ﺍﻟﻌﺭﺒﻴﺔ ﺍﻟﺨﻠﻴﺞ ﻟﺩﻭل ﺍﻟﺘﻌﺎﻭﻥ ﻤﺠﻠﺱ ﻟﺩﻭل ﺍﻟﺘﻘﻴﻴﺱ  ﻫﻴﺌﺔ 
GCC STANDARDIZATION ORGANIZATION (GSO) 
 
 
 
 
 
 ﻤﺸﺭﻭﻉ : ﻨﻬﺎﺌﻲ  
 
   
GSO2/FDS/ ISO PAS 22574:2011 
ISO PAS 22574:2007 
 
 
 
 ﺍﻟﻔﺤﺹ ــ ﺍﻟﻤﻜﺎﺒﺢ ﺒﺒﻁﺎﻨﺎﺕ  ﺍﻻﺤﺘﻜﺎﻙ  ﻤﻭﺍﺩ ــ ﺍﻟﻁﺭﻕ ﻤﺭﻜﺒﺎﺕ
ﺍﻟﻅﺎﻫﺭﻱ  
 
 
Road vehicles — Brake linings frictions materials — Visual  
 
إﻋﺪاد 
 
 ﺍﻟﻤﺭﻜﺒﺎﺕ  ﻤﻭﺍﺼﻔﺎﺕ  ﻟﻘﻁﺎﻉ ﺍﻟﻔﺭﻋﻴﺔ  ﺍﻟﺨﻠﻴﺠﻴﺔ  ﺍﻟﻔﻨﻴﺔ ﻭﺍﻹﻁﺎﺭﺍﺕﺍﻟﻠﺠﻨﺔ   
   
 ﻟﺫﻟﻙ ﺒﺸﺄﻨﻬﺎ، ﻭﺍﻟﻤﻼﺤﻅﺎﺕ  ﺍﻟﺭﺃﻱ ﻹﺒﺩﺍﺀ ﺘﻭﺯﻴﻌﻬﺎ  ﺘﻡ ﺨﻠﻴﺠﻴﺔ ﻗﻴﺎﺴﻴﺔ ﻟﻤﻭﺍﺼﻔﺔ  ﻤﺸﺭﻭﻉ  ﺍﻟﻭﺜﻴﻘﺔ ﻫﺫﻩ
ﻗﻴﺎ ﻜﻤﻭﺍﺼﻔﺔ  ﺇﻟﻴﻬﺎ ﺍﻟﺭﺠﻭﻉ  ﻴﺠﻭﺯ ﻭﻻ ﻭﺍﻟﺘﺒﺩﻴل،  ﻟﻠﺘﻐﻴﻴﺭ ﻋﺭﻀﺔ ﻓﺈﻨﻬﺎ  ﻤﻥ ﺍﻋﺘﻤﺎﺩﻫﺎ  ﺒﻌﺩ ﺇﻻ ﺨﻠﻴﺠﻴﺔ ﺴﻴﺔ
ﺍﻟﺨﻠﻴﺠﻴﺔ  ﺍﻟﻬﻴﺌﺔ ﺇﺩﺍﺭﺓ ﻤﺠﻠﺱ.   ﺁﻭ ﺇﺱ ﺠﻲ/ ﺇﺱﺁﻴﺯﻭ  ﺇﻯ ﺒﻲ ٤٧٥٢٢ : ١١٠٢  ﺧﻠﻴﺠﻴﺔ  ﻗﻴﺎﺳﻴﺔ  ﻣﻮاﺻﻔﺔ
GSO STANDARD GSO/ISO  PAS 22574:2011  
 
