CIE Division 6 - New Terms:

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1 CIE Division 6 - New Tms: additivity law of von Krefeld effective doses can be added to a total effective dose, even if the dose response curves for diffent wavebands are diffent (This means at the same time that no conductive, i.e. catalytic, or hinding, i.e. antagonistic effects occur.) (ref: CIE ) albedo (bihemisphical reflectance); spectral albedo (spectral bihemisphical reflectance) ratio of incoming radiation reflected by a surface to the radiation incident upon it This quantity is unitless and is typically expressed as a numb between 0 (pfect absorb) and 1n0 (pfect reflector). Normally the albedo varies as a function of wavelength. This tm is primarily used in meteorology. unit: unitless (ratio) (source: CIE 151:2003) angular subtense (α) visual angle subtended by the apparent source at the eye of an obsv or at the point of measurement Subtended angles are denoted by the full included angle, not the half angle. unit: radian Note. - The angular subtense α will genally be modified by incorporation of lenses and mirrors as projector optics, i.e. the angular subtense of the apparent source will diff from the angular subtense of the physical source. apture, apture stop opening that defines the area ov which avage optical emission (Schulmeist: use radiation levels instead of emission ) is measured For spectral irradiance measurements this opening is usually the entrance of a small sphe placed in front of the radiomet/spectroradiomet entrance slit. blue light hazard (BLH) potential for a photochemically induced retinal injury resulting from optical radiation exposure at wavelengths primarily between 400 nm and 500 nm This damage mechanism dominates ov the thmal damage mechanism for exposure durations exceeding 10 seconds. The action spectrum extends into the UV-A for psons without a normal UV-A absorbing lens. blue light hazard spectral weighting function b(λ) relative spectral sensitivity of the eyes to blue light hazards; based upon the relative spectral effectiveness of optical radiation to induce retinal photochemical injury (photic maculopathy) Note. - Specified in ICNIRP-recommendations for λ = nm. unit: unitless (relative value) 1

2 blue light hazard irradiance (E b ) effective photobiological irradiance with the spectral radiance E λ spectrally weighted with the blue light hazard weighting function b(λ) in the wavelength range λ 1 to λ 2 This quantity is typically of intest for small sources subtending less than 0,011 radian. unit: W m - ² [effective] blue light hazard radiance (L b ) effective photobiological radiance with the spectral radiance L λ spectrally weighted with the blue light hazard weighting function b(λ) in the wavelength range λ 1 to λ 2 unit: W m - ² sr -1 [effective] blue light hazard (time) integrated radiance; blue light hazard radiance dose (L b,t ) time-integral of the blue light radiance L b as integrated with respect to the duration of exposure t exp unit: J m - ² sr -1 [effective] Note. - See radiance dose; (time) integrated radiance blue light hazard radiant exposure (H b ) effective photobiological radiant exposure with the radiant exposure H λ spectrally weighted with the blue light hazard weighting function b(λ) in the wavelength range λ 1 to λ. unit: J m - ² [effective] Bunsen-Roscoe Law (Reciprocity) photochemical reaction will commonly exhibit reciprocity between irradiance (exposure dose rate) ov some range of exposure duration This is tmed the "Bunsen-Roscoe Law". That is, a given radiant exposure in J/m 2 is required to elicit a given response regardless of exposure duration ov a wide range of exposure durations. Repair mechanisms, recombination ov long piods and photon saturation for extremely short piods will lead to reciprocity failure. The product of irradiance E in W/m 2 and exposure duration t exp is the radiant exposure H in J/m 2, i.e., H = E t exp Note. - While both E and H may be defined ov the entire optical spectrum, it is necessary only to weight these quantities ov the extent of the action spectrum for photochemical effects. (ref: CIE ) circadian rhythm biological rhythm with a piod of approximately 24 hours continuous wave (CW) lamp lamp that is opated with a continuous output In photobiological safety, opated for a time great than 0,25 s, i.e., a non-pulsed lamp. Note. - In CIE Standard S009, Genal lighting svice (GLS) lamps are defined to be continuous wave lamps. dose response curve relative biological response with increasing radiant exposure (photobiological dose) ythema action spectrum (s (λ)) spectral dependence of the ability of UV radiation to produce just pceptible ythema in human skin 2

