CA2117345A1 - Video fluorescence monitor for determination of pcb or pcb mineral oil spill outline - Google Patents

Abstract

Disclosed is a real-time fluorescence imaging system for detecting the presence and boundaries of spills of insulating liquids for transformers and capacitors and providing a two dimensional image of the spill having excitement means (12) positionable near a spill for exciting fluorescent emissions of the insulating liquids, image intensification means (31) for intensifying the fluorescent emissions, first detection means (13) positionable to detect intensified fluorescent emissions from the insulating liquids and generating a detection signal, and display means (14) for receiving the detection signal and generating a real-time video image of the presence and boundaries of the spill. The present invention also includes pulse means (32) for causing the excitement means (12) to periodically excite fluorescent emissions from the insulating liquids and control means (33) for controlling the intensification means (31) to intensify only during periods of fluorescent excitation.

Description

CA2117345 ;~
~' 93/13404 PCl`/US92/11344 ~7IDEO FLUORESCENCE MONITOR FOR
DEl'ERMINATION OF PCB OR PCB MINERAL OIL SPILL OUTLINE
Field of the Invention This invention relates to a video fluorescent monitor. More specifically, it relates tO a~ apparatus and method for real-time on-site video imaging for the detection of ~he presenc~ and boundaries of a spill of material of fluorescent type OIl surfaces. PCB, PC~
contaminated mineral oil-based fluorescing mixtures, and mLneral oil-based insulating li~uids are specifically included.
Background of the Invention - 10 Spills of iusulating liquids for transformers and capacitors on many surfaces of~en cannot be seeII readily by the eye. The presence and boundaIies of a spill have typically been determinet by applying costly and time~cor~g sta~istical samplingprocetures.
Furthennore, more sampliIIg is required ~or clea~up complete~ess inspectiorlc.
For spill clean-up ~for~s, sophis~icated laboratory equipme~t is either brought to the spill site for sampling or the samples are sent to a cel~tral laboratory. Ill the first case, use of the portable gas chromatogra~ requires speaal operator training. In the secoIld case, the sample's trip to the laboratory takes time. Often the spill is rec~uired to be cleaned up before any a~al~cal results can be retu~ed from the lab, resul~ing in costly clean-up or missed spots.
29 The clean~up of spills of insulating liquids for tr~sformers and cap2citors would be better accomplished thr~ugh a system which pro~ides the ability ~o easily and co~cisely map ~he boundaries of a spill occurring on surfaces such as asphalt, concrete, grass and dirt and wet surfaces. Moreover, a system providing a real-time picture monitor of deanup efforts could facilitate useful information gathering. Furthermore, a system which does not require time co~sumi~g sampling procedures during clean-up completenessinspections could provide for more efficient and thorough spill cleanup operatioIls.
Therefore, there is a need for a real-time, user *iendly system for distin~uishing the spill from the non-spill area.

-2- ~
Accordingly, in an attempt to achieve the above objects, a real-time monitor system has bee~ developed which provides an operator the ability to see ~luorescent emissions of a spill ;n order to map out its boundaries. An excitation source lamp is used to induce fluorescent ernissions by the insulating liquids. The boundaries of the spill are mapped S by placement of markers according to detected ermissions made visible to a viewer on a video display monitor. The system operates so that a first and second detector generate ir~ages which may be received by a first mor~itor and/or second monitor.
The real-tirne monitor syste~n described above experieIlces interference of the emission signals in that their detection is influenced by the sun's radiation. A mobile box style sun Uock has been used for shielding the W radiation from the sun for daytirne ope-ration. Because a sun block shield or tent is ~umbersome, the system does not allow the user to easily and quickly map the spill. Moreover, the system of the prior art does D.Ot include means for intensifying and gating the fluorescent emissions of the spill con~ents necessary to avoid this solar interference.
lS Objects and Su~rnarv of the Invention It is therefore a general object of this invention ~o provide an improved fluorescence video monitor system for disting~ishing the spill from t~e non-spill area.
It ~ another object of the inve~tio~ to provide a real-time fluorescent video ima~g systern which may be used in the daylight.
It is also an object of the invention to provide a system which avoids illfluence from the source of e~citation light in the recepuon of the emission signals.
It is a further object to provide an e~atation source which operates at wavelengths providing optimixed lquOreSCerlt emsssions of most ~nsulat~ng liqu~ds and a detector which receives ~he fluorescene emission signals at their optimiæd wavelengehs.
It is still another object to provide a system tO allow the operator to better map the bou~ ies of a spill occurring on surfaces such as asphalt, concrete, metal, grass and dirt and wet surfaces by providing a means for distinguishing the fluorescent emissions of the spill contents from the surrounding environmenc.
Another object is to have at least two detectors, a first for viewing fluorescent emissions and a second for viewing the normal video irnage and means to s~,viech between their transmissions at a monitor and audio input for coordination of ehe documentation process of the clean-up.