1 ﺘﻘﺩﻴﻡ  
 ﺍﻷﺠﻬﺯﺓ  ﻋﻀﻭﻴﺘﻬﺎ  ﻓﻲ ﺘﻀﻡ ﺇﻗﻠﻴﻤﻴﺔ ﻫﻴﺌﺔ ﺍﻟﻌﺭﺒﻴﺔ ﺍﻟﺨﻠﻴﺞ ﻟﺩﻭل ﺍﻟﺘﻌﺎﻭﻥ ﻤﺠﻠﺱ ﻟﺩﻭل ﺍﻟﺘﻘﻴﻴﺱ ﻫﻴﺌﺔ
 ﺍﻟﻘﻴﺎﺴﻴﺔ ﺍﻟﻤﻭﺍﺼﻔﺎﺕ  ﺇﻋﺩﺍﺩ ﺍﻟﻬﻴﺌﺔ ﻤﻬﺎﻡ ﻭﻤﻥ ، ﺍﻟﻌﺭﺒﻴﺔ ﺍﻟﺨﻠﻴﺞ ﺩﻭل ﻓﻲ ﻭﺍﻟﻤﻘﺎﻴﻴﺱ  ﻟﻠﻤﻭﺍﺼﻔﺎﺕ  ﺍﻟﻭﻁﻨﻴﺔ
 ﺍﻟﺨﻠﻴﺠﻴﺔ  ﻤﺘﺨﺼﺼﺔ  ﻓﻨﻴﺔ ﻟﺠﺎﻥ ﺒﻭﺍﺴﻁﺔ  . 
 ﺍﻟﻔﻨﻴﺔ ﺍﻟﻠﺠﻨﺔ ﻋﻤل ﺒﺭﻨﺎﻤﺞ ﻀﻤﻥ ﺍﻟﻌﺭﺒﻴﺔ ﺍﻟﺨﻠﻴﺞ ﻟﺩﻭل ﺍﻟﺘﻌﺎﻭﻥ ﻤﺠﻠﺱ ﻟﺩﻭل ﺍﻟﺘﻘﻴﻴﺱ ﻫﻴﺌﺔ ﻗﺎﻤﺕ ﻭﻗﺩ  
 ٢ﺭﻗﻡ-١  " ﺍﻟﻤﺭﻜﺒﺎﺕ  ﻤﻭﺍﺼﻔﺎﺕ  ﻟﻘﻁﺎﻉ ﺍﻟﻔﺭﻋﻴﺔ ﺍﻟﺨﻠﻴﺠﻴﺔ  ﺍﻟﻔﻨﻴﺔ ﻭﺍﻹﻁﺎﺭﺍﺕﺍﻟﻠﺠﻨﺔ   "  ﺒﺘﺒﻨﻲ
ﺁﻴﺯﻭ  ﺭﻗﻡ ﺍﻟﺩﻭﻟﻴﺔ ﺍﻟﻘﻴﺎﺴﻴﺔ ﺍﻟﻤﻭﺍﺼﻔﺔﺇﺱ  ﺇﻯ ﺒﻲ  ٤٧٥٢٢/٧٠٠٢"  ﻤﺭﻜﺒﺎﺕ ﺍﻟﻁﺭﻕ ــ ﻤﻭﺍﺩ 
ﺍﻻﺤﺘﻜﺎﻙ ﺒﺒﻁﺎﻨﺎﺕ ﺍﻟﻤﻜﺎﺒﺢ ــ ﺍﻟﻔﺤﺹ ﺍﻟﻅﺎﻫﺭﻱ“   – ﺃﺼﺩﺭﺘﻬﺎ  ﻭﺍﻟﺘﻲ" ﻟﻠﺘﻘﻴﻴﺱ ﺍﻟﺩﻭﻟﻴﺔ ﺍﻟﻤﻨﻅﻤﺔ"  
، ﺍﻟﻌﺭﺒﻴﺔ ﺒﺎﻟﻠﻐﺔ ﺘﺭﺠﻤﺘﻬﺎ  ﺍﻟﻤﻤﻠﻜﻭﺘﻤﺕ  ﻭﻗﺎﻤﺕ ﺍﻟﻤﻭﺍﺼﻔﺔﺔ  ﻫﺫﻩ ﻤﺸﺭﻭﻉ  ﺒﺈﻋﺩﺍﺩ ﺍﻟﺴﻌﻭﺩﻴﺔ  ﺍﻟﻌﺭﺒﻴﺔ  . 
 ﺍﻟﻤﻭﺍﺼﻔﺔ  ﻫﺫﻩ ﺍﻋﺘﻤﺩﺕ  ﻭﻗﺩ  ﻋﻠﻴﻬﺎ ﻓﻨﻴﺔ ﺘﻌﺩﻴﻼﺕ  ﺃﻴﺔ ﺇﺩﺨﺎل ﺩﻭﻥ ﺨﻠﻴﺠﻴﺔ ﻗﻴﺎﺴﻴﺔ ﻜﻤﻭﺍﺼﻔﺔ  ﻓﻲ ﻭﺫﻟﻙ
 ﺭﻗﻡ ﺍﻟﻬﻴﺌﺔ ﺇﺩﺍﺭﺓ ﻤﺠﻠﺱ ﺍﺠﺘﻤﺎﻉ      )          (  ﺒﺘﺎﺭﻴﺦ         ﻋﻘﺩ ﺍﻟﺫﻱ ، /      /       ، ﻫـ
      ﺍﻟﻤﻭﺍﻓﻕ/      /       ﻡ  .
  
