1、 ANSI/ESD STM4.1-2017 A revision and redesignation of ESD S4.1-2006 For the Protection of Electrostatic Discharge Susceptible Items Worksurfaces Resistance Measurements (Including Shelving and Mobile Equipment) Electrostatic Discharge Association 7900 Turin Road, Bldg. 3 Rome, NY 13440 An American N
2、ational Standard Approved February 27, 2018 ANSI/ESD STM4.1-2017 ESD Association Standard Test Method for the Protection of Electrostatic Discharge Susceptible Items - Worksurfaces Resistance Measurements (Including Shelving and Mobile Equipment) Approved September 7, 2017 EOS/ESD Association, Inc.
3、ANSI/ESD STM4.1-2017 Electrostatic Discharge Association (ESDA) standards and publications are designed to serve the public interest by eliminating misunderstandings between manufacturers and purchasers, facilitating the interchangeability and improvement of products and assisting the purchaser in s
4、electing and obtaining the proper product for his particular needs. The existence of such standards and publications shall not in any respect preclude any member or non-member of the Association from manufacturing or selling products not conforming to such standards and publications. Nor shall the f
5、act that a standard or publication that is published by the Association preclude its voluntary use by non-members of the Association whether the document is to be used either domestically or internationally. Recommended standards and publications are adopted by the ESDA in accordance with the ANSI P
6、atent policy. Interpretation of ESDA Standards: The interpretation of standards in-so-far as it may relate to a specific product or manufacturer is a proper matter for the individual company concerned and cannot be undertaken by any person acting for the ESDA. The ESDA Standards Chairman may make co
7、mments limited to an explanation or clarification of the technical language or provisions in a standard, but not related to its application to specific products and manufacturers. No other person is authorized to comment on behalf of the ESDA on any ESDA Standard. THE CONTENTS OF ESDAS STANDARDS AND
8、 PUBLICATIONS ARE PROVIDED “AS-IS,” AND ESDA MAKES NO REPRESENTATIONS OR WARRANTIES, EXPRESSED OR IMPLIED, OF ANY KIND WITH RESPECT TO SUCH CONTENTS. ESDA DISCLAIMS ALL REPRESENTATIONS AND WARRANTIES, INCLUDING WITHOUT LIMITATION, WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE OR US
9、E, TITLE AND NON-INFRINGEMENT. ESDA STANDARDS AND PUBLICATIONS ARE CONSIDERED TECHNICALLY SOUND AT THE TIME THEY ARE APPROVED FOR PUBLICATION. THEY ARE NOT A SUBSTITUTE FOR A PRODUCT SELLERS OR USERS OWN JUDGEMENT WITH RESPECT TO ANY PARTICULAR PRODUCT DISCUSSED, AND ESDA DOES NOT UNDERTAKE TO GUARA
10、NTEE THE PERFORMANCE OF ANY INDIVIDUAL MANUFACTURERS PRODUCTS BY VIRTUE OF SUCH STANDARDS OR PUBLICATIONS. THUS, ESDA EXPRESSLY DISLAIMS ANY RESPONSIBILITY FOR DAMAGES ARISING FROM THE USE, APPLICATION, OR RELIANCE BY OTHERS ON THE INFORMATION CONTAINED IN THESE STANDARDS OR PUBLICATIONS. NEITHER ES
11、DA, NOR ITS MEMBERS, OFFICERS, EMPLOYEES OR OTHER REPRESENTATIVES WILL BE LIABLE FOR DAMAGES ARISING OUT OF, OR IN CONNECTION WITH, THE USE OR MISUSE OF ESDA STANDARDS OR PUBLICATIONS, EVEN IF ADVISED OF THE POSSIBILITY THEREOF. THIS IS A COMPREHENSIVE LIMITATION OF LIABILITY THAT APPLIES TO ALL DAM
12、AGES OF ANY KIND, INCLUDING WITHOUT LIMITATION, LOSS OF DATA, INCOME OR PROFIT, LOSS OF OR DAMAGE TO PROPERTY AND CLAIMS OF THIRD PARTIES. Published by: Electrostatic Discharge Association 7900 Turin Road, Bldg. 3 Rome, NY 13440 Copyright 2018 by EOS/ESD Association, Inc. All rights reserved No part