The foregoing and other objects of the invention are achieved by a real-time fluorescence imaging system for.detecting the presence and boundaries of spiLls of insulating liquids for transformers and capacitors or other fluorescing materials. The system provides a two dimensional image of the spill having excitation means positioned 5 near the spill for producing fluorescent emissions of tbe insulating liquids, image intensification means for intensi*ing the fluorescent emissions, first detection means positionable to detect intensified fluorescent emissions from the insulating liquids and generating a detection signal, and display means for receiving the detection signal and generating a real-time video image of the presence and boundaries of the spill. The present 10 invention ~Iso includes pulse means for causing the excitation means to periodically excite fluorescent emissions from the insulating liquids and control means for controlling the intensification means to intensify only during periods of fluorescent excitation.
The excitation means is an optically filtered lamp bulb providing wavelengths ofbetween approximately 190 nm to 350 nrn for exciting fluorescent e nissions of said 15 i~ting liquids having a roughçned or smoothed surface and an alumiDized coating - over the roughened surface except for the transparent hole where the light is emitted.
The fluorescence detection means is sensitive at wavelengths between 340 nm and 450 nm in chosen (narrow 10 nrn) bands. Purthermore, the method of providi~g a real-time fluores,cenceirnagingsystemincludesthestepofapplyinganabsorbent/adsorbingpowder 20 to the area of the spill to absorb~adsorb insulating liquids from the underlying ground to concentrate the insulating liquids at the ground's surface. Also provided are switching means for allowing a viewer of the display means to view images from both a first detection means and a second detec~ion means. The second detec~ion means observes the overall Yideo image of the spill area to allow correla~ion of the analyzed image and 25 first detector's position and viewing area ~ear it.
Brief ~escription of the Drawin~s Other objects and many of the intended advantages of this invention will be readily appreciated as the same becomes better understood by reference to the following detailed description when considered in connection with the accompanying drawings, 30 wherein:
FIGURE 1 sho vs the basic components of a fluorescent monitoring system;
FIGURE 2 is a block diagram of the invention;