  
 
Foreword 
 
GCC Standardization Organization (GSO ) is a regional Organization which 
consists of the National Standards B odies of GCC member  States. One of 
GSO main functions is to issue Gulf Standards through specialized technical 
committees (TCs). 
GSO through the technical program of  committee TC No.2-1: " The Gulf 
technical Subcommittee for vehicles an d tyres standards” has adopted the 
International Standard No. : ISO PA S 22574:2007  “Road vehicles — Brake 
linings frictions materials — Visual " issued by International Organization for 
Standardization which has been translat ed into Arabic. The Draft Standard 
has been prepared by Kingdom of Saudi Arabia This standard has been approved as Gulf Standard without any technical 
modifications by GSO Board of Director s in its meeting No..../....  …….held 
on    /    /   /  H ,   /    /   G  
 
  
    
 Reference number
ISO/PAS 22574:2007(E)
© ISO 2007
  
 PUBLICLY 
AVAILABLE SPECIFICATION
 ISO/PAS
22574
First edition
2007-02-01
Road vehicles — Brake linings frictions 
materials — Visual inspection 
Véhicules routiers — Matériaux de friction des garnitures de freins — 
Inspection visuelle 
 ISO/PAS 22574:2007(E) 
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ii  © ISO 2007 – All rights reserved
  ISO/PAS 22574:2007(E) 
© ISO 2007 – All rights reserved   iiiContents Page 
Foreword....................................................................................................................... ...................................... v  
Introduc tion ................................................................................................................... .................................... vi  
1 Scope .......................................................................................................................... ........................... 1  
2 Characteristic features for friction materials................................................................................. .... 1 
2.1 Characteristic features for disc brake pads.................................................................................... ... 1 
2.1.1 Gapping (between mate rial and plate)........................................................................................... ..... 1 
2.1.2 Edge ch ipping .................................................................................................................. ..................... 2  
2.1.3 Splits ......................................................................................................................... ............................. 2  
2.1.4 Minor splits................................................................................................................... ......................... 3  
2.1.5 Plucked and inde nted spigots................................................................................................... .......... 3  
2.1.6 Poor consolidated  spigot holes ................................................................................................. ......... 4  
2.1.7 Excess adhesive on plate ....................................................................................................... ............. 4  
2.1.8 Material flash  on pl ate ........................................................................................................ .................. 5  
2.1.9 Abrasive coating............................................................................................................... .................... 5  
2.1.10  Anti-noise co ating runs........................................................................................................ ................ 6  
2.1.11  Skin crazing................................................................................................................... ........................ 6  
2.1.12  Underlayer di stribut ion ........................................................................................................ ................ 7  
2.1.13  Marking ........................................................................................................................ .......................... 7  
2.1.14  Unground material  surface ...................................................................................................... ............ 8  
2.1.15  Paint on friction ma terial surface............................................................................................. ........... 8  
2.1.16  Surface blisters ............................................................................................................... ...................... 9  
2.1.17  Surface inde ntati ons ........................................................................................................... ................. 9  
2.1.18  Grinding marks on fricti on material surface.................................................................................... 10 
2.1.19  Higher porosity area........................................................................................................... ................ 10  
2.1.20  Poorly consolidated  friction material .......................................................................................... ..... 11  
2.1.21  Surface contamination wi th foreign matter ..................................................................................... 1 1 
2.1.22  Surface contamination with similar friction material...................................................................... 12  
2.1.23  Friction surface structure ..................................................................................................... ............. 12  
2.2 Characteristic features fo r drum brake  linings................................................................................ 1 3 
2.2.1 Chipped edge s/corners.......................................................................................................... ............ 13  
2.2.2 Edge splits.................................................................................................................... ....................... 14  
2.2.3 Drill hole chipping at linin g ends ............................................................................................. ......... 14  
2.2.4 Drill hole burrs insi de the surface............................................................................................ ......... 15  
2.2.5 Drill hole burrs outsi de the surface ........................................................................................... ....... 16  
2.2.6 Cracks radiating from  the rivet hole ........................................................................................... ...... 16  
2.2.7 Paint on surface – Lining for riveting and bondi ng ........................................................................ 17  