3 (ref: CIE S ) ythemal effective irradiance (E ) quantity defined by the equation: E = Eλ s dλ whe E λ is the spectral irradiance in W m -2 nm -1 and s (λ) is the ythema action spectrum normalized to its maximum (ref: CIE S ) ythemal effective radiant exposure; ythemal dose (H ) time integral of ythemally effective irradiance defined by the equation H = E t) s dλ dt λ ( whe E λ (t) is the spectral irradiance in W m -2 nm -1 and s (λ) is the ythema action spectrum (ref: CIE S ) See minimal ythema dose and standard ythema dose exposure distance point of human exposure from a lamp or lamp system For lamp safety evaluations, this is the nearest distance consistent with the application of the lamp or lamp system. For lamps radiating in all directions the distance is measured from the centre of the filament or arc source. For reflector-type lamps the distance is measured from the outside edge of the lens or the plane defining the end of the reflector in a lens free reflector. unit: m exposure duration; duration of exposure (t exp ) time diffence between the end time t e and the start time t s of a radiation exposure (as used in photochemistry and photobiology) unit: s exposure limit (EL) level of exposure to the eye or skin that is not expected to result in advse biological effects Note. - Optical radiation ELs are normally recommended by the Intnational Commission on Non-Ionizing Radiation Protection (ICNIRP). field of view solid angle as "seen" by the detector (acceptance angle), such as the radiomet/ spectroradiomet, out of which the detector receives radiation unit: sr Notes The field of view should not be confused with the angular subtense of the apparent source α A plane angle is sometimes used to describe a circular symmetric solid angle field of view. 3

4 genal lighting svice (GLS) lamps lamps intended for lighting spaces that are typically occupied or viewed by people Examples would be lamps for lighting offices, schools, homes, factories, roadways, or automobiles. It does not include lamps for such specialized uses as film projection, reprographic processes, "sun-tanning", industrial processes, medical treatment and searchlight applications. A tm used in detmining the photobiological safety of lamps (see: CIE S009:2002). global UV index quantity developed for the public domain, for weath forecasting and climatology which quantifies the ythemal potential (or sunburning pow) of the ambient solar UV radiation (or I UV = k 400nm E λ 250nm s dλ sunlight), but could also be applied to oth sources The Intnational Global UV Index (I UV ) is a unitless quantity defined by the formula: whe E λ is the solar spectral irradiance expressed in W m -2 nm -1 at wavelength λ s (λ) is the ythema action spectrum developed by CIE k is a constant equal to 40 m 2 /W. (ref: CIE S 013:2003) infrared "heat" cataract hazard clouding (opacification) of the lens resulting from life-long exposure to excessive nearinfrared radiant engy producing an elevated tempature of the lens (ref: CIE 134/3-1999) large source size of the source image on the retina which is so large that radial heat flow from the centre of the image to the surrounding biological tissue is negligibly small compared to heat flow in the axial direction las (acronym for light amplification by stimulated emission of radiation") source emitting cohent optical radiation produced by stimulated emission light thapy exposure of the human eye to visible radiation for the treatment of affective disords (e.g. Seasonal Affective Disord or wint depression) or disords due to circadian disruption (e.g. Advanced Phase Sleep Disord, circadian desynchronization related to shift work or jet travel) melatonin hormone hormone secreted from the pineal gland Levels of melatonin in the pineal gland, blood, saliva, and urine fluctuate in a circadian rhythm, high at night and low in the daytime, by reacting to natural daylight (or artificial) photopiods. 4

5 ocular hazard distance distance from a source within which the radiance or irradiance for a given exposure duration exceeds the applicable exposure limit unit: m photic maculopathy; photoretinitis retinal injury produced by staring at an extremely bright light source photocarcinogenesis carcinogenesis resulting from exposure to photons (of ultraviolet radiation) photocataractogenesis clouding (opacification) of the lens resulting in most cases from life-long chronic exposure to excessive ultraviolet radiant engy incident upon the lens Cataract may also be produced by acute ovexposure to an excim las. (ref: CIE 134/3-1999) photochemical carcinogenesis carcinogenesis resulting from a reaction with a photoactivated drug or chemical photococarcinogenicity direct (photochemical carcinogenesis) or indirect enhancement of UV-associated skin carcinogenesis (e.g., sunlight-associated carcinogenesis) by a drug or chemical photocuring effect of a liquid-state polym changing into the solid state, becoming insoluble to solvent or increasingly resistant to corrosive chemicals, by optical irradiation photodynamic thapy See photothapy photoimmunology study of the effects of optical radiation upon the immune system Effects may be localized or systemic and mediated through the skin. photokatoconjunctivitis inflammatory response of the cornea and conjunctiva following exposure to ultraviolet (UV) radiation Wavelengths short than 320 nm are most effective in causing this condition. The peak of the action spectrum is approximately at 270 nm. Common synonyms are snowblindness, arc eye, and weld s flash. Note. - Diffent action spectra have been published for photokatitis and photoconjuctivitis (CIE 106/2 and CIE 106/3 1993); howev, the latest studies support the use of a single action spectrum for both ocular effects (CIE 106/1 1993). photomorphogenesis propty of plants which enables them to utilize radiant engy to control the growth and development of their cells, tissues and organs 5