CA 2 1 ~ 73~

4 PCr/US92/11344 FIGURE 3 shows an aluminum coated light source havin~ an openiDg.
Detailed l:)escriptionQ~thç InventiQn Referencewill nowbe made in detail to the preferred embodiments of the invention, e~amples of which are illustrated in the accompa~ying drawi~gs. While the invention will be described in conjunction with the preferred embodiments~ it will be understood that they are not intended to limit the invention to those-embodiments. On the contrary, the in~ention is intended to cover alternatives, modifications and equivalents, which may be included within the spirit and scope of the invention as def~ned by the clairns.
Attention is drawn to FIG. 1 showing the basic components of a fluorescent moni-10 toring system. The spill 11 is illurninated by an easily positionable source lamp 12. Anoperator positions the detector 13 to receive fluoressent ernission signals excited in the spill by lamp 12 and generates video signals. The spill 11 of insulating liquids for transformers or capacitors which are mineral oil and askarel materials (PCBs), are considered hig~ly toxic or regulated. Such liquids include oil based liquids arld silicon 15 basedliquids, among others. Therefore, i~ediate cleanup of the spill siteis imperative.
Otller fluoresang materials such as gasoline spiLls or fuel oil spills may be analyzed in ~he s~me m.an~er.
The detçctor 13 se~ds the video signalk to a video moI~itor 14 at the back of detector 13 w~ich is in close proximity to the operator to display the received image. The e~cita-20 tion source 12 and detector 13 may be irlcorporated ~nto a s~ngle u~t as shown for easeof haIldling. The source lamp 12 is powered by battery 16 and detector 13 a~d monitor 14 are powered by a belt mounted battery 17. Belt mounted power has also been used to power the source.
Non-fluorescent images may be detected at a remote location by a remote s~cond 25 detector 21 and may be viewed Oll a remote second mor~itor 18 via r.f. transmissions 19. This information link can also be made by cable. Furthermore, the images from the second detector 21 may also be viewed by the operator at the first mor~ tor 14 or directed to the VCR.
The present system allows an operator to differentiate spill areas from non-spill areas 30 and to compare areas of lower and higher spill concentration in addition to de~ermining the spatial e~tent of tbe spill. Under field conditions, the spill may be in tbin layers, and therefore, tbe intensity of the fluorescence varies according to bulk tbickness. Combi-~`~ 93/13404 PCI/US92/11344 natio~s of properties such as the absorption coefficient at the excitation wavelength aswell as scattenng proper~ies of the background materials make a difference in t~e abili~y of the system to disc~minate the spill edge.
Turning tO FIG. 2, the lamp source 12 provites an ultra-violet emit~ing optical S excitation source which causes the PCB mineral oil or other spilled material to fluoresce and emit fluorescent light to emanate from the spill 11; A material fluoresces when its molecules or atoms absorb electromagnetic energy, and then r~emits this energy as electromagnetic radiation. The excitation energy used tO pllmp Up the molecule is generally at a higher electromagnetic energy, or shorter waveleng~h than the emitted 10 radiation. Electromagnetiç energy is inversely related to the wavelength of the light for both the excitation and the emitted wavelengths. Fluorescence is an inherently inefficient process and only a small fraction of the energy originally directed tO excite the sample is emitted as fluorescence.
The lamp 12 induces optical output characteristics of the spill materials that ca 15 be tetected by an optically filteredvideo se)lsor 13. The intensifier31 ;Idded tO the frorlt of the detec~ion sensor i~lt nsi~ies the signals of the fluorescence which are strong enougll to be observable by the sensor alone only when the typical spill is thick. The intensifier 31 has the added property that it shifts the sensitivity further into the W region th~n the video sensors' opera~ional range. The optical filtering eliminates much of the 20 interfering radiation by narrowing the ob~ervation window to the wavelengths of interest.
The optical filteling is not complete enough in eliminating i~ter~erence to the minimum leveLs.
To overcome the effects of additional inference, from the SUD in particular, theinte~ ier 31 provided is a gated unit. This gating periodically limits the signal input 25 in time SQ that the vast majority of the solar emissions (which are continuously present~
are excluded from the detection unit. The intensifier 31 is synchronized with the sour~e lamp 12. When the source flash occurs, nearly all of the fluorescent output from the spill ernanates from the spill during the same time period that the gate is open. The source lamp 12 of this invention is pulsedperiodically to excite the fluorescent emissions 30 in the spill by pulse means 32.