13、 of this publication may be reproduced in any form, in an electronic retrieval system or otherwise, without the prior written permission of the publisher. Printed in the United States of America ISBN: 1-58537-297-8 DISCLAIMER OF WARRANTIES DISCLAIMER OF GUARANTY LIMITATION ON ESDAs LIABILITY CAUTION
14、 NOTICE ANSI/ESD STM4.1-2017 i (This foreword is not part of ESD Association Standard Test Method ANSI/ESD STM4.1-2017) FOREWORD The purpose of an ESD protective worksurface is to aid in the prevention of damage to ESD-susceptible items. There are several ways these surfaces may act to provide this
15、protection and they are often confused in practice. One involves the removal of charge residing on the surface of a conductive/dissipative material. A second charge-removal task involves the charge on an object such as a conductive or dissipative tote box that is placed on the surface. In this case,
16、 the charge must flow across the zone between the object and the worksurface, which can interpose a considerable contact resistance. A third charge removal task involves current flow from a charged, susceptible item placed on the surface. In this case, a low discharge current is desirable. The degre
17、e of protection afforded by a worksurface is strongly related to the time needed to discharge an object. In practice, some form of resistance value is commonly given as an indication of the effectiveness of the worksurface. Strictly speaking, this description is incomplete since discharge time depen
18、ds on several other factors such as the effective capacitance of the worksurface, contact resistance and the actual discharge path. However, the capacitance does not usually vary as much as resistance. The other effects are very dependent on the individual situation. As a result, resistance seems th
19、e best single predictor of performance of ESD-protective worksurfaces. This standard test method relies on resistance measurements, utilizing standard instruments, to provide a means of evaluation of worksurface materials. Conversely, resistivity is an intrinsic material property and is not within t
20、he scope or purpose of the standard test method. This standard test method1 sets forth resistance test methods that can be used to qualify worksurfaces and to obtain relative estimates of their ability to remove electrical charge from non-insulative objects placed on the surface. A worksurface, whic
21、h is conductive enough to discharge an object, may also pose a safety hazard. The work performed on the worksurface often entails the use of tools and test instruments, which operate at voltages high enough to cause electrical shock. The presence of a worksurface tested using the methods described i
22、n this document will not guarantee personnel safety. This document was originally designated ANSI/ESD S4.1-1997 and approved on September 20, 1997. ANSI/ESD S4.1-2006 was a reaffirmation of ANSI/ESD S4.1-1997 and approved on February 26, 2006. ANSI/ESD S4.1-2006 was redesignated ESD S4.1-2006 upon a
23、dministrative withdrawal from the American National Standards Institute on July 14, 2016. ANSI/ESD STM4.1-2017 is a revision and redesignation of ESD S4.1-2006 and was approved on September 7, 2017. 1ESD Association Standard Test Method (STM): A precise statement of a set of requirements to be satis
24、fied by a material, product, system or process that also specifies the procedures for determining whether each of the requirements is satisfied. ANSI/ESD STM4.1-2017 ii At the time ANSI/ESD STM4.1-2017 was prepared, the 4.0 Worksurfaces Subcommittee had the following members: Dale Parkin, Chair Seag
25、ate Technology Nate Ashworth Julie Industries, Inc./StaticSmart Flooring Mary Kay Botkins ACL Staticide, Inc. Kevin Duncan, TAS Rep Seagate Technology David Girard Honeywell Aerospace Shane Heinle Digi-Key Corporation Chuck McClain Northwest Electrostatic Services Daniel OBrien University of Dayton
