University of Virginia)

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1 D. Shepard Frank Scientist Research opinions, findings, and conclusions expressed in this (The are those of author and not necessarily those of report Highway g Transportation Research Council Virginia Cooperative Organization Sponsored Jointly by Virginia (A of Highways g Transportation and Department University of Virginia) 1980 September 81-R15 VHTRC FINAL REPORT EVALUATION OF YELLOW-WHITE PAINT MIXTURES by sponsoring agencies.) Charlottesville, Virginia

2 H. E. PATTERSON, Senior Traffic Engineer, Norfolk Department MR. Public Works of TRAFFIC RESEARCH ADVISORY COMMITTEE MR. L. C. TAYLOR II, Chaimman, Distmic Tmaffie Engineem, VDHST MR. L. H. DAWSON, JR., Assist. Tmaffie $ Safety Engineem, VDHgT MR. J. B. DIAMOND, District Traffic Engineer, VDHgT MR. J. E. GALLOWAY, JR., Assist. State Materials Engineer, VDHgT DR. JAMIE HURLEY, Assist. Professor of Civil Engineering, VPI g SU MR. C. O. LEIGH, Maintenance Engineer, VDHgT MR. R. F. MCCARTY, Safety Coordinator, FHWA MR. J. P. MILLS, JR., Traffic g Safety Engineer, VDHST MR. W. C. NELSON, JR., Assist. Traffic $ Safety Engineer, VDHST MR. R. L. PERRY, Assist. Transp. Planning Engineer, VDHgT MR. F. D. SHEPARD, Highway Research Scientist, VHSTRC ii

3 study was initiated by Deputy Commissionem and Chief This Leo E. Busse III on basis of a Fedemal Highway Engineem Administmation (FHWA) mepomt suggesting that a substantial sav- agencies. A task force composed of W. C. Nelson, Jm., of om Tmaffic and Safety Division as chaimman, and Nomman E. Hood of Fmedemicksbumg Distmict, J. E. Galloway Jm. of Matemials and Fmank D. Shepamd of Reseamch Council was fommed Division, evaluate FHWA suggestion and develop mecommendations. The to was a joint effomt of membems of task fomce. study PREFACE could be mealized thmough substitution of diluted yellow- ings paint fom standamd yellow used by Depamtment and white This report was prepared by Research Council. iii

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5 view of potential cost savings to be achieved through In use of regular yellow traffic paint diluted with less white paint, it was decided that Department would expensive roadway applications of paint mixture with emphasis evaluate compatibility of Department's painting equipment and on with proposed paint mixture, motorist's re- procedures to diluted yellow color, and cost savings by using actions mixture. Conclusions and recommendations are presented based evaluation of two test sections in Fredericksburg on District. SUMMARY

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7 D. Shepard Frank Scientist Research Manual on Uniform Traffic Control Devices (MUTCD) requires The white lines be used to delineate separation of traffic that in same direction or mark right edge of pavement, flows that yellow lines be used to delineate separation of traffic and in opposing directions or mark left edge of pavement flows divided highways and one-way roads. These requirements have of considerable debate concerning relative visibilities of prompted and yellow pavement markings, especially at night and under white lighting and wear conditions. The Federal Highway Admin- adverse (FHWA) recently funded an investigation of. driver's istration As noted in report on investigation, replace- visible. of some of yellow pigment with white pigment could be ad- ment since yellow paint lines are initially less reflective vantageous white ones, and y darken considerably with exposure after tnan Also, because of ir lower brightness contrast with painting. pavement, yellow markings are typically not as visible as white adverse driving conditions of night lighting, rain, fog, and under degradation. From an economic standpoint, investiga- windshield indicated that a substantial cost savings could be realized by tion yellow paint with white paint to a 50" 50 pigment weight diluting view of potential cost savings to De achieved thm,ough In use of diluted yellow paint, it was decided that Depart- would evaluate roadway applications of paint mixtures spec- ment in FHWA report. ified purpose of this study was to investigate use of yellow- The paint mixtures for highway delineations with particular empha- white FINAL REPORT EVALUATION OF YELLOW-WHITE PAINT MIXTURES by INTRODUCTION requirements for roadway delineation with emphasis on visibility least proportion of yellow highway paint needed in determining yellow-white paint mixture for mixture to be identifiable as a yellow. The study concluded that yellow highway paint being used may be diluted up to 50% with white paint without loss of now identity for driving conditions under which color is normally color ratio. PURPOSE AND SCOPE sis on following"