CA211/34~
WO g3/13404 PCI/US92/11344 ' The gated im~ge intensifier 31 and its synchronization with the trigger pulse means 32 of the source lamp 12 which is effected by synchronization me~s 33 is prmided by any suitable electronic circuit configuration.
The fluorescent emission signals genera~ed by the insulating liquid are intensified 5 by intensifier 31 so that the signals received by a detector can readily be converted to a real-~ime display apparatus. Intensification of the collected signal is accomplished by using a microchannel plate photon multiplication of the incidence photons to produce and image about 10,000 ti nes stronger than the incident ene~r. This energy is then projected onto the sensing elements of the detector 13, which is a GCI) carnera or vidicon 10 camera. The in~ensifier chosen for this application possesses coatings to enhance W
detection, a quartz ~rindow, and operates in gated mode for interference rejection.
The construction of the image intensified optical collection system 31 and 13 includes a 2.54 cm diameter quartz lens for collection of the radiation emitted from the sample.
The optical strength of the lens is fi1.5. This strength and size are nominally optimum 15 for proje~ion onto aIl intensifier having an 1 8-mm cathode, w~i~e providing a convenient field of viewforthe operator. The high magnification properties of the f/1.5 lens allows coll~on of the li~ht from a wide field of view. This single leIis lowers cost because the typical quartz camera unit uses a lens overspecified in optical resolution for this application. This ~pplication only requires a low resolution image. By using a lens of 20 a 2.54 cm diameter with a f/1.5 collection, the observation area is about 1 m2 in the field of view during a measurement at a conve~ient observation distance.
In ~he detection unit 13 there is also another lens. It has a small but high throughput image transfer lens and is used to direct the output of the imige intensifier phosphor screen to place the ~ge on the sensing elements. The placement and focusing proper~ies 25 of this lens allow the sample image to be reduced to the size of the sensing elements.
Thewa~elengths at which the excitation source operates depend on the light source, the optical filtering, and the material being observed. The type of insulating liquids or other fluorescing material forming the spill is determined in the typical manner, such as checking records or by other tests. In the present case, the material being observed 30 typically comprises oil and PCBs in varying proportions. Therefore, both the oil and the PCBs must be considered in choosing the excitation wavelength. Any means forachieving the excitation wavelengths are within the scope of the present invention.

`CA21 1 7345 93/13404 Pr/USg2/11344 The fluorescerlt excitation range of mineral oil is in the range of 190 ~m tO abQUt 340 nm. IJ1 PCB contaminated insulating liquids, the mineral oil is the predorninantly detected component because it is carried with the PCB irnpurity. Ma~imum sensitivity for mineral oil atation requires excitation below 280 nm, which is the condition which 5 applies when the system operates using a mercury e~citation source having an excitation wavelength of 254 nm. The s~e waveleIlgth can also be obtained with other sources such as an optically filtered xenon source.
With a very strong 254 llm line, the mercury larnp emits energy for excitation.
The mercury source is a line source and needs no optical filtering. The output is sufficient 10 fore~citation of apredorninantly mineral oil-basedinsulatingliquid. Fluorescence output for mineral oil is greater for this excitation than ~rhen excited at 300 or at 325 nm which spans a range of other available mercury lines.
The sun-excluding properties of the pulsed and optically filtered xenon source make it an atequate pulsed source for the mineral oil, PCB materials and a wide variety of 1~ other ~uorescing species such as gasoline and fuel oil. The xenon source is filtered to yield maximum excitation output between 230 Ilm and 350 nm using a commercially alrailable filter (SolarBlind Pilter) having a 8~ nm bandwidth with transmittance centered at 290 nm. A double thickness of a commercially available filter (Corion SB-300-F) is used for a thickness of 13 nm. This causes a sharper cutoff of the energy at about 325 20 nm rather than extending to 350 nm as in the commercial specificatio~ of the single ~hickness. A custom filter with similar bandwidth cutting off 10 rlm lower in wavelengths would be optim~m.
ita~on of the PCB materials produces ~um de~ctability when the e~tation ~ imum is near 300 nm. l'he mercury lamp having an output of 302 ~m and 313 nm 25 can be used, but these mercury lines are inherently weaker than the filtered xenon.
Coa~ings that shift the output of the strong mercury lamp line at 254 nm to 300 nrn are available but typical comrnercial available lamps cause interferences that lower sensitivity of the systern to PCB, the xenon-pulsed source is preferred for the detection of PCB
insulating materials. The commercially available filter (Solar ~lind ~ilter) discussed above 30 is used to obtain the maximum excitation with the xenon lamp near 300 nrn that is necessary.