26、Research Institute Keith Peterson Missile Defense Agency Thomas Ricciardelli SelecTech/StaticStop Robert Vermillion RMV Technology Group, LLC Craig Zander Transforming Technologies The following individuals contributed to the development of ANSI/ESD S4.1-2006 and/or ANSI/ESD S4.1-1997. Brent Beamer
27、Static Control Components Larry Burich Lockheed Dave Diegan AFM Inc. Steve Gerken USAF Ron Gibson Celestica Larry Green USAF Leo G. Henry AMD Ron Johnson Intel John Kinnear IBM William Klein K&S Labs Dale Parkin IBM Ronald Schwartz Stanley Vidmar Fred Tenzer Duracoat Shane Wooldridge Kewaunee Scient
28、ific ANSI/ESD STM4.1-2017 iii TABLE OF CONTENTS 1.0 PURPOSE . 1 2.0 SCOPE 1 3.0 REFERENCED DOCUMENTS . 1 4.0 DEFINITION OF TERMS . 1 5.0 PERSONNEL SAFETY . 1 6.0 TEST EQUIPMENT . 2 6.1 RESISTANCE MEASUREMENT ELECTRODE(S) . 2 6.2 STAINLESS STEEL PLATE 2 6.3 INSULATIVE SUPPORT SURFACE 2 6.4 RESISTANCE
29、 MEASUREMENT APPARATUS . 2 6.5 SPECIMEN PREPARATION AND CONDITIONING 2 6.5.1 Cleaning . 2 6.5.2 Low Humidity Environment 2 6.5.3 Moderate Humidity Environment 3 7.0 PRODUCT QUALIFICATION OF WORKSURFACES 3 7.1 RESISTANCE-TO-GROUNDABLE POINT . 3 7.2 RESISTANCE POINT-TO-POINT 4 8.0 PRODUCT QUALIFICATIO
30、N OF SHELVING 6 8.1 RESISTANCE-TO-GROUNDABLE POINT . 6 8.2 RESISTANCE POINT-TO-POINT 9 9.0 PRODUCT QUALIFICATION OF MOBILE EQUIPMENT 10 9.1 RESISTANCE-TO-GROUNDABLE POINT 10 9.2 RESISTANCE POINT-TO-POINT 12 ANNEXES Annex A (Informative): Additional Considerations . 15 Annex B (Informative): Revision
31、 History of ANSI/ESD STM4.1-2017 16 FIGURES Figure 1: Worksurfaces - Resistance-to-Groundable Point 4 Figure 2: Worksurfaces - Resistance Point-to-Point 5-6 Figure 3: Shelving - Resistance-to-Groundable Point 8 Figure 4: Shelving - Resistance Point-to-Point . 10 Figure 5: Mobile Equipment - Resistan
32、ce-to-Groundable Point . 12 Figure 6: Mobile Equipment - Resistance Point-to-Point 14ESD Association Standard Test Method ANSI/ESD STM4.1-2017 1 ESD Association Standard Test Method for the Protection of Electrostatic Discharge Susceptible Items Worksurfaces Resistance Measurements 1.0 PURPOSE This
33、document provides test methods for evaluating and qualifying worksurfaces, including shelving and mobile equipment. 2.0 SCOPE This document establishes methods for resistance measurements of worksurfaces, shelving and mobile equipment used at workstations where protection of ESD susceptible items is
34、 required. 3.0 REFERENCED DOCUMENTS Unless otherwise specified, the following documents of the latest issue, revision, or amendment form a part of this document to the extent specified herein: ESD ADV1.0, ESD Associations Glossary of Terms2 ASTM D257, Standard Test Method for D-C Resistance or Condu
35、ctance of Insulating Materials3 4.0 DEFINITION OF TERMS The terms used in the body of this document are in accordance with the definitions found in ESD ADV1.0, ESD Associations Glossary of Terms available for complimentary download at www.esda.org. 5.0 PERSONNEL SAFETY THE PROCEDURES AND EQUIPMENT D
36、ESCRIBED IN THIS DOCUMENT MAY EXPOSE PERSONNEL TO HAZARDOUS ELECTRICAL CONDITIONS. USERS OF THIS DOCUMENT ARE RESPONSIBLE FOR SELECTING EQUIPMENT THAT COMPLIES WITH APPLICABLE LAWS, REGULATORY CODES, AND BOTH EXTERNAL AND INTERNAL POLICY. USERS ARE CAUTIONED THAT THIS DOCUMENT CANNOT REPLACE OR SUPE
37、RSEDE ANY REQUIREMENTS FOR PERSONNEL SAFETY. GROUND FAULT CIRCUIT INTERRUPTERS (GFCI) AND OTHER SAFETY PROTECTION SHOULD BE CONSIDERED WHEREVER PERSONNEL MIGHT COME INTO CONTACT WITH ELECTRICAL SOURCES. ELECTRICAL HAZARD REDUCTION PRACTICES SHALL BE EXERCISED AND PROPER GROUNDING INSTRUCTIONS FOR EQ
