Mercury Use in Lighting

Mercury is used in a variety of light bulbs, from fluorescent tubes to car headlights to neon signage.  Although mercury is hazardous to human health and the environment, it is useful in lighting because it contributes to the bulbs’ efficient operation and life expectancy.  Fluorescent and other mercury-added bulbs are generally more energy efficient and last longer than incandescent and other equivalent forms of lighting.  While the bulbs are being used, the mercury within them poses no health risk.

Purpose of Briefing Paper

The purpose of this Briefing Paper is to provide information on the different types of mercury light bulbs in use, as well as information on the amount of mercury used in them.  Because the lighting industry uses the term lamp rather than bulb, this Briefing Paper hereafter follows the industry’s convention and uses the word lamp.

This Paper relies primarily on data obtained from the Interstate Mercury Education & Reduction Clearinghouse (IMERC)ⁱ  Mercury-Added Products Databaseⁱⁱ to summarize the use of mercury in lighting.  The IMERC database contains information on the amount and purpose of mercury in products submitted by, or on behalf of, product manufacturers in compliance with laws in the states of Connecticut, Maine, New Hampshire, New York, Rhode Island, and Vermont beginning in 2001.

The data may help state and local governments and non-profit organizations target their lamp recycling promotion efforts.

While it is beyond the scope of this Briefing Paper to estimate how much mercury enters the environment from improper disposal of lamps, readers can make their own, crude estimates by applying lamp recycling rates to the data provided in Table 1 (total amount of mercury sold in lamps in 2001 and 2004).  It is important to note, however, that mercury is contained in a powder form and as a vapor in fluorescent lamps, and it adheres to the glass walls of lamps over time.  Scientists are uncertain how much of this mercury is released when a lamp breaks.   Several references listed at the end of this Paper provide estimates on the percent of mercury that is released from broken fluorescent lamps.

Mercury Lamp Disposal

At this time technology is not available to make general purpose, energy efficient light bulbs without mercury, although non-mercury bulbs have been recently developed for specific purposes, such as car headlights or store display lighting.   Mercury-added bulbs should therefore be used, but managed as a hazardous waste, or else recycled, at the end of their useful life.  Each state has specific regulations for businesses and homeowners regarding recycling or hazardous waste disposal of mercury-added bulbs.  Visit www.newmoa.org/prevention/mercury/lamprecycle/requirements.cfm for state-specific recycling and disposal requirements in the northeast states, or www.almr.org/ for states outside of the region.  Homeowners and businesses can also call their state environmental agencies’ hazardous waste bureaus for more information.

Mercury Lamp Types:

This Briefing Paper divides mercury lamps into the following categories:

• fluorescent
• compact fluorescent
• high intensity discharge (includes metal halide, ceramic metal halide, high pressure sodium, and mercury vapor)
• mercury short arc (includes mercury and mercury xenon short arc lamps),  
• capillary
• neon

Each category is briefly described below.

Fluorescent  A fluorescent lamp is an electrical discharge lamp that operates at a very low gas pressure.  It produces light when electric current passes between two electrodes (also called cathodes) in a tube filled with low-pressure mercury vapor and inert gases such as argon and krypton.  The electric current excites the mercury vapor in the tube, generating radiant energy, primarily in the ultraviolet (UV) range.  The energy causes a phosphor coating on the inside of the tube to “fluoresce,” converting the UV light into visible light.  Mercury is present in the lamp in both the phosphor powder and in the vapor. Figure 1 illustrates the components of a fluorescent tube and their purpose.

Fluorescent lamps require a ballast, which is a device used to provide, and control, the voltage in the lamp, as well as stabilize the current in the circuit.

Fluorescent lamps are more efficient than incandescent light bulbs of an equivalent brightness because more of the energy input is converted to usable light and less is converted to heat.  They also have a longer lamp life.

  
Figure 1: How a fluorescent lamp works
Image courtesy Northeast Lamp Recycling, Inc.