8 motorists' reactions to diluted yellow color, (b) and cost savings that could be realized by using (c) mixture. evaluation was limited to comparisons of regular The and diluted yellow paints used for centerlines and edgeline yellow test sections in Fredericksburg District were selected Two application of yellow-white paint mixtures. One was for a section of Route 2 (2-1ane, bituminous.) between New Post 14-mile Bowling Green; or included Route 360 bridge (2-1ane and crossing Rappahannock River at Tappahannock. It is concrete) that both test sections were on rural highways with no noted contained 2 gal. of white paint and 1 gal. of yellow paint ture weight pigment ratio). The paints were applied to road (50"50 way in following manner. Where re were two adjacent lines, such as a skip I. next to a solid line or a double solid line, line line was painted with diluted paint and left line was painted with regular yellow. right Where re was only a single skip line, diluted paint 2. used. was To minimize influence of application equipment 3. adjacent lines, paint was switched half way on regular paint was applied on left. The bead were not switched. This permitted observation of guns compatibility of Department's painting (a) and procedures with proposed equipment paint mixture, on 2-1ane bituminous and concrete highways. PROCEDURE Test Sections lighting -exc ept vehicle lights. a tificial regular yellow paint was taken from stock and mix- The test section; i.e., on last half of through diluted paint was applied on right and section both paint stripes with same bead application.

9 The paints were applied using normal procedures; 4. rate was approximately 6 lb./gal, of i.e., on a paint film (dry) thickness of 13 to beads mils. 14 entire process was carefully monitored to determine The of equipment and procedures with diluted compatibility paint mixture and to note any problems encountered. paint. Comparisons were made through use of a ques- yellow given to Department personnel. The questionnaire was tionnaire out on two occasions and included ratings of stripes filled both daylight and darkness. under reference to Mr. Hood's memorandum included in Appen- With mixture of 2 gal. of white paint to I gal. of yellow paint dix, ideally suited for application with painting equipment used was Fredericksburg District. The capacity of paint tanks in equipment is 165 gal. Achieving proper ratio was simply on matter of placing two barrels of white paint and one barrel of a yellow paint in tank. a barrel of white, a barrel of yellow, and n Pumping barrel of white into tank resulted in a good mixing action, second roadway to be striped, paint was thoroughly mixed and ready of application. In summary, Mr. Hood offered following observa- for The mixing of paint poses no problem. It I. no great change in loading procedures requires and re is no added expense. Use of mixture will require close scheduling 2, supervisor, because all of paint in by must be used up before a new batch can be tanks To obtain 2 b rrels to i ratio, mixed. Evaluation of Color relative yellowness of stripes of diluted paint was The by comparing it to that of lines made with standard evaluated RESULTS Application Process noted by Mr. Hood. After tank was filled, mechanical agi- as were turned on. By time equipment reached section tators tions. full capacity of tank must be used.

10 questionnaires were filled out by Department per- Thirteen five upon installation of stripes and eight sonnel nine months afterwards. The questionnaire is shown approximately Table i along with percentages of responses to questions. in Can you detect differences i. yellow and between yellow lines? (Route diluted Bituminous) 2, broken (passing one b direction) broken (passing both c directions) Can you detect differences 2. yellow and between yellow lines? diluted Bridge, Con- (Rappahannock your opinion is In yellow line suffi- diluted yellow to be dis- ciently from white lines? I tinguishable Is diluted yellow line more 4. than regular visible yellow? close-up a Your general opinion concerning use of diluted yellow paint 5. centerline marking from standpoint of color (yellowness) for Que, s.,t ion_naim_e Su_ _vey Table i of Responses to Survey Questionnaire Percentages Post and Tapp.ahannock New Night Day Yes No Little Yes No ittle a- double solid ii crete) a- double solid b- faraway and visibility (brightness and distance).