CA~ 1 1 ;7345 WO93/l3404 P~/US92/11344 Observation wavelengths are also dependellt on the optical filtering used in theexcitation. The filter used is nominally 10 nm wide in tr~srnittance. Observation is performed generally below 420 nm because of the lower presence of ellergy in the sun and other visible light sources, although some fluorescence ener~y from the mineral oil 5 and PCBs extend above this level. Because of the blockage of interfering radiation, the pulsed xe~on source system is preferable.
Observations should be in a bandwidth in the range above 325 nm but may extend over 200 nrn above the excieation frequency because the mineral oils and PCB materials emit fluorescent energy in this wide band. The strongest emissions for the PCBs are at about 340 tO 410 nm using excitation at 280 nm tO 325 nm. For miLlLeral oil-based systems ~ith or without PCBs, the peak of the ernission is near 350 nm, however still strong at 380 nm.
Observation is usually made at 350 nm for the mineral oil-based liquid when excited by the mineral oil source. Mercury line interference are avoided while deteetion is-at 15 ~he fluorescence peak. Observation bandwidth therefore is 10 nm.
Due tO the interferences of the source, observa~ions are made at 380 ~m when the~enon lamp is used for either liquid. At approximately 350 nm, the system avoids most other interferences in the environment. Operation at this waveleIlgth requires a change in the excitation filter that blocks out the energy 10 nm lower than ~e 330 nm, which 20 is commercially available.
An al~um coating 43, as shown in Figure 3, on the bulb 40 of the source lamp 12 enables the bulb tO be operated with an increased e~ergy output. A second improv~
ment of the source lamp 12 consists of the surface 41 of the bulb 40 being roughened (egcep~ for the clear opening 42 of ~bout 1.27 cm in the front of the bulb 40~ before 25 applicauon of the aluminized coating 43. The roughening provides scattering surfaces in the alu~zed surface by which the light changes directions more randomly so that the light energy leaves the bulb 40 through the non-aluminized quartz opening 42 before being absorbed by multiple reflections and transmissions.
A method for enhancement of the fluorescent emissionsinvolves the step of applying 30 an absorbent powder to the area of the spill to absorb insulating liquids from the underlying ground to concentrate the insulating liquids at the grounds surface. The signal V ? 93/l3404 PCI`/USg2/l 1344 from the spill is enhanced by spreading sorbent material such as dehydrat~d GS04 having the ability to absorb the PCB or the mineral oil onto its surfaces.
The absorbent/adsorbent powder pulls rnaterial out of its original area of deposit.
Moreover, the successful material allows a certain amount of transfer of the excitation S light into the interstitial areas and also allows the light to transfer out of the material because of bigh reflectance in the amorphous state. Furthermore, unreflected energy is transmitted illtO the rnaterial, not absorbed, and therefore available to in~eract with spill material when it is re-emitted and reflected again into the interstitial areas, allowing additional interactions in the wavelength regions that coincide with the additional PCB
10 materials that are pulled up. The effect is that the layer of observation is spectroscopically thicker than the actual surface. Different materials having the same properties as CaS04 or different properties, including but not limited to CaO, MgSO~ and AlO may also be used.
By viewing both the first detector's video image of fluorescence and the second lj tetector's normal video image simultaneously, for example, on a split screen, the ability to map out the boundaries of the spill is enhanced because the fluorescent image can be compared with normal image. By con~inu~usly monitoring cleanup e~forts, the present . SySteIIl provides cost efficierlt clean-ups in that e~tra area is llOt take~l ineo the original dean up area. Part of the methodology in this case is tO observe successive layers for 20 contamination SpQtS as the previous layer is removed.
As described above with reference ~o FIG. 1, the images recei~ed by the second detector 21 for viewing the normal video image may be sent to the first monitor 14 on VCR 1~ ~y r.f. transmission or by cable. Switching means 34 for allowing a viewer of the first monitor or the second mor~itor to view images of both the first detector 13 and 25 the sesond detector 21 are provided by any suitable elestro~ic sonfiguration. Based on either simultaneous or back-to back s~bservations, the operator or a helper may plant markers around the edge of the spill at or outside its perimeter. Pa~h 36 bypasses the switching means 34 in the event use of the switching means 34 is not desired.
The images viewed OIl monitors 14 and 18 can be recorded with a VCR unit 15 30 which stores thern for future viewing. Recording the images on tape serves two purposes.
First, it allows to replay the observations, providing infoImation for the personnel cha~ed with clean-up of the spill; and second, it provides documentation of the work accom-CA2~ ~ ~34~
WO 93/13404 PCI/US92/~ ff~