6 photomutagenesis production of mutations induced by exposure to optical radiation photopiodism response of organisms to length of the night and day piods, and change in these piods with the natural progression of the seasons or manipulation of day length with artificial light photosynthesis convsion of light engy to engy in chemical bonds Photosynthesis in plants is well known and involves assimilation of carbon dioxide into simple sugars. The engy from sunlight or artificial light (principally in the nm waveband), is convted into chemical bond engy in the sugars. Photosynthesis in the skin occurs when 7-dehydrocholestol in the skin absorbs UVB solar radiation and is convted to previtamin D 3. photosynthetically active radiation (PAR) total photon exposure in the nm waveband reported as mol m -2 p unit time as: mol m -2 s -1 (sec), or mol m -2 d -1 (day) phototaxis propty of mobile organisms to move in response to light For example, positive phototaxis involves movement (such as in swimming) toward a light source and negative phototaxis away from a light source. phototropism change in direction of growth of plant parts (cells, tissues, and/or organs) in response to a directional source of radiation For example, plant stems will typically bend toward a light source and leaves will change orientation such that their upp surfaces tend to be ppendicular to a light source. pulsed lamp lamp that delivs its engy in the form of a single pulse or a train of pulses whe each pulse is assumed to have a duration of less than 0,25 s A lamp with a continuous train of pulses or modulated radiant engy whe the peak radiated pow is at least ten times the avage radiated pow. Notes The duration of a lamp pulse is the time intval between the half-peak-pow points on the leading and the trailing edges of the pulse In CIE Standard S-009/E, Genal lighting svice lamps are defined to be Continuous wave lamps. Examples of pulsed lamps include photoflash lamps, flash lamps in photocopy machines, pulse-modulated LEDs, and strobe lights. radiance dose; (time) integrated radiance (in a given direction, at a given point of a real or imaginary surface) (L t ) quantity defined by the formula L dq = e da cosθ dω whe dq e is the radiant engy transmitted by an elementary beam passing through the given point and propagating in the solid angle dω containing the given direction; da is the area of a 6

7 section of that beam containing the given point; θ is the angle between the normal to that section and the direction of the beam unit: J m -2 sr -1 Notes 1 to 4. In the four following notes the symbols for the quantities are without subscripts because the formulas are also valid for the tms and For an area da of a surface receiving the beam, since the radiant exposure or luminous exposure dh produced by the beam on da is dh = dq/da, then an equivalent formula is L dh =, dω cosθ a form useful when the source has no surface (e.g. the sky, the plasma of a discharge). 2. Making use of the geometric extent dg of the elementary beam, since dg = da cos θ dω, then an equivalent formula is L = dq/dg. 3. Since the optical extent G n 2 (see Note to ) is invariant, then the quantity L n -2 is also invariant along the path of the beam if the losses by absorption, reflection and diffusion are taken as zo. That quantity is called the basic integrated radiance or basic integrated luminance or basic integrated photon radiance. 4. The relation between dq and L given in the formulae above is sometimes called a corollary to the basic law of radiometry and photometry: da cosθ da' cosθ ' dq = L = L da cosθ dω = L da' cosθ ' dω' 2 I with the notation given he and at reciprocity See Bunsen-Roscoe Law (Reciprocity) retinal burn retinal lesion produced by intense visible or IR-A exposure Genally used to describe a thmal retinal lesion (see retinal thmal injury ); howev, sometimes applied to a photochemical retinal lesion. More specific tms are also used for a photochemical burn, i.e., a photomaculopathy or blue light photoretinitis (from blue light induced injuries) or for a retinal thmal injury, a chorioretinal thmal injury. retinal hazard spectral region spectral region from 380 nm to 1400 nm (visible plus IR-A) within which the normal ocular media transmit optical radiation to the retina retinal thmal hazard spectral weighting function r(λ) normalized spectral sensitivity of the eyes due to retinal thmal hazards Note. - Specified in ICNIRP-recommendations for λ = nm. retinal thmal injury, "retinal burn" retinal injury caused by brief, intense radiant exposure of the retina from wavelengths in the retinal hazard region (approximately 380 nm to 1400 nm; visible plus IR-A) within which the normal ocular media transmit optical radiation to the retina The maximum assessment time in CIE Standard S009/E:2002 is taken as 10 s. Note. - In some cases a blue light photoretinitis is also tmed a "retinal burn". (ref: CIE 134/3-1999) 7