11 Following ame commen s on he mesul s. Double solid" A large percentage (90%) of a- perceived a difference between respondents during daylight. At night, however, as paints did not detect a difference (27%) as did many (27%), and 46% saw little difference. Broken (passing one direction)" Eighty per- b noted a difference while 20% noted a minimal cent during daylight. At night, per- difference were same as for double solid marking; centages is, 27% noted a difference, 27% did not, and 46% that little difference. noted Broken (passing both directions)" During daylight 67% c y saw a difference, 11% did not see a difference, said 22% saw a minimal difference. During darkness, a and higher percentage noted no difference, 30% vs. slightly 20%, while 50% saw little difference. Can you detect differences in yellow and diluted yellow 2. (Rappahannock Bridge, Concrete) lines? respondents opined that while re was a difference Some shade, both lines were yellow. Also, some noted that it was in as easy to detect a difference at night as it was in not daylight. In your opinion is diluted yellow line sufficiently yellow 3. be distinguishable from white lines? o no difference at a glance; however, se evaluators could saw a difference upon observation. detect Can you detect differences between yellow and i. yellow lines? (Route 2, Bituminous) diluted respondents commented that, although it was difficult to Many a difference in color, diluted paint appeared detect to be a shade lighter. Double solid Ninety percent noted a difference during a day, while at night 64% noted a difference, and anor 27% noted a slight difference. thought re was a difference during day, Everyone 91% could distinguish a difference at night. Nine percent while

12 diluzed yellow line mome visible than megular Is yellow? not, and 23% noted a minimal difference. At did opinions were evenly divided; 36% thought night, diluted yellow line more visible, and an equal thought it was not. percentage Faraway" Under daylight 56% thought diluted lines b be more visible, 22% saw no difference, and 22% saw to minimal difference. At night, 55% thought diluted a was more visible, 27% did not, and 18% thought paint is more visible in wet wear. Diluted coler is as good as or. One could be used. Diluted difference in lines. Minimal difference at night; more difference in day; Little daylight not as critical. however, should be acceptable as a substitute for Diluted yellow. regular bead application rate is equal, diluted yellow When fine. shows is noted that on one occasion six observers viewed test It on bituminous pavement during wet conditions at night. It( section to observe any difference between colors of pavement was markings. i through 5 are photographs of diluted and standar- Figures on test sections. paints Close-up" Forty-four percent thought diluted a was more visible during daylight, 33% yellow re was little difference. Your general opinion concerning use of diluted yellow paint 5. centerline marking from standpoint of color (yellowne ) for and visibility (brightness and distance). The comments can be summarized as follows" to tell differences between colors in sun. Difficult paint is yellower and brighter. Diluted Diluted yellow will work. general consensus that heavier rain, and refore was greater film of water on lines, more difficult it

13 i0 Close-up of test plates showing regular yellow, Figure on and diluted yellow. left, 2. Double solid line on bituminous pavement. Regular Figure on left. yellow

14 Figure 8. Passing, one direction, on bituminous pavement. Figure. Double solid line on bituminous pavement at night.

15 estimate of cost savings realizable through using An yellow paint was made by taking amount of yellow paint diluted paint used annually 28,000 al. Yellow paint used annually $ 0,000 zal. White yellow paint $.60/ ai. Cost white paint $%.05/ ai. Cost cost/yr, 248,000 gal. x $4.60 $1,306,400 : Total yellow white 340,000 gal. x $4.05 $1,377,000 = cost/yr, Total S. Double solid line on concrete pavement. Figure yellow on right. Regular Cost_ Sav_ing s.. used in state last year and projecting a cost based on present paint prices. Present Total Annual Cost Total cost of paint $2,683,400

16 ec, ted _Co.st usi.n.g D..i.luted.. Y.e.l.lo P r.0.j x 284,000 gal. = 189,332 gal. 2/3 x 284,000 gal. = 94,667 gal. i/3 white normally used" Amount yellow used afte# dilution Amount white 529,332 gal. x $.05/gal. Cost yellow = 9,667 gal. x $.60/gal. Cost cost paint using diluted Total befo#e dilution Cost after dilution Cost Yearly savings using diluted on yellow paint: Savings yellow Cost cost yellow Extma cost of diluted Total if all white, 62 gal. x $4.05/gaI. Cost cost when using diluted Extma cost yellow Extra cost using diluted Extra Savings using diluted $1,306,400 2 o o.o,, 156,200 $ $2,579,263,200 $2, ,063 $ gal. 340,000 gal. 189,332 gal. 529,332 gal. 94,667 $2,143, ,468 of extra cost of using standard yellow can be saved Percentage diluted yellow" i04,137/156,200 67%. using is, refore, estimated that an annual cost savings of It can be realized if diluted yellow were substituted for tht $104,137 yellow. This figure reflects a savings of 3.9% of total regular of all paint used and a 67% savings of extra cost of using cost Amount white replacing yellow (diluted)" $2,579,263 $2,683,400.$2, 79,263 $ i04,1 7 Cost I04,_137 $ 2,683,q O0 3.9% Savings Savings on all paint (white and yellow) Cost white equal amount $156,200 5,:,,063 $ 8104.,137 yellow. i0