2.2.8 Surface cracks ................................................................................................................. ................... 17  
2.2.9 Marking ........................................................................................................................ ........................ 18  
2.2.10  Moulding skin on inside radius surface – Linings for bonding and riveting................................ 18  
2.2.11  Moulding skin on outside radius surfa ce – linings for ri veting or bonding ................................. 19  
2.2.12  Surface blisters ............................................................................................................... .................... 19  
2.2.13  Surface grind marks ............................................................................................................ ............... 20  
2.2.14  Pitted surface (plucked surface) ............................................................................................... ........ 20  
2.2.15  Surface structure .............................................................................................................. .................. 21  
2.2.16  Poor conso lidation ............................................................................................................. ................ 21  
2.2.17  Inside surface indentations .................................................................................................... ........... 22  
2.2.18  Outside surface indentat ions ................................................................................................... ......... 22  
2.2.19  Concentration of self contained ingredie nts unless typical of the formulation .......................... 23  
2.2.20  High porosit y area ............................................................................................................. ................. 24  
2.2.21  Metal wire or plastic reinforcement ............................................................................................ ...... 25  
2.2.22  Foreign matter friction surface inclusion...................................................................................... ... 26 ISO/PAS 22574:2007(E) 
iv  © ISO 2007 – All rights reserved
 2.3 Characteristics features for bonded lined  shoes ............................................................................ 26  
2.3.1 Lining overhang on shoe  platform  edge .......................................................................................... 26 
2.3.2 Faulty shoes ................................................................................................................... ..................... 27  
2.3.3 Restricted le ver movement ...................................................................................................... .......... 27  
2.3.4 Stencilled in format ion ......................................................................................................... ............... 28  
2.3.5 Excess adhesive exudation over shoe platform edges .................................................................. 28  
2.3.6 Excess adhesive exudati on from lini ng ends .................................................................................. 29  
2.3.7 Excess primer.................................................................................................................. .................... 29  
2.3.8 Lining surfac e condi tion ....................................................................................................... ............. 30  
2.3.9 Gaps between linings and shoe platform......................................................................................... 32 
 ISO/PAS 22574:2007(E) 
© ISO 2007 – All rights reserved   vForeword 
ISO (the International Organization for Standardization) is a worldwide federation of national standards bodies 
(ISO member bodies). The work of preparing International Standards is normally carried out through ISO 
technical committees. Each member body interested in a subject for which a technical committee has been 
established has the right to be represented on that committee. International organizations, governmental and non-governmental, in liaison with ISO, also take part in the work. ISO collaborates closely with the International Electrotechnical Commission (IEC) on all matters of electrotechnical standardization. 
International Standards are drafted in accordance with the rules given in the ISO/IEC Directives, Part 2. The main task of technical committees is to prepare International Standards. Draft International Standards 
adopted by the technical committees are circulated to the member bodies for voting. Publication as an 
International Standard requires approval by at least 75 % of the member bodies casting a vote. 
In other circumstances, particularly when there is an urgent market requirement for such documents, a 
technical committee may decide to publish other types of normative document: 
⎯ an ISO Publicly Available Specification (ISO/PAS) represents an agreement between technical experts in 
an ISO working group and is accepted for publication if it is approved by more than 50 % of the members 
of the parent committee casting a vote; 
⎯ an ISO Technical Specification (ISO/TS) represents an agreement between the members of a technical 
committee and is accepted for publication if it is approved by 2/3 of the members of the committee casting 
a vote. 
An ISO/PAS or ISO/TS is reviewed after three years in order to decide whether it will be confirmed for a 
further three years, revised to become an International Standard, or withdrawn. If the ISO/PAS or ISO/TS is confirmed, it is reviewed again after a further three years, at which time it must either be transformed into an 
International Standard or be withdrawn. 
Attention is drawn to the possibility that some of the elements of this document may be the subject of patent 
rights. ISO shall not be held responsible for identifying any or all such patent rights. 
ISO/PAS 22574 was prepared by Technical Committee ISO/TC 22, Road vehicles , Subcommittee SC 2, 
Braking systems and equipment . ISO/PAS 22574:2007(E) 
vi  © ISO 2007 – All rights reserved
 Introduction 
This Publicly Available Specification is based on the “Catalogue of characteristic features for friction materials” 
of the “FEMFM-Federation of European Manufacturers of Friction Materials” issued the first time in 1980. The 
FEMFM is a European organization of national associations formed by companies engaged in the 
development and production of friction materials of various product forms. The description of the characteristic features and their design was reviewed in 1996 when technological processes, especially safety aspects and the demands made by the brake and automobile industry, were given careful consideration. PUBLICLY AVAILABLE SPECIFICATION ISO/PAS 22574:2007(E)
 
