ASTM_E_1809_-_01.pdf

Designation:E 1809 9601Standard Test Method forMeasurement of High-Visibility Retroreflective-ClothingMarking Material Using a Portable Retroreflectometer1This standard is issued under the fixed designation E 1809;the number immediately following the designation indicates the year oforiginal adoption or,in the case of revision,the year of last revision.A number in parentheses indicates the year of last reapproval.Asuperscript epsilon(e)indicates an editorial change since the last revision or reapproval.1.Scope1.1 This test method covers the measurement of the retroreflective properties of high visibility pedestrian garments,such asvests,using a portable retroreflectometer that can be used in the field.The portable retroreflectometer is a hand-held instrumentwith a defined standard geometry corresponding to United States usage that can be placed in contact with retroreflective markingmaterial to measure the retroreflection.The measurements can be compared to minimum requirements to determine the need forreplacement of the retroreflective material.1.2 This test method is designed for measuring retroreflective marking materials that have an area equal to or greater than thatof the aperture of the retroreflectometer.1.3 This test method is intended to be used for field measurement of retroreflective marking materials,but may be used tomeasure the performance of materials before placing the clothing in use.1.4 This standard does not purport to address all of the safety concerns,if any,associated with its use.It is the responsibilityof the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatorylimitations prior to use.2.Referenced Documents2.1 ASTM Standards:E 284 Terminology of Appearance21This test method is under the jurisdiction ofASTM Committee E-12 on Color andAppearance and is the direct responsibility of Subcommittee E12.10 on Retroreflection.Current edition approved May Dec.10,1996.2001.Published J February 2002.Originally published as E 1809-96.Last previous edition E 1809-96.1This document is not an ASTM standard and is intended only to provide the user of an ASTM standard an indication of what changes have been made to the previous version.Becauseit may not be technically possible to adequately depict all changes accurately,ASTM recommends that users consult prior editions as appropriate.In all cases only the current versionof the standard as published by ASTM is to be considered the official document.Copyright ASTM International,100 Barr Harbor Drive,PO Box C700,West Conshohocken,PA 19428-2959,United States.E 177 Practice for Use of the Terms Precision and Bias in ASTM Test Methods3E 691 Practice for Conducting an Interlaboratory Study to Determine the Precision of a Test Method3E 808 Practice for Describing Retroreflection3E 809 Practice for Measuring Photometric Characteristics of Retroreflectors2E 810 Test Method for Coefficient of Retroreflection of Retroreflective Sheeting23.Terminology3.1 The terminology used in this test method,in general,agrees with that used in Terminology E 284.3.2 DefinitionsThe delimiting phrase in retroreflection applies to each of the following definitions when used outside thecontext of this or other retroreflection standards.3.2.1 coeffcient of retroreflection,RA,nof a plane retroreflecting surface,the ratio of the coefficient of luminous intensity(RI)of a plane retroreflecting surface to its area(A),expressed in candelas per lux per square metre(cdlx1 m2).RA5 RI/A(1)3.2.2 entrance angle,bdatum axis,nangle betweena designated half-line from the illumination axis and retroreflectorcenter perpendicular to the retroreflector axis.3.2.3 entrance angle,b,nthe angle between the illumination axis and the retroreflector axis.3.2.4 entrance half-plane,nthe half-plane that originates on the line of the illumination axis and contains the retroreflectoraxis.3.2.5 instrument standard,na working standard used to standardize the portable retroreflectometer.3.2.46 observation angle,nthe angle between the illumination axis and the observation axis.3.2.57 observation half-plane,nthe half-plane that originates on the line of the illumination axis and contains the observationaxis.3.2.8 orientation angle,vs,nthe angle in a plane perpendicular to the retroreflector axis from the entrance half-plane to thedatum axis,measured counter-clockwise from the viewpoint of the source.3.2.9 portable retroreflectometer,na hand-held instrument that can be used in the field or in the laboratory to measureretroreflection.3.2.59.1 DiscussionIn this test method,portable retroreflectometer refers to a hand-held instrument that can be placed incontact with retroreflective marking material to measure the coefficient of retroreflection in a standard geometry.3.2.610 presentation angle,g,nangle betweenthe dihedral angle from the observation entrance half-plane and to thehalf-plane that originates on observation half-plane,measured counter-clockwis