plished for later review. Moreover, a audio amplification sys~em to amplify sound from a microphone used in documentation on the YCR tape or second sound recording system is also beneficial to the spill clean-up process. If recording is not required, VCR 15 can be bypassed by paths 37 and 38, indicated by dotted lisles on Figure 2. Fu~thermore, 5 if recording is desired, paths 37 and 38 may be used as secondary information paths while the VCR 1~ is in use.
Clearly, the general object of this invention to pro~nde an improved system for distinguishing` the spill from the non-spill area has been met. Moreover, the object of ~he inven~ion tO provide a real-time fluorescen~ video imaging system which may be used 10 in the daylight has also been met. Also, the object of the inven~ion tO provide a system which avoids influence from the source of excitation light in the reception of the emission signals has been met as has been the object to provide an excitation source which operates at wavelengths providing optimized fluorescent emissions of mos~ insulating liquids and a detector whicb receives the fluorescent emission signals at their optimized waveleng~hs.
1~ Furthermore, the obj~ct to provide a system to better map the boundaries of a spill occurring on surfaces such as asphalt, concrete, metal, grass a~d dirt aIId wet surf~ces by providing a means for distin~hing and eDhancing the fluorescent emissions of the spill contents has been met. Finally, the object to have at least two detectors, a first for vie~,ving fluorescent eni~ssions and a second for viewing the noImal video image and means 20 to switch between ~heir transmissions at a monitor has been met.
While this invention has been shown and described in what is presently conceivedto be the most practical and preferred embodiment of the invention, it will become apparent ~o those of ordinary skill in the art that ma~y modificatio~s thereof may be made ~v~thin the scope of the invention, which scope is to be acsorded the broadest 25 interpretation of ~he claims so as to encompass all equivalent structures.

Claims (24)

IN THE CLAIMS:

1. A portable real-time fluorescence imaging system for detecting the presence and boundaries on-site of a spill of a fluorescing species and providing a two dimensional image of the spill, comprising:
hand carried excitation means positionable near a spill for exciting fluorescent emissions of said fluorescing species;
pulse means for causing said excitation means to periodically excite said fluorescent emissions with pulsed periods of fluorescent excitation;
image intensification means for intensifying said periodically excited fluorescent emissions;
hand carried first detection means fixedly positionable for detecting said intensified fluorescent emissions and generating a first detection signal representing said intensified fluorescent emissions;
control means for controlling said intensification means to intensify only during said pulsed periods of fluorescent excitation so that a majority of any interfering emissions are not detected by said first detection means;
display means for receiving said first detection signal and for generating from said first detection signal a real-time fluorescent video image of the presence and boundaries of said spill.

2. A portable real time fluorescence imaging system for detecting the presence and boundaries on-site of a spill of a fluorescing species and providing a two dimensional image of the spill, said system comprising:
hand carried excitation means positionable near a spill for exciting fluorescent emissions of said fluorescing species;

trigger pulse means for enabling said excitation means to periodically excite said fluorescent emissions;
and image intensification means for intensifying said periodically excited fluorescent emissions;
hand carried first detection means fixedly positionable for detecting said intensified fluorescent emissions and for generating a first detection signal representing said intensified fluorescent emissions;
display means for receiving said first detection signal and for generating from said first detection signal a real-time fluorescent video image of said detected fluorescent emissions;
synchronization means for synchronizing said trigger pulse means and said image intensification means so that a majority of any interfering emissions are not detected by said first detection means.

3. A system as recited in Claim 1 or 2 wherein said fluorescing species is an insulating liquid.

4. A system as recited in Claim 1 or 2 wherein said fluorescing species contains PCBs.

5. A system as recited in Claim 1 or 2 wherein said excitation means includes a light bulb providing excitation within wavelengths of between approximately 190 nm to 350 nm for exciting said fluorescent emissions.

