tube. The starter is required to send higher voltage through the arc tube to ignite the gas between the two probes. These lights tend to be more efficient and longer life than probe start technology. (Probe start /switch start light bulbs are not interchangeable with pulse start)
Rated Average Life – see “Average Rated Life”
Rough Service - Rough service light bulbs are designed to be used in high vibration environments. They have a tougher filament and more supports attached to the filament which resists failure due to vibration.
Socket - The socket is a term used to designate what type of system is used to connect the light bulb to the required electricity.
UV – Is the abbreviation for Ultra Violet. Ultraviolet light is non-visible light that can be used for specific tasks depending on the wave length. Ultra Violet wavelength is between 400 and 100 nanometers.
UVA - Ultraviolet A wavelength is between 400 and 315 nanometers. This light is commonly called black light (long wave.
UVC – Ultraviolet C wavelengths is between 315 and 280 nanometers. This light is used as a germicidal light (short wave). They are commonly used in water purification and air purification.
Voltage – Designates the rated voltage that the light bulb is designed to be used with.
Wattage - The amount of energy measured in watts that a light bulb uses over one hour.