© ISO 2007 – All rights reserved   1Road vehicles — Brake linings frictions materials — Visual 
inspection 
1 Scope 
Friction linings are composite materials with complex structure. Due to their composition and their production 
process, visual appearance characteristics can occur which in a precisely defined design are to be regarded 
as specific to the product. This International Standard defines visual aspect for the identification and 
assessment of such product characteristics in quality assurance, as well as a basis for commercial and technical agreements. The sequence of the product characteristics represents no order of priority. The brake linings are inspected in the “as supplied” condition, meaning unused. In some characteristic features, there are differences between brake linings with an effective lining pad surface < 120 cm
2 and W 120 cm2. The 
acceptance criteria within the International Standard do not allow any characteristics which could impair the 
function and performance of brake linings  and are applied unless there are other agreements between the 
customer and the supplier. 
2 Characteristic features for friction materials 
2.1 Characteristic features for disc brake pads 
2.1.1 Gapping (between material and plate) 
The gap shown in Figure 1 is not acceptable. 
 
Figure 1 — Gapping (between material and plate) ISO/PAS 22574:2007(E) 
2  © ISO 2007 – All rights reserved
 2.1.2 Edge chipping 
In the case of a disc brake pad with a surface less than 120 cm2 a maximum of 1 % of the edge may chip. 
In the case of a disc brake pad with a surface equal or more than 120 cm2 a maximum of 0,5 % of the edge 
may chip. 
 
Figure 2 — Edge chipping 
2.1.3 Splits 
Splits having a length of more than 30 mm or more than 10 mm on corners or deeper than 1,5 mm shall not 
be accepted (see Figure 3). 
 
Figure 3 — Splits ISO/PAS 22574:2007(E) 
© ISO 2007 – All rights reserved  ROOF/ÉPREUVE  32.1.4 Minor splits 
Splits having a length of less than 30 mm or less than 10 mm on corners or with a depth les than 1,5 mm may 
be accepted (see Figure 4). 
 
Figure 4 — Minor splits 
2.1.5 Plucked and indented spigots 
The disc brake pad shown in Figure 5 is acceptable on each spigot up to 50 % of area and 0,5 mm deep. 
NOTE This definition also applies where spigots have been physically indented in the pad design. 
 
Figure 5 — Plucked and indented spigots ISO/PAS 22574:2007(E) 
4  © ISO 2007 – All rights reserved
 2.1.6 Poor consolidated spigot holes 
The disc brake pad shown in Figure 6 is acceptable if only one spigot is affected with up to 20 % of the 
volume being low density. This definition also applies where spigots have been physically indented in the pad design. 
 
Figure 6 — Poor consolidated spigot holes 
2.1.7 Excess adhesive on plate 
Excess adhesive on plate is acceptable provided the fitment of the part is not affected. (See Figure 5.) 
 
Figure 7 — Excess adhesive on the plate ISO/PAS 22574:2007(E) 
© ISO 2007 – All rights reserved  ROOF/ÉPREUVE  52.1.8 Material flash on plate 
A material flash on plate is acceptable up to 1mm thick outside functional zones. Flash shall be secured to 
back plate. (See Figure 8.) 
 
Figure 8 — Material flash on plate 
2.1.9 Abrasive coating 
The disc brake pad is acceptable if at least 90 % of the surface is coated. (See Figure 9.) 
 
Figure 9 — Abrasive coating ISO/PAS 22574:2007(E) 
6  © ISO 2007 – All rights reserved
 2.1.10 Anti-noise coating runs 
The anti-noise coating runs is acceptable provided fitment of part is not affected. (See Figure 10.) 
 
Figure 10 — Anti-noise coating runs 
2.1.11 Skin crazing 
Skin crazing as shown in Figure 11 is acceptable. 
 
Figure 11 — Skin crazing ISO/PAS 22574:2007(E) 
© ISO 2007 – All rights reserved  ROOF/ÉPREUVE  72.1.12 Underlayer distribution 
Presence of underlayer is acceptable on pad surface up to 2 % of area, if the distribution is according to the 
specification. (See Figure 12.) 
 
Figure 12 — Under-layer distribution 
2.1.13 Marking 
The marking shall be clear and legible. 
 
Figure 13 — Marking ISO/PAS 22574:2007(E) 
8  © ISO 2007 – All rights reserved
 2.1.14 Unground material surface 
An unground material surface equal or less than 10 % of the area is acceptable provided flatness and 
parallelism tolerances are not exceeded. (See Figure 14.) 
 
Figure 14 — Unground material surface 
2.1.15 Paint on friction material surface 
Paint on friction material surface is acceptable up to 10 % of the surface area. (See Figure 15.) 
 