6. A system as recited in Claim 1 or 2 wherein said excitation means includes a mercury lamp.

7. A system as recited in Claim 1 or 2 wherein said excitation means includes a xenon lamp.

8. A system as recited in Claim 1 or 2 wherein said detection means is sensitive to wavelengths between approximately 325 and 450 nm.

9. A method for providing real-time on-site fluorescence imaging for detecting the presence and boundaries of a spill of a fluorescing species and for imaging detection signals in two dimensions, comprising the steps of:
positioning a hand carried excitation source near said spill;
fixedly positioning a hand carried detector near said spill;
with said hand carried excitation source, periodically exciting fluorescent emissions of said fluorescing species with pulsed periods of fluorescent excitation;
intensifying said fluorescent emissions only during said pulsed periods of fluorescent excitation so that a majority of any interfering emissions will not be detected, with said hand carried detector, detecting said intensified fluorescent emissions;
displaying a real-time fluorescent video image of said detected fluorescent emissions.

10. A method as recited in Claim 9 further comprising the step of applying an absorbent powder to the area of said spill, said absorbent powder absorbing said fluorescing species from the underlying ground to concentrate said fluorescing species at the ground's surface for increased excitation of said fluorescent emissions, said absorbent powder also reflecting some of said fluorescent excitation onto said spill so as to excite said fluorescent emissions even further.

11. A method as recited in Claim 9 wherein said fluorescing species is an insulating liquid.

12. A method as recited in Claim 9 wherein said fluorescing species contains PCBs.

13. A system as recited in Claim 1 or 2 wherein:
said display means is also for receiving a second detection signal of a normal image of said spill, for generating a real-time normal video image of said spill, and for allowing correlation of said fluorescent video image with said normal video image for mapping the boundaries of said spill;
said system further comprising:
second detection means positionable for detecting said normal image of said spill and for generating said second detection signal.

14. A system as recited in Claim 1 or 2 wherein:
said display means is also for receiving a second detection signal of a normal image of said spill, for generating a real-time normal video image of said spill, and for allowing correlation of said fluorescent video image with said normal video image for mapping the boundaries of said spill;
said system further comprising:
second detection means positionable for detecting said normal image of said spill and for generating said second detection signal; and switching means for allowing a viewer of said display means to view on command said fluorescent and normal video images simultaneously for said correlation of said fluorescent video image with said normal video image.

15. A system as recited in Claim 1 or 2 wherein:

said display means is also for receiving a second detection signal of a normal image of said spill, for generating a real-time normal video image of said spill, and for allowing correlation of said fluorescent video image with said normal video image;
said system further comprising:
second detection means positionable for detecting said normal image of said spill and for generating said second detection signal; and switching means for allowing a viewer of said display means to view on command said fluorescent and normal video images back to back for said correlation of said fluorescent video image with said normal video image.

16. A system as recited in Claim 5 wherein said light bulb has:
a roughened surface except for an opening of approximately 1.27 cm in diameter through which light passes; and an aluminized coating over said roughened surface.

17. A method as recited in Claim 9 further comprising the step of detecting said normal image of said spill;
said displaying step including displaying said real-time normal video image of said spill and allowing correlation of said fluorescent video image with said normal video image for mapping the boundaries of said spill.

18. A method as recited in Claims 14 and 23 wherein said powder comprises CaSO4.

19. A real-time fluorescence imaging system for detecting the presence and boundaries on-site of a spill of a fluorescing species and providing a two dimensional image of the spill, comprising:

excitation means positionable near a spill for exciting fluorescent emissions of said fluorescing species;
pulse means for causing said excitation means to periodically excite said fluorescent emissions with pulsed periods of fluorescent excitation;
image intensification means for intensifying said periodically excited fluorescent emissions;
first detection means positionable for detecting said intensified fluorescent emissions and generating a first detection signal of said intensified fluorescent emissions;
second detection means positionable for detecting a normal image of said spill and for generating a second detection signal representing said normal image;
control means for controlling said intensification means to intensify only during said pulsed periods of fluorescent excitation so that a majority of any interfering emissions are not detected by said first detection means;
display means for receiving said first and second detection signals, for generating from said first detection signal a real-time fluorescent video image of the presence and boundaries of said spill, for generating from said second detection signal a real-time normal video image of said spill, and for allowing correlation of said fluorescent video image with said normal video image for mapping the boundaries of said spill.