Typical types of fluorescent lamps include:

• linear (straight-shaped), U-tube (bent) and circline (circular-shaped)
• bug “zappers”
• high output
• tanning lamps
• black light
• germicidal
• cold cathode

Changing the composition of the phosphor powder inside fluorescent tubes changes the spectrum of light given off.  Tanning lamps use a phosphor composition that emits primarily UV light, type A (non-visible light that can cause damage to the skin), with a small amount of UV light, type B.  Black lights use a phosphor composition that converts the short-wave UV within the tube to long-wave UV rather than to visible light. Germicidal lamps use no phosphor powder and their tubes are made of fused quartz that is transparent to short-wave UV.  The UV emitted kills germs and ionizes oxygen to ozone (used for sterilization of air or water). See figures 2 and 3 for pictures of germicidal and tanning lamps.

                    
Figure 2: Germicidal Lamp               Figure 3:Tanning lamps                 Figure 4: U-tube and Circlinelamps

Photos courtesy of Northeast Lamp Recycling, Inc.

Linear fluorescent, U-tube, and circline lamps are used for general illumination purposes.  They are widely used in commercial buildings, schools, industrial facilities and hospitals. Figure 4 shows typical U-tube and circline lamps.

High output fluorescent lamps (HO) are used in warehouses, industrial facilities and storage areas where bright lighting is necessary.  HO lamps are also used for outdoor lighting, because of their lower starting temperature, and as grow lamps.

Cold cathode lamps are small diameter, fluorescent tubes that are used for backlighting in liquid crystal displays (LCDs) on a wide range of electronic equipment, including computers, flat screen TVs, cameras, camcorders, cash registers, digital projectors, copiers and fax machines; they are also used for backlighting instrument panels and entertainment systems in cars.

Cold cathode fluorescent tubes operate at a much higher voltage than conventional fluorescent lamps, which eliminates the need for heating the electrodes (hence the name cold cathode) and increases the efficiency of the lamp 10 to 30 percent.  They can be made of different colors, have high brightness, and long life.

Fluorescent lamps contain a wide range of mercury, from greater than 0 up to 100 milligrams (mg).  According to the National Electrical Manufacturers Association (NEMA), about half contain greater than 5 up to 10 mg of mercury; while a quarter contain greater than 10 to 50 mg. (see Table 2)  

Compact fluorescent lamps (CFL) use the same basic technology as linear fluorescent lamps, but are folded or spiralled in order to more approximate the physical volume of an incandescent bulb.  Screw based CFLs typically use “premium” phosphors for good color, come with an integral ballast, and can be installed in nearly any table lamp or lighting fixture that accepts an incandescent bulb.  Residential use of these bulbs is growing because of their energy efficiency and long life.  Pin-based CFLs do not employ integral ballasts and are designed to be used in fixtures that have a separate ballast.  Both screw based and pin based types (designed to be plugged in to a special lamp holder) are also used in commercial buildings. Figure 5 shows a picture of spiralled CFLs.

Individual CFLs generally contain less than 10 mg of mercury, with a significant portion (two-thirds) containing less than 5 mg (see Table 2).  A small percentage of CFLs contains between 10 and 50 mg of mercury.

Figure 5: Compact fluorescent lamps Photo courtesy: Osram Sylvania and GE Lighting

High Intensity Discharge (HID) is the term commonly used for several types of lamps including metal halide, mercury vapor and high pressure sodium.

HID lamps operate similarly to fluorescent lamps in that an arc is established between two electrodes in a gas-filled tube, causing a metallic vapor to produce radiant energy.  HID lamps do not require phosphor powder, however, because a combination of factors shifts most of the energy produced to the visible range.  In addition, the electrodes are much closer together than in most fluorescent lamps, and under operating conditions the total gas pressure in the lamp is relatively high.  This generates extremely high temperatures in the tube, causing the metallic elements and other chemicals in the lamp to vaporize and generate visible radiant energy. 