38、UIPMENT SHOULD BE FOLLOWED. THE RESISTANCE MEASUREMENTS OBTAINED THROUGH THE USE OF THIS TEST METHOD SHALL NOT BE USED TO DETERMINE THE RELATIVE SAFETY OF PERSONNEL EXPOSED TO HIGH AC OR DC VOLTAGES. 2 EOS/ESD Association, Inc., 7900 Turin Road, Bldg. 3, Rome, NY 13440-2069, 315-339-6937, www.esda.o
39、rg 3 American Society for Testing and Materials (ASTM), 1916 Race Street, Philadelphia, PA 19103-1187, 215-299-5400 ANSI/ESD STM4.1-2017 2 6.0 TEST EQUIPMENT 6.1 Resistance Measurement Electrode(s) Cylindrical electrode, 2.27 kg 2.5% (5 lb 2.5%) with a diameter of 63.5 mm 5% (2.5 inches 5%) having a
40、 contact of electrically conductive material with a Shore-A (IRHD) durometer hardness between 50 and 70. The resistance between two electrodes shall be less than 1.0 x 103 ohms when measured on a metallic surface. Conductive rubber electrodes are used for material evaluation and qualification. NOTE:
41、 Over time, conductive rubber materials used as the contact surface of the electrodes can warp. This could cause measurements to change. At this time there is no standardized method to verify if this has occurred but the user should be aware of this phenomenon. 6.2 Stainless Steel Plate One (1) stai
42、nless steel plate, with suggested dimensions of 127 mm x 254 mm x 1.57 mm thick (5 inches x 10 inches x 0.06 inch thick), or of sufficient thickness to support the weight of the specimen without becoming distorted. 6.3 Insulative Support Surface A planar (flat) surface, when used for specimen suppor
43、t, shall have a surface resistivity greater than 1.0 x 1013 ohms/square when measured per ASTM D257 or a surface resistance greater than 1.0 x 1012 ohms when measured per ANSI/ESD STM11.11. For test methods using 2.27 kg (5 lb 2.5%), 63.5 mm 5% (2.5 inch 5%) electrodes, an alternate method to verify
44、 the properties of the specimen support surface may be used, by measuring the resistance point-to-point of the material with the electrodes spaced at least 152 mm (6 inches) apart (edge-to-edge). A resistance point-to-point of at least one order of magnitude greater than the upper limit of the item
45、being measured is required. 6.4 Resistance Measurement Apparatus The measurement apparatus, called the meter, whether it is a single meter or a collection of instruments that are capable of the following: The meter shall have DC voltage of 10 volts ( 5%) while under load for measurements less than 1
46、.0 x 106 ohms and 100 volts ( 5%) while under load for measurements of 1.0 x 106 ohms and above. The meter shall be capable of making measurements up to 1.0 x 1010 ohms. If a process has a lower limit for worksurfaces then the meter shall be capable of making a measurement one order of magnitude bel
47、ow the lower limit. 6.5 Specimen Preparation and Conditioning 6.5.1 Cleaning The test specimens and electrodes shall be cleaned with a minimum 70% isopropyl alcohol-water solution using a clean, low-lint cloth each time. 6.5.2 Low Humidity Environment After cleaning, specimens shall be placed in a l
48、ow humidity environment of 12% RH 3% RH and 23oC 3oC. Preconditioning of the samples shall be a period of at least 48 hours. If the specimens are mounted, then preconditioning time shall be a minimum of 72 hours. The samples shall remain in this environment until all testing is completed. ANSI/ESD S
49、TM4.1-2017 3 6.5.3 Moderate Humidity Environment After cleaning, specimens shall be placed in a moderate humidity environment of 50% RH 5% RH and 23oC 3o C. Preconditioning of the samples shall be a period of at least 48 hours. If the specimens are mounted, then preconditioning time shall be a minimum of 72 hours. The samples shall remain in this environment until all testing is completed. 7.0 PRODUCT QUALIFICATION OF WORKSURFACES At least three (3) specimens shall be tested with minimum dimensions of 254 mm x 610 mm (10 inches x 24 inches).