Figure 15 — Paint on friction material surface ISO/PAS 22574:2007(E) 
© ISO 2007 – All rights reserved  ROOF/ÉPREUVE  92.1.16 Surface blisters 
Surface blisters are acceptable if no surface lift is detectable. (See Figure 16.) 
 
Figure 16 — Surface blisters 
2.1.17 Surface indentations 
Surface indentations are acceptable up to 2 % of the surface in total, but a single indentation shall not exceed 
1 % of the material surface; (See Figure 17.) 
 
Figure 17 — Surface indentations ISO/PAS 22574:2007(E) 
10  © ISO 2007 – All rights reserved
 2.1.18 Grinding marks on friction material surface 
Grinding marks on friction material surface are acceptable. (See Figure 18.) 
 
Figure 18 — Grinding marks on friction material surface 
2.1.19 Higher porosity area 
In the case of an effective material surface of less than 120 cm2 a maximum of 5 % surface area with a higher 
porosity is acceptable, provided the material contours are not affected. 
The percentage of allowable higher porosity shall be equal or less than 2 % in the case of an effective material 
surface equal or more than 120 cm2. (See Figure 19.) 
 
Figure 19 — Higher porosity area ISO/PAS 22574:2007(E) 
© ISO 2007 – All rights reserved  ROOF/ÉPREUVE  112.1.20 Poorly consolidated friction material 
In the case of an effective material surface of less than 120 cm2 a maximum of 1 % surface area with poorly 
consolidated friction material is acceptable. 
The percentage of poor consolidation shall be equal or less than 0,5 % in the case of an effective lining 
surface equal or more than 120 cm2. (See Figure 20.) 
 
Figure 20 — Poorly consolidated friction material 
2.1.21 Surface contamination with foreign matter 
Such a contamination is not acceptable. (See Figure 21.) 
 
Figure 21 — Surface contamination foreign matter ISO/PAS 22574:2007(E) 
12  © ISO 2007 – All rights reserved
 2.1.22 Surface contamination with similar friction material 
Spots on friction material with a surface equal or less than 1 % of the total surface are acceptable. 
Spots on friction material with a surface equal or less than 2 % of the total surface are acceptable, only if the 
friction properties are not affected. 
2.1.23 Friction surface structure 
In the case of an effective material surface of less than 120 cm2 the concentration of self contained 
ingredients is acceptable up to 5 % of the surface area but not continuous. 
In the case of an effective material surface equal or more than 120 cm2 the concentration of self contained 
ingredients is acceptable up to 3 % of the surface area but not continuous. (See Figure 22.) 
Non homogenous appearance is accepted for special qualities including surface plucking. (See Figure 23.) 
 
Figure 22 — Friction surface structure 
 
Figure 23 ISO/PAS 22574:2007(E) 
© ISO 2007 – All rights reserved  ROOF/ÉPREUVE  132.2 Characteristic features for drum brake linings 
2.2.1 Chipped edges/corners 
In the case of a lining surface of less than 120 cm2 chipped edges/corners are acceptable up to 10 mm2 and 
half the lining thickness. No more than 2 are allowed per lining. (See Figure 24.) 
In the case of a lining surface equal or more than 120 mm2 chipped edges/ corners are acceptable up to 
20 mm2 and half the lining thickness. No more than 2 are allowed per lining. (See Figure 25.) 
 
Figure 24 — Chipped edges/corners on linings < 120 mm2 
 
Figure 25 — Chipped edges/ corners W 120 mm2 ISO/PAS 22574:2007(E) 
14  © ISO 2007 – All rights reserved
 2.2.2 Edge splits 
Edge splits are not acceptable. (See Figure 26.) 
 
Figure 26 — Edge splits 
2.2.3 Drill hole chipping at lining ends 
The lining shown in Figure 27 is not acceptable. The lining shown in Figure 28 is acceptable if one hole only is concerned. 
 
Figure 27 — Drill hole chipping at lining ends ISO/PAS 22574:2007(E) 
© ISO 2007 – All rights reserved  ROOF/ÉPREUVE  15
 
Figure 28 — Drill hole chipping at lining ends 
2.2.4 Drill hole burrs inside the surface 
Drill hole burrs on the inside the surface are not acceptable. (See Figure 29.) 
 
Figure 29 — Drill hole burrs inside the surface ISO/PAS 22574:2007(E) 
16  © ISO 2007 – All rights reserved
 2.2.5 Drill hole burrs outside the surface 
Drill hole burrs outside the surface are acceptable up to a height of 1 mm. (See Figure 30.) 
 
Figure 30 — Drill hole burrs outside the surface 
2.2.6 Cracks radiating from the rivet hole 
Cracks radiating from the rivet hole are not acceptable. (See Figure 31.) 
 