The names of the HID lamps (i.e., metal halide, mercury vapor and high pressure sodium) refer to the elements that are added to the gases (generally xenon or argon and mercury) in the arc stream.  Each element type causes the lamp to have somewhat different color characteristics and overall lamp efficiency.

HID lamps have very long life.  Some emit far more lumens per fixture than typical fluorescent lights.  Like fluorescent lamps, HID sources operate from ballasts specifically designed for the lamps type and wattage being used.  In addition, HID lamps require a warm-up period to achieve full light output.  Even a momentary loss of power can cause the system to “restrike” and have to warm up again—a process that can take several minutes.

Metal Halide (MH) lamps use metal halides such as sodium iodide in the arc tubes, which produce light in most regions of the spectrum.  They provide high efficacy, excellent color rendition, long service life, and good lumen maintenance, and are commonly used in stadiums, warehouses, and any industrial setting where distinguishing colors is important.  They are also used for the bright blue-tinted car headlights and for aquarium lighting.  Low wattage MH lamps are available and have become popular in department stores, grocery stores, and many other applications where light quality is important. See figure 6 for a picture of a typical metal halide lamp.

Of all the mercury lamps, MH lamps should especially be considered a complete system of lamp, ballast, ignitor, fixture, and controls.  The lamp is finely tuned with precise doses of chemicals and carefully engineered dimensions.

The amount of mercury used in individual MH lamps ranges from more than 10 mg to 1,000 mg, depending on power level.   According to NEMA, about one-third contain greater than 100 to 1,000 mg of mercury (see Table 2).

Figure 6: Metal Halide Lamp
Courtesy: Northeast Lamp Recycling, Inc.

Ceramic Metal Halide (CMH) lamps were recently introduced to provide a high quality, energy efficient, alternative to incandescent and halogen light sources.  Many are designed to be optically equivalent to the halogen sources they were designed to replace.  They are used for “accent lighting,” retail lighting, and are useful in high volume spaces, with ceiling heights 14-30 feet (as an alternative to incandescent, halogen, or metal halide lamps)   The arc tube is made of ceramic.   

CMH lamps provide better light quality, better lumen maintenance, and better color consistency than MH lamps at a lower cost.

CMH lamps contain less mercury than MH lamps.  The majority contain from greater than 5 mg to 50 mg of mercury (see Table 2).

High Pressure Sodium (HPS) lamps are the most efficient light source commercially available, but tend to look yellow and provide poor color rendition.  HPS lamps were developed in 1968 as energy-efficient sources for exterior, security and industrial lighting applications and are particularly prevalent in street lighting.  Standard HPS lamps produce a golden (yellow/orange) white light when they reach full brightness.  Because of their poor color-rendering their use is limited to outdoor and industrial applications where high efficacy and long life are priorities. Figure 7 shows typical HPS lamps.

HPS lamps generally contain from more than 10 to 50 mg of mercury.  A very small percentage contains more than 50 mg of mercury (see Table 2).

                                   
Figure 7: High pressure sodium lamps                                Figure 8: Mercury Vapor Lamps
Photo courtesy: Osram Sylvania                                          Photo courtesy: Osram Sylvania

Mercury Vapor lighting is the oldest HID technology.  The mercury arc produces a bluish light that renders colors poorly.  Therefore, most mercury vapor lamps have a phosphor coating that alters the color temperature and improves color rendering to some extent.  Metal halide lamps have largely superseded the use of this lamp. Figure 8 shows some mercury vapor lamps on the market today.

Mercury vapor lamps have a lower light output and are the least efficient members of the HID family.  They were developed to overcome problems with fluorescent lamps for outdoor use, but are less efficient than fluorescents.  Mercury vapor lamps are primarily used in industrial applications and outdoor lighting (i.e., security, roadway, and sports arenas) because of their low cost and long life (16,000 to 24,000 hours).  According to NEMA, these lamps represent a diminishing market, and their use will continue to decline because their ballasts have been banned under the Energy Policy Act of 2005.