8 retinal thmal radiance (L r ) effective photobiological radiance with the spectral radiance L λ spectrally weighted with the retinal thmal hazard weighting function r(λ) in the wavelength range λ 1 to λ 2-1 unit: W m -2 sr [effective] skin hazard distance distance from a source at which the irradiance exceeds the applicable exposure limit for the skin for the duration of exposure When the duration of exposure is not known, CIE S009 applies a duration of 8 hours. unit: m spectral irradiance (E λ ) quotient of the radiant pow dφ(λ) in a wavelength intval dλ, incident on an element of a surface, by the area da of that element and by the wavelength intval dλ dφ Eλ = d A dλ unit: W m -2 nm -1 spectral radiance (for a wavelength intval dλ, in a given direction at a given point) (L λ ) ratio of the radiant pow dφ(λ) passing through that point and propagating within the solid angle dω in the given direction, to the product of the wavelength intval dλ and the area of a section of that beam on a plane ppendicular to this direction (cos θ da) containing the given point and to the solid angle dω dφ Lλ = d A cosθ dω dλ unit: W m -2 nm -1 sr -1 sun protection factor (SPF) measurement of the protective quality of a sunscreen against solar ultraviolet radiation, detmined by in vivo testing normally using an optical radiation source whose spectral output simulates the UV component of summ sunlight The sun protection factor (SPF) is detmined by comparing the dose of solar simulated UVR required to produce just-pceptible ythema approximately 24 hours aft exposure in UVRirradiated human voluntes, with and without a standard amount of the sunscreen being present (MED f and MED i, respectively) and is calculated as follows: MED f SPF = MEDi (Diffey) standard ythema dose (SED) standardized unit of measure of ythemogenic UV radiation 1 SED is equivalent to an ythemal effective radiant exposure of 100 J m -2 (ref: CIE S ) 8

9 sunlamp artificial source of optical radiation designed to promote tanning of the human skin; genally designed to emit substantial ultraviolet radiation ultraviolet hazard irradiance (E s ) effective photobiological irradiance detmined by spectrally weighting the spectral irradiance E λ with the ultraviolet protection weighting function s(λ) in the wavelength range λ 1 to λ 2 unit: W m -2 ultraviolet hazard radiant exposure (H s ) biologically effective radiant exposure detmined by spectrally weighting the radiant exposure H λ with the ultraviolet protection weighting function s(λ) in the wavelength range λ 1 to λ 2 unit: J m -2 Note. - New quantity designation proposed. ultraviolet hazard spectral weighting function s(λ) combines the normalized spectral sensitivities of the eyes and skin to UV-radiation for radiation protection purposes Note. - Specified in ICNIRP-recommendations for λ = nm. ultraviolet photocataractogenesis See photocataractogenesis. ultraviolet protection factor (UPF) measurement of the protective quality of a fabric sample against solar ultraviolet radiation, detmined by in vitro testing The ratio of the ythemally weighted solar UVR irradiance measured by a detector with the fabric sample-und-test in place is compared to the ythemally weighted solar UVR irradiance measured with no fabric present. For in vitro testing, the light source is typically a solar simulator. This is expressed in the following equation: Effective Dose Without Fabric UPF = = 400 Effective Dose Through Fabric E λ E λ s s λ τ λ whe s (λ) is the relevant biological action spectrum; i.e., the relative ythemal spectral effectiveness (unitless). E λ is the solar UVR spectral irradiance in W m -2 nm -1 τ(λ) is the measured spectral transmission of the item λ is the bandwidth in nm λ is the wavelength in nm Note. The UV hazard spectral weighting function s(λ) has been substituted for s (λ) in special instances. If so used, the UPF must be noted as UPF[s(λ)-weighted]. visual angle angle subtended by an object or detail at the point of obsvation The SI unit for the angle is the radian although it may also be measured in milliradians, degrees, or minutes of arc. 9

10 See also angular subtense. vitamin D synthesis process that 7-dehydrocholestol, precursor of vitamin D, produces previtamin D by absorbing nm ultraviolet radiation and moreov changes it to vitamin D through a thmal isomization process Note. - Vitamin D is a genic tm of vitamin D 2 - vitamin D 3. (Holick) 10