Figure 31 — Cracks radiating from the rivet hole ISO/PAS 22574:2007(E) 
© ISO 2007 – All rights reserved  ROOF/ÉPREUVE  172.2.7 Paint on surface – Lining for riveting and bonding 
Paint on surface is acceptable up to 5 % of the area on both inside and outside surfaces, paint runs are not 
acceptable. (See Figure 32.) 
 
Figure 32 — Paint on surface 
2.2.8 Surface cracks 
Cracks are acceptabl e up to 25 % of the lining width but not longer than 30 mm, up to 0,2 mm deep. They are 
not acceptable across full lining width independent of depth. (See Figure 33.) 
 
Figure 33 — Surface cracks ISO/PAS 22574:2007(E) 
18  © ISO 2007 – All rights reserved
 2.2.9 Marking 
Marking shall be legible. (See Figure 34.) 
 
Figure 34 — Marking 
2.2.10 Moulding skin on inside radius surface – Linings for bonding and riveting 
Where inside ground finish is specified for linings for bonding, up to 3 % of surface are acceptable provided 
the unground area is not at the lining ends and dimensional specifications are maintained. 
Where inside ground finish is specified for linings for riveting, up to 10 % of surface are acceptable provided 
the unground area is not at the lining ends and dimensional specifications are maintained. (See Figure 35.) 
 
Figure 35 — Moulding skin on inside radius surface ISO/PAS 22574:2007(E) 
© ISO 2007 – All rights reserved  ROOF/ÉPREUVE  192.2.11 Moulding skin on outside radius surface – linings for riveting or bonding 
Moulded skin is acceptable up to 3 % of surface area provided dimensional specifications are maintained. 
(See Figure 36.) 
 
Figure 36 — Moulding skin on outside radius surface 
2.2.12 Surface blisters 
Surface blisters are not acceptable (See Figure 37.) 
 
Figure 37 — Surface blisters ISO/PAS 22574:2007(E) 
20  © ISO 2007 – All rights reserved
 2.2.13 Surface grind marks 
Surface grind marks are acceptable as long as dimensional specifications are maintained. (See Figure 38.) 
 
Figure 38 — Surface grind marks 
2.2.14 Pitted surface (plucked surface) 
Pitted surface which is typical of certain materials is acceptable (See Figure 39.) 
 
Figure 39 — Pitted surface ISO/PAS 22574:2007(E) 
© ISO 2007 – All rights reserved  ROOF/ÉPREUVE  212.2.15 Surface structure 
In case of surface contamination by self contained ingredients (poor distribution) i.e. unopened fibres the lining 
is acceptable if the contamination equals or is less than 2 % of the friction side area and if the contamination equals or is less than 4 % of the non friction side area. (See Figure 40.) 
 
Figure 40 — Surface structure 
2.2.16 Poor consolidation 
The poor consolidation as shown in Figure 41 is not acceptable. 
 
Figure 41 — Poor consolidation ISO/PAS 22574:2007(E) 
22  © ISO 2007 – All rights reserved
 2.2.17 Inside surface indentations 
In the case of an effective lining surface of less than 120 cm2 inside surface indentations are acceptable up to 
30 mm2 and 1 mm deep. No more than 2 is allowed and each shall be more than 5 mm from a drill hole. 
In the case of an effective lining surface equal or more than 120 cm2 inside surface indentations are 
acceptable up to 30 mm2 and 1 mm deep. No more than 2 are allowed and each shall be more than 10 mm 
from a drill hole. (See Figure 42.) 
 
Figure 42 — Inside surface indentations 
2.2.18 Outside surface indentations 
2.2.18.1 Linings W 120 cm2 
Outside surface indentations are acceptable up to 30 mm2 and 1 mm deep. No more than 2 are allowed. 
(See Figure 43.) 
 
Figure 43 — Outside surface indentations – linings W 120 cm2 ISO/PAS 22574:2007(E) 
© ISO 2007 – All rights reserved  ROOF/ÉPREUVE  232.2.18.2 Linings < 120 cm2 
Outside surface indentations are acceptable up to 20 mm2 and 1 mm deep. No more than 2 are allowed. 
(See Figure 44.) 
 
Figure 44 — Outside surface indentations - lining < 120 cm2 
2.2.19 Concentration of self contained ingredients unless typical of the formulation 
In the outside radius a maximum of 1 % of the surface is acceptable, but each concentration area to be a 
maximum area of 25 mm2. (See Figure 45.) 
 