According to NEMA, Mercury vapor lamps generally contain between 10 and 100 mg of mercury; however a small portion contains greater than 100 mg (see Table 2).

Mercury Short-Arc lamps are spherical or slightly oblong quartz bulbs with two electrodes penetrating far into the bulb so that they are only a few millimeters apart.  The bulb is filled with argon and mercury vapor at low pressure.  Wattage can range from under a hundred watts to a few kilowatts.  With the small arc size and high power, the arc is extremely intense.   Mercury short arc lamps are used for very special applications, such as search lights, specialized medical equipment, photochemistry, UV curing and spectroscopy. Figure 9 shows examples of mercury short-arc lamps.

These lamps contain greater amounts of mercury, typically between 100 mg and 1000 mg.  Nearly a quarter contain more than 1,000 mg (see Table 2).

Figure 9: Mercury Short-Arc Metal Halide Lamp
Courtesy: Northeast Lamp Recycling, Inc.

Mercury Xenon Short-arc lamps operate similarly to mercury short-arc lamps except that they contain a mixture of xenon and mercury vapor.  They do not require as long a warm up period, however, and have better color rendering.  They are used in industrial applications. Figure 10 shows some example mercury xenon lamps.

      
Figure 10 : Mercury Xenon Lamp              Figure 11:  Mercury Capillary Lamp
                           Courtesy: Northeast Lamp Recycling, Inc.

Mercury Capillary lamps provide an intense source of radiant energy from the ultraviolet through the near infrared range.  These lamps require no warming up period for starting or restarting and reach near full brightness within seconds.  They come in a variety of arc length, radiant power, and mounting methods and are used in industrial settings (i.e., for printed circuit boards), for UV curing, and for graphic arts.  UV curing is widely used in silkscreening, CD/DVD printing and replication, medical manufacturing, bottle/cup decorating and converting/coating applications. Figure 11 shows examples of mercury capillary lamps.

These very specialized lamps contain 100 to 1,000 mg of mercury.

Neon Lights

Neon lights are gas discharge bulbs that commonly contain neon, krypton, and argon gasses (also called noble gasses) at low pressure.  Like fluorescent bulbs, each end of a neon light contains metal electrodes.  Electrical current passing through the electrodes ionizes the neon, and other gases, causing them to emit visible light.  Neon emits red light; other gases emit other colors.  For example, argon emits lavender and helium emits orange-white.  The color of a “neon light” depends on the mixture of gases, the color of the glass, and other characteristics of the bulbs.

Although the term “neon light” refers to all gas discharge bulbs using noble gases, regardless of the lamp color, only the red bulbs are true neon lights, (i.e., use neon).  Red neon lights do not contain mercury.   Almost every other color of “neon light” is produced using argon, mercury and phosphor, in addition to other noble gases.

The neon light industry is a cottage industry.  Artisans make each lamp individually in small workshops.  The vast number of neon light manufacturers has made it difficult for IMERC to identify and reach out to them.  For this reason the IMERC-member states have not yet received Notifications from most of the manufacturers of neon lights.

Neon lights are estimated to contain approximately 250 to 600 mg of mercury per bulb, depending on the manufacturer’s preference.  A new product developed by the manufacturer Eurocom Inc. can reduce the amount of mercury typically used by 80 percent.[1]

Total Mercury Use in Lamps

Table 1 presents information on the total amount of mercury sold in lamps in calendar years 2001 and 2004, as reported to the IMERC-member states.  Lamp manufacturers, also referred to as the “original equipment manufacturers” (OEM) reported this data. Data reported by the manufacturers of final products containing lamps, such as electronic equipment or recreational vehicles, are not provided because of the ubiquitous use of lamps in larger products.  See the Appendix for the list of lamp OEMs reporting to the IMERC-member states.