17 on results of this study, application of Based paint with existing equipment and procedures presents no diluted yellow paint with present equipment will require close diluted by supervisor to ensure that all paint in scheduling two questionnaire surveys revealed that differences in The of yellow could be detected during day, but that it was shade to detect differences at night. Also, it was found that difficult diluted yellow line was sufficiently yellow to be distinguishable white lines. Opinions were mixed on ability to detect dif- from in visibility, both close-up and faraway. 0verall, ferences cost estimates indicate a substantial savings in Preliminary cost of paint should Department change to diluted yellow. 3.9 of total cost of all paint used and 67 of Approximately extra cost of using standard yellow could be saved using is recommended that if permission can be received from It for placement of diluted yellow instead of regular FHWA of using it before considering application on a statewide advantages basis. CONCLUSIONS AND RECOMMENDATIONS The mixing and loading procedures presented no problem problems. re was no added expense. It is noted, however, that using and tanks is used before a new batch can be mixed properly. revealed that although differences were noted in rela- surveys degrees of yellowness of standard yellow and diluted yellow, tive diluted was still yellow, differences in shades of yellow minima and diluted should be acceptable as a substitute. were diluted yellow. diluted paint should be tried in entire Fredericks yellow, District to gain more knowledge of advantages and any dis- burg ii

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19 A Report On The Use of Diluted SUBIECT: Traffic Zone Paint In The Yellow Fredericksburg District.,. O [l rrnno. 22-A July I0, 19 recent months interest has been generated in use of diluted yellow In zone paint. This interest centers on honest attempts by managers traffic make tax dollar do a more efficient job. With cost of every- to escalating so rapidly, it is vitally necessary that this be done. thing order to determine if a savings could be effected by use of this In paint, it was decided to make a test application in Fredericks- diluted District. It had to be proven that dilution of paint would burg significantly alter performance of material. not sections of roadway were selected for this performance evaluation. Two was a stretch of Route 2 between New Post and Bowling Green. This One of Route 2 is approximately 14 miles long and is in Caroline and section sylvania Counties. Spot mixture decided upon was a 2 to i ratio; i.e., two gallons of white The to one gallon of yellow paint. This ratio was ideally suited to paint painting equipment presently being used in Fredericksburg District capacity of paint tanks on existing equipment is 165 gallons. The proper ratio was simply a matter of putting 2 barrels of Achieving paint and i barrel of yellow paint in tank. white paint was pumped into tank in sequence of a barrel of white, The barrel of yellow, and n second barrel of white. This method reached section of roadway to be painted, paint was equipment mixed and ready for application. thoroughly Where re were two adjacent lines, such. as a skip line i. to a solid line or a double solid line, left next was painted with diluted paint and right line was painted with regular traffic zone yellow. line Where re was only a single skip line, it was painted 2. diluted paint. with APPENDIX DEPARTMENT OF HIGHWAYS MEMORANDUM INTER.DEPARTMENTAL Fredericksburg TO Vir ini 80 FROM Mr. Norman E. Hood Route Proj in a good mixing action. After tank-filling operation was resulted mechanical agitators were turned on. By time completed, The paint was applied to roadway in following manner"

20 Page 2 continued In order to assure proper evaluation of bead 3. and retention, approximately half distribution through test section, paint was way i.e., diluted paint was put on switched, side and regular paint was put on right side. The bead guns were not switched. This left permitted eval a io -6f 6th"' inds of procedure with identical bead application. paint Samples of each paint and method of application 4. obtained by placing aluminum strips in were in path to be painted. These samples roadway retained for laboratory evaluation. were Since application, several inspections, during 5. night and day, have been made of two test both The diluted paint is readily recognizable a. yellow paint. as There is no apparent excess spailing of beads b. diluted paint. In my last inspection from test areas, July 2, 1980, bead re- of of diluted paint was equal to tention retention capability of undiluted bead paint. Use of diluted paint will require close scheduling 2. supervisor in that paint truck must be by "painted out", or all of paint in completely must be used up, before a new batch can be mixed, tanks to obtain proper 2 to i ratio, full because of tank must be used. capacity It is my recommendation that Fredericksburg District 3. permitted to run a pilot program and use diluted be areas with following results" As a result of my participation in this evaluation, I offer following" The mixing of paint poses no problem. It requires i. great change in loading procedures. There is no no added expense. district-wide for a period of one year. With proper paint keeping, this should allow proper evaluation of record co.st savings that might result from its use. NEH/gf