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The Strategy Guideline: High Performance Residential Lighting has been developed to provide a tool for the understanding and application of high performance lighting in the home. The high performance lighting strategies featured in this guide are drawn from recent advances in commercial lighting for application to typical spaces found in residential buildings. This guide offers strategies to greatly reduce lighting energy use through the application of high quality fluorescent and light emitting diode (LED) technologies. It is important to note that these strategies not only save energy in the home but also serve to satisfy the homeowner's expectations for high quality lighting.

The use of a footcandle meter to measure light intensity is not accurate when comparing different light sources. Light intensity measurements were determined for ten different light sources used commonly by the poultry industry. Measurements were made using footcandles and photons for each light source. A correction factor to equate light intensities as photons per footcandle was produced to allow replacement of one light source with another and still maintain the same light intensity in photons.

NFPA 101, section 5-9 mandates that, where required by building classification, all designated emergency egress routes be provided with adequate emergency lighting in the event of a normal lighting outage. Emergency lighting is to be arranged so that egress routes are illuminated to an average of 1.0 footcandle with a minimum at any point of 0.1 footcandle, as measured at floor level. These levels are permitted to drop to 60% of their original value over the required 90 minute emergency lighting duration after a power outage. The Plutonium Finishing Plant (PFP) has two designations for battery powered egress lights ''Emergency Lights'' are those battery powered lights required by NFPA 101 to provide lighting along officially designated egress routes in those buildings meeting the correct occupancy requirements. Emergency Lights are maintained on a monthly basis by procedure ZSR-12N-001. ''Backup Lights'' are battery powered lights not required by NFPA, but installed in areas where additional light may be needed. The Backup Light locations were identified by PFP Safety and Engineering based on several factors. (1) General occupancy and type of work in the area. Areas occupied briefly during a shiftly surveillance do not require backup lighting while a room occupied fairly frequentlymore » or for significant lengths of time will need one or two Backup lights to provide general illumination of the egress points. (2) Complexity of the egress routes. Office spaces with a standard hallway/room configuration will not require Backup Lights while a large room with several subdivisions or irregularly placed rooms, doors, and equipment will require Backup Lights to make egress safer. (3) Reasonable balance between the safety benefits of additional lighting and the man-hours/exposure required for periodic light maintenance. In some plant areas such as building 236-Z, the additional maintenance time and risk of contamination do not warrant having Backup Lights installed in all rooms. Sufficient light for egress is provided by existing lights located in the hallways.« less

Using an array of footcandle values for points across and along a street is common practice in analyzing roadway lighting. To make the job easier, this array is enhanced by superimposing a series of iso-contour lines for several levels of illumination. Sometimes the grid of values is simply replaced altogether by an iso-contour plot. Presented here is an enhancement that will allow even a layman to readily comprehend the distribution of illumination over a roadway surface.

Measurements from standard illuminants in the ultraviolet and calculations have revealed that some proposed public health standards for ultraviolet irradiance are exceeded at relatively low footcandle levels. This study compares the actual ultraviolet irradiance at the work task with calculated values. It will also provide a beginning to the development of design data for the prediction of ultraviolet irradiance in lighting Installations.

This paper presents a simple coefficient method of calculating average vertical illumination. Two new coefficients are introduced, the vertical coefficient of utilization (VCU) and the directed coefficient of utilization (DCU). The vertical coefficient of utilization predicts the average of all possible vertical footcandle readings over a three-dimensional grid within a room. The directed coefficient of utilization, based on balanced horizontal and vertical illumination, is a relative measure of three-dimensional lighting effectiveness; and it can be used to recommend wide or narrow beam luminaires according to room parameters.

Recent domestic and international developments with smaller diameter fluorescent lamps have prompted a review of lamp and system performance as a function of tube diameter. Limiting constraints on system performance when lamps of various diameter are used with the standard rapid start ballast are discussed. Performance comparisons are also made when these various diameter lamps are mated with ballasts optimized specifically for both 60 HZ and high frequency operation. The role of lumen maintenance in affecting the mean footcandle level throughout the lamp life is a key issue in these discussions.

With the the growing popularity of solaria and increasing public acceptance of sources generating erythemal ultraviolet, there is a definite need in the field for a rugged, compact direct-reading meter that will measure the E-Vitons per square foot in the same way that a footcandle meter measures lumens/square foot. E-Vitons are the unit to express the health and erythema value of radiations above 2,800 Angstrom units. The design of such a meter is discussed.

The ever-increasing trend towards higher footcandle levels has created problems of heat removal. Air handling luminaires are now the most popular way of removing this excess heat. Water-cooled luminaires provide a more efficient way of removing heat from the occupied space and offer advantages of versatility as compared with conventional, or air handling type, fixtures. Design criteria, problems of potential corrosion, and installation and maintenance procedure are discussed. Curves are provided to indicate performance of these fixtures and to show typical heating and cooling system comparisons between water-cooled and other types of systems. Water flow rates of 1/2 gallon per minute of 77°F water can effectively remove 70 percent of the heat generated in a water-cooled fixture.