A number of important caveats must be considered when reviewing the data summarized in this Table:

• The information underestimates the total amount of mercury reported for this category of products.  The states participating in IMERC continuously receive new Product Notification Forms from mercury-added product manufacturers.  The data presented in this Briefing Paper therefore underestimate the total amount of mercury sold in these products in the U.S. in 2001.

• The data presented summarize mercury in lamps sold nationwide in the U.S. in calendar year 2001 and 2004.   It does not include products that were sold prior to January 1, 2001.

• Reported data only includes mercury that is used in the product, and does not include mercury emitted during mining and/or manufacturing.

Table 1 presents information for all of the OEM companies reporting in 2001, and for the companies represented by the National Electrical Manufacturers Association (NEMA) only for 2001 and 2004.  NEMA-member lamp manufacturers include General Electric, Osram Sylvania, Philips, Eye Lighting, Halco, Light Sources, Panasonic, Ruud Lighting, SLI, Ushio, Venture Lighting, and Westinghouse.   For 2004 only the data reported by NEMA are provided because the data for all manufacturers are not yet available for that year.

TABLE 1: TOTAL AMOUNT OF MERCURY SOLD BY LAMP TYPE, 2001 and 2004
Lamp Type	All Companies 2001 Pounds Mercury (percent of total)	NEMA Companies Only, 2001 Pounds Mercury (percent of total)	NEMA Companies Only, 2004 Pounds Mercury  (percent of total)
Fluorescent	14,536 (77%)	14,211 (79%)	12,182 (76%)
CFL	869 (5%)	599 (3%)	650 (4%)
All HID Lamps*	2,951 (16%)	2,721 (15%)	3,079 (19%)
Metal Halide	NA	NA	2,385 (15%)
Ceramic Metal Halide	NA	NA	31 (0.2%)
High Pressure Sodium	NA	NA	451 (2.8%)
Mercury Vapor	173 (1%)	NA	212 (1.3%)
Misc. Specialty Lamps**	508 (3%)	508 (3%)	NA
Mercury Short Arc	10.4 (<1%)	NA	13 (.08%)
Mercury Capillary	13 (<1%)	NA	0.2 (.01%)
Total Mercury	18,737	18,039	15,924
* 2001 data do not break out HID lamps by specific types; however, a few manufacturers provided this information. ** This category includes some HID lamps, but it was not possible to separate them out from the other lamps in the category.

In 2001, all the companies reporting to the IMERC-member states sold approximately 9.4 tons of mercury in mercury lamps.  Ninety-six percent of this mercury was sold in lamps manufactured by NEMA-member companies.  The total amount of mercury sold is likely an underestimate because the database contains few filings from lamps produced in other countries, such as China and India.  It is also likely that many speciality lamp manufacturers have not yet reported to IMERC.  For example, few neon light manufacturers have reported.

The Neon Products Gruppe estimates that an additional 2 to 6 tons of mercury is sold in neon lights in the United States each year.  They base this figure on estimated annual sales volume of 8 to 10 million mercury-containing neon lamps (Neon Products Gruppe, 2004).

In 2004, the total amount of mercury sold by NEMA-member companies decreased about 10 percent, from 9 tons to 8 tons.  This drop in the total amount of mercury sold in lamps may be attributed to manufacturers’ efforts to develop lamps with lower amounts of mercury.

The lower amount of mercury sold in 2004 could also possibly reflect the growing number of foreign manufacturers selling flourescent lamps in the United States. 

Table 1 also shows the total amount of mercury sold by lamp type.  Fluorescents make up the majority, representing more than 75 percent of the total amount of mercury sold in both 2001 and 2004.  HID lamps constitute the second largest amount of mercury sold in lamps in both years.  The data for 2004 show that the majority of the mercury sold in HID lamps was in the metal halide category.