20. A real-time fluorescence imaging system for detecting the presence and boundaries on-site of a spill of a fluorescing species and providing a two dimensional image of the spill, said system comprising:
excitation means positionable near a spill for exciting fluorescent emissions of said fluorescing species;

trigger pulse means for enabling said excitation means to periodically excite said fluorescent emissions;
and image intensification means for intensifying said periodically excited fluorescent emissions;
first detection means positionable for detecting said intensified fluorescent emissions and for generating a first detection signal representing said intensified fluorescent emissions;
display means for receiving said first and second detection signals, for generating from said first detection signal a real-time fluorescent video image of said detected fluorescent emissions, for generating from said second detection signal a real-time normal video image of said spill, and for allowing correlation of said fluorescent video image with said normal video image for mapping the boundaries of said spill;
synchronization means for synchronizing said trigger pulse means and said image intensification means so that a majority of any interfering emissions are not detected by said first detection means.

21. A system as recited in Claim 19 or 20 further comprising switching means for allowing a viewer of said display means to view on command said fluorescent and normal video images back to back for said correlation of said fluorescent video image with said normal video image.

22. A real-time fluorescence imaging system for detecting the presence and boundaries on-site of a spill of a fluorescing species and providing a two dimensional image of the spill, said system comprising:
excitation means positionable near a spill for exciting fluorescent emissions of said fluorescing species, said excitation means including a light bulb providing excitation within wavelengths of between approximately 190 nm to 350 nm for exciting said fluorescent emissions, said light bulb having a roughened surface except for an opening of approximately 1.27 cm in diameter through which light passes and an aluminized coating over said roughened surface;
trigger pulse means for enabling said excitation means to periodically excite said fluorescent emissions;
and image intensification means for intensifying said periodically excited fluorescent emissions;
detection means fixedly positionable for detecting said intensified fluorescent emissions and for generating a detection signal representing said intensified fluorescent emissions;
display means for receiving said detection signal and for generating from said detection signal a real-time fluorescent video image of said detected fluorescent emissions;
synchronization means for synchronizing said trigger pulse means and said image intensification means so that a majority of any interfering emissions are not detected by said first detection means.

23. A method for providing real-time on-site fluorescence imaging for detecting the presence and boundaries of a spill of a fluorescing species and for imaging detection signals in two dimensions, comprising the steps of:
periodically exciting fluorescent emissions of said fluorescing species with pulsed periods of fluorescent excitation;
intensifying said fluorescent emissions only during said pulsed periods of fluorescent excitation so that a majority of any interfering emissions will not be detected;
detecting said intensified fluorescent emissions and a normal video image of said spill;

displaying a real-time fluorescent video image of said detected fluorescent emissions and a real-time normal video image of said spill and allowing correlation of said fluorescent video image with said normal video image for mapping the boundaries of said spill.

24. A method for providing real-time on-site fluorescence imaging for detecting the presence and boundaries of a spill of a fluorescing species and for imaging detection signals in two dimensions, comprising the steps of:
periodically exciting fluorescent emissions of said fluorescing species with pulsed periods of fluorescent excitation;
intensifying said fluorescent emissions only during said pulsed periods of fluorescent excitation so that a majority of any interfering emissions will not be detected;
detecting said intensified fluorescent emissions;
displaying a real-time fluorescent video image of said detected fluorescent emissions; and applying an absorbent powder to the area of said spill, said absorbent powder absorbing said fluorescing species from the underlying ground to concentrate said fluorescing species at the ground's surface for increased excitation of said fluorescent emissions, said absorbent powder also reflecting some of said fluorescent excitation onto said spill so as to excite said fluorescent emissions even further.