1. The cyprid larvae of Balanus improvisus were found to settle in a diurnal rhythm with maximum numbers attaching during daylight hours.2. No consistent pattern of vertical distribution of the cyprids was found.3. The normal diurnal cycle in rate of attachment of barnacle cyprids was nullified by the use of artificial illumination over the collecting surfaces at night.4. The magnitude of the cyprid collection on the artificially illuminated surfaces was equal to the collection on the sun-illuminated surfaces in daylight.5. The intensity of artificial light necessary to produce large cyprid attachments at night was of an order as low as 1 footcandle at the water surface.6. No correlation was found between the quantity of artificial light at night and the numbers of cyprids attached.7. The highest rate of cyprid attachment relative to the phase of the tide was found to occur when the waters of upper Biscayne Bay were sampled at the collecting station. This body of water reached the sampling station at low ...

We are increasingly being warned of the possible effects of so called "polluted" light, that is light that differs in spectral content from that of sunlight. We should be concerned, we are told, because all animals and plants have evolved under this natural daylight and therefore any difference between that illuminant and the artificial illuminants that are on the market today, is suspect. The usual presentation of the differences between the sunlight and the artificial illuminants are as shown in Figure 1. Here we are shown the spectral power distribution of sunlight and Cool White fluorescent light. The spectral power distributions of each have been normalized to some convenient wavelength so that each can be seen and easily compared on the same figure. But this presentation is misleading for one does not experience artificial illuminants at the same intensity as one experiences sunlight. Sunlight intensities are ordinarily found to be in the 8000 to 10,000 footcandle range whereas artificial illuminants are rarely experienced at intensity levels greater than 100 footcandles. Therefore a representative difference between the two types of illumination conditions is more accurately represented as in Figure 2. Thus if evolutionary adaptations require that humans and other animals be exposed to sunlight to ensure wellbeing, it is clear that one must be exposed to sunlight intensities. It is not feasible to expect that artificially illuminated environments will be lit to the same intensity as sunlight© (1980) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.

As already outlined, electric discharge lamps are extremely common, with some two billion fluorescent lamps and 0.2 billion high intensity discharge (HID) lamps in service around the world (not counting USSR and mainland China), not to mention perhaps 5–10 million low-pressure sodium lamps. Taking 2500 lumens as the average light output per fluorescent lamp, and 15,000 lumens as the average light output per HID lamp, if all were lighted at once, about 8×1012 lumens would be generated. In turn, if this were distributed over the entire land area of the globe (7.2×1017 sq cm), the net illumination would be 10‒5 lumens/cm2, 0.1 lumens/m2 = 0.1 lux (ca 0.01 footcandle). This is about the illumination level of bright moonlight from a full moon.

Multimirror Quartzline Lamps are extremely versatile and effective for nonconventional imaging requirements such as high-speed photo and video instrumentation and high-magnification imaging. The lamps' versatility though, is not limited to conventional environments. Many research experiments and projects require a high pressure environment. Continuous photographic data acquisition in a high-pressure vessel requires wall penetrations and creates design problems as well as potential failure sites. Underwater photography adds the extra consideration of a liquid. This report expands upon the basic research presented in, Performance of Multimirror Quartzline Lamps in High-Pressure Environments, (NASA-TM-83793, Ernie Walker and Howard Slater, 1984). The report provides information to professional industrial, scientific, and technical photographers as well as research personnel on the survivability of lighting a multimirror quartzline lamp in a nonconventional high-pressure underwater environment. Test results of lighted ELH 300 W multimirror quartzline lamps under high-pressure conditions are documented and general information on the lamps' intensity (footcandle output), cone of light coverage, approximate color temperature is provided. Continuous lighting considerations in liquids are also discussed.

A laboratory experiment was conducted on a terrain model to assess the effect of a hovering flare on target acquisition performance. One group of subjects was asked to search for targets of opportunity by the light of two hovering flares. Another group searched with two normally descending flares. The hovering flare group found 59% of the targets as compared to 52% by the descending flare group. Although this difference is statistically significant, its operational significance is open to question. The data are shown to be directly related to the area on the ground illuminated by 0.2 footcandle.

Seeing is a complex human activity involving more than the visual sense and its ability to convert the stimulus, radiant energy, into sensations of brightness and color. Seeing is accomplished by the human being operating as a human seeing-machine. Therefore, efficient, certain, comfortable, and easy seeing involves psychophysiological factors and effects of seeing as well as the psychophysical characteristics of the visual task and its environment. There is some confusion and some difference of opinion in regard to levels of illumination that are now being recommended. This is not surprising inasmuch as recommended footcandle levels are very generally compromises involving many aspects of economics, practicability, and conservation. Adequate specifications of light, lighting, brightness, and color do not arise from a single study or even a limited group of studies. Pertinent data are yielded by researches along various major avenues involving achievement, conservation of human resources, subnormal as well as normal vision, supra-threshold as well as threshold visibility, and proper considerations of footcandle level as a means to the ends which are brightness level and visibility level. The author presents data and analyses which reply specifically to certain criticisms and which, he believes, support the conclusion that footcandle levels recommended by the Illuminating Engineering Society, as well as by himself and colleagues, are conservative in relation to the indicated ideal levels for various tasks of prolonged critical seeing.