CFLs contain only about 4 percent of the mercury sold in lamps, as reported to the IMERC-member states.  Due to the potential for underreporting, it is likely that CFLs contain more than 4 percent of the mercury going into lighting; however, it is doubtful they represent substantially more because each lamp contains a relatively small amount of mercury.  Two-thirds of the CFLs sold in the U.S. in 2004, as reported to the IMERC-member states, contained 5 milligrams of mercury or less (see Table 2).

Amount of Mercury Used in Individual Lamps

Table 2 summarizes the amount of mercury sold in individual lamps by lamp type for calendar year 2004.  This data was reported to the IMERC-member states by the National Electrical Manufacturers Association (NEMA) member companies.  For a more detailed breakdown on the amount of mercury sold in individual lamp types, including wattages, see the Appendix.

Table 2:  Summary of Data on Mercury Use in Individual Lamps Sold by NEMA-Member Companies in 2004
Lamp Type	Amount of Mercury in Lamp (mg)	Percent of Lamps with Specified Mercury Amount
Fluorescent	0 – 5 > 5 – 10 >10 – 50 > 50 -100	12 48.5 27 12.5
CFL	0-5 > 5  to 10 >10-50	66 30 4
Metal Halide	>10-50 >50-100 >100- 1,000	24 40 35
Ceramic Metal Halide	0-5 >5-10 > 10 to 50	17.6 46.8 35.6
High Pressure Sodium	>10-50	97
Mercury Vapor	>10-50 >50-100 >100- 1,000	58 29 12
Mercury Short Arc	>100-1,000 >1,000	65 23
Mercury Capillary	>100-1,000	100

Sixty percent of all the fluorescent lamps sold in 2004 contained 10 milligrams of mercury or less.  The remaining 40 percent contained from more than 10 up to 100 mg of mercury.  

While data are not available on the amount of mercury used in the different types of fluorescent lamps for 2004, in 2001 NEMA reported amounts used in a few types of fluorescent lamps.  Lamps used in sun tanning equipment, for example, were reported to contain an average 17 mg per lamp, with a high of 20 mg and a low of 5.5 mg. Germicidal lamps were reported to contain an average of 7.6 mg mercury, with a high of 70 and a low of 5.5 mg.  Four foot linear fluorescent lamps reportedly contained an average of 13.3 mg, with a high of 70 mg and a low of 2.5 mg; while 4-foot TCLP-passing[2] lamps contained an average 5.3 mg with a high of 20 and a low of 1.4 mg.

Compact fluorescents had the least amount of mercury sold per lamp in 2004.  Two-thirds contained 5 mg or less, while 96 percent contained 10 mg or less. 

HID lamps as a class contained relatively larger amounts of mercury in individual lamps sold in 2004.  Of all the HID lamps, the MH lamps contained the largest amounts of mercury.  Nearly three-quarters of the MH lamps sold in 2004 by NEMA-member companies contained from more than 50 up to 1,000 mg of mercury.

Mercury short arc and mercury capillary lamps also contained relatively large amounts of mercury.  Two-third of mercury short-arc lamps contained 100 to 1,000 mg of mercury with an additional 23 percent containing more than 1,000 mg. Mercury capillary lamps all contained greater than 100 mg of mercury.

References:

Neon Products Gruppe,  September 10, 2004 letter to IMERC.

Fluorescent Technology, Sylvania
http://www.sylvania.com/LearnLighting/LightAndColor/FluorescentTechnology

HID Technology, Sylvania
http://www.sylvania.com/LearnLighting/LightAndColor/HIDTechnology/

Pacific Energy Center Fact sheet: Metal Halide Lamps
http://www.pge.com/pec

Pacific Energy Center Fact sheet: Fluorescent Lamps
http://www.pge.com/pec

Pacific Energy Center Fact sheet: High Pressure Sodium Lamps
http://www.pge.com/pec

Pacific Energy Center Fact sheet: Compact Fluorescent Lamps
http://www.pge.com/pec

Ceramic Metal Halide, lighting design lab news, winter/spring 2003

References that estimate amount of mercury released from individual fluorescent lamps when broken:

Aucott M, McLinden M, Winka M, 2003, Release of Mercury from Broken Fluorescent Bulbs, Journal of the Air & Waste Management Association, 53:143-151.

Lindberg SE, Roy K, Owens J, “PaMSWaD, 1999b, (Pathways of mercury in solid waste disposal), ORNL sampling operations summary and preliminary data report for PaMSWaD-I,” Brevard County Landfill, February 6.

Appendix

TABLE 3: TOTAL MERCURY SOLD IN 2004 IN LAMPS AS REPORTED BY NEMA-MEMBER COMPANIES
Lamp Type	Total Amt Mercury Sold	Wattage	Percent of Mercury Sold Within Lamp Type	Percent of  Mercury Sold  for All Lamp Types
Fluorescent
0 – 5 mg	671,741	4-80	12.13
> 5 – 10 mg	2,684,343	4-212	48.48
>10 – 50 mg	1,488,128	4-1500	26.88
> 50 -100 mg	692,991	6-800	12.52
Total	5,537,202			76.5
Compact Fluorescent
0 – 5 mg	196,134	3-80	66.41
> 5 – 10 mg	87,527	7-70	29.64
>10 – 50 mg	11,677	15-150	3.95
Total	295,338			4.1
Metal Halide
0 – 5 mg	2,595	32-200	0.24
> 5 – 10 mg	5,679	48-200	0.52
>10 – 50 mg	266,005	15-1200	24.54
> 50 -100 mg	430,040	50-5,000	39.67
>100-1,000	379,096	400-8,000	34.97
> 1,000	721	12,000-18,000	0.07
Total	1,084,136			15
Ceramic metal halide
0 – 5 mg	2441	20-400	17.60
> 5 – 10 mg	6,490	50-250	46.79
>10 – 50 mg	4,939	150-400	35.61
Total	13,870			0.2
High pressure sodium
0 – 5 mg	1,866	35-400	0.91
> 5 – 10 mg	1,297	35-400	0.63
>10 – 50 mg	199,826	35-1,000	97.42	2.8
> 50 -100 mg	2,121	250-1,000	1.03
Total	205,110
Mercury vapor				1.3
> 5 – 10 mg	345	50-175	0.36
>10 – 50 mg	55,764	40-400	57.74
> 50 -100 mg	28,361	100-1,000	29.36
>100-1,000	12,116	250-1,000	12.54
Total	96,586
Mercury Short-arc and Mercury Xenon Short-arc
>10-50	476	50-350	7.87
>50-100	253	50-2,000	4.18
>100-1000	3953	200-3,500	65.33
.>1000	1369	1,000-8,000	22.62
Total	6051			0.08
Mercury Capillary
>100-1,000	82	3,000-6,500	100
Total	82			0.01

Appendix:
 Original Equipment Manufacturers
Reporting Sale of Mercury in Lamps to IMERC

Advanced Radiation Corp	Osram Sylvania
AutoCell Electronics	Panasonic
Axcelis Tech	Perfecto Manufacturing
BHK Inc	PerkinElmer
CEW lighting	Philips
EGL Company	Ruud Lighting
Elevam Corp	Sankyo Denki Co
Eye Lighting	Satco Products
Fanlight Corp	SLI
Feit Electric	Superior Quartz Products
First Light Technologies	Technical Consumer products
Fujian Joinluck Electronics	Ultra-Lum Inc
Gavenco LLC	Ushio
General Electric	UVP inc
Grakon International	Venture Lighting
Halco	Verilux
Harison Toshiba Lighting	Volarc Technologies
Interlectric Lighting Supplies Inc	Wellypower Optronics
Light Sources	Western Quartz products
Marineland	Westinghouse
Micro Lamps

Companies in bold are NEMA-member companies.