Figure 45 — Concentration of self contained ingredients (Outside radius) ISO/PAS 22574:2007(E) 
24  © ISO 2007 – All rights reserved
 In the inside radius a maximum of 2 % of the surface is acceptable, each to be a maximum area of 50 mm2. 
(See Figure 46.) 
 
Figure 46 — Concentration of self contained ingredients (Inside radius) 
2.2.20 High porosity area 
A high porosity area is acceptable provided the overall density of linings is specified and the profile is not 
affected. (See Figure 47.) 
 
Figure 47 — High porosity area ISO/PAS 22574:2007(E) 
© ISO 2007 – All rights reserved  ROOF/ÉPREUVE  252.2.21 Metal wire or plastic reinforcement 
2.2.21.1 Showing on the inside surface 
This is acceptable. (See Figure 48.) 
 
Figure 48 — Inside surface 
2.2.21.2 Showing in rivet hole 
Plastic reinforcement is acceptable. Metal reinforcement is not acceptable. (See Figure 49.) 
 
Figure 49 — Rivet hole ISO/PAS 22574:2007(E) 
26  © ISO 2007 – All rights reserved
 2.2.22 Foreign matter friction surface inclusion 
Foreign matter friction surface inclusion is not acceptable, but for inclusions of similar friction material it may 
be accepted as follows (see Figure 50): 
⎯ in the case of a lining surface of less than 120 cm2 an inclusion of a surface of a maximum of 
25 mm2 is acceptable; 
⎯ in the case of a lining surface of 120 cm2 or more an inclusion of a surface of a maximum of 50 mm2 
is acceptable. 
 
Figure 50 — Inclusions 
2.3 Characteristics features for bonded lined shoes 
2.3.1 Lining overhang on shoe platform edge 
A lining overhang on shoe platform edge is acceptable up to a maximum of 1 mm over whole lining length on 
one edge only (unless otherwise stated in the specification). (See Figure 51.) 
 
Figure 51 — Lining overhang on shoe platform edge ISO/PAS 22574:2007(E) 
© ISO 2007 – All rights reserved  ROOF/ÉPREUVE  272.3.2 Faulty shoes 
Faulty shoes damaged in bonding process are not acceptable unless of a minor nature not affecting fitment. 
(See Figure 52.) 
 
Figure 52 — Faulty shoes 
2.3.3 Restricted lever movement 
A restricted lever movement is not acceptable. It shall not be restricted by excess primer or incorrect riveting. 
(See Figure 53.) 
 
Figure 53 — Restricted lever movement ISO/PAS 22574:2007(E) 
28  © ISO 2007 – All rights reserved
 2.3.4 Stencilled information 
Lining edge and shoe web marking shall be clear. (See Figure 54.) 
 
Figure 54 — Stencilled information 
2.3.5 Excess adhesive exudation over shoe platform edges 
A excess of adhesive exudation is acceptable up to 1,5 mm overhang on either edge of shoe platform. 
(See Figure 55.) 
 
Figure 55 — Excess adhesive exudation – shoe platform edges ISO/PAS 22574:2007(E) 
© ISO 2007 – All rights reserved  ROOF/ÉPREUVE  292.3.6 Excess adhesive exudation from lining ends 
An excess adhesive exudation from lining ends is acceptable. (See Figure 56.) 
 
Figure 56 — Excess adhesive exudation – lining ends 
2.3.7 Excess primer 
The excess primer, e.g. in web location holes and abutment areas is acceptable provided the fitment and the 
performances are not affected. (See Figure 57.) 
 
Figure 57 — Excess primer ISO/PAS 22574:2007(E) 
30  © ISO 2007 – All rights reserved
 2.3.8 Lining surface condition 
2.3.8.1 Rigid material ground on the shoe — Unground areas 
An unground area is acceptable if it is 10 % or less of the lining surface area with a depth of 0,2 mm or less. 
(See Figure 58.) 
 
Figure 58 — Lining surface condition 
2.3.8.2 Rigid material ground on the shoe – Grinding marks 
Grinding marks are acceptable if they are 20 % or less of the lining surface area with a depth of 0,2 mm or 
less. (See Figure 59.) 
 
Figure 59 — Lining surface condition ISO/PAS 22574:2007(E) 
© ISO 2007 – All rights reserved  ROOF/ÉPREUVE  312.3.8.3 Flexible material 
Bonding band impression causing lip of material on lining edge is not acceptable. (See Figure 60.) 
Bonding band impression causing reduction in material thickness is acceptable at lining ends over 5 % 
surface area, provided conditions of lining overhang are met. (See Figure 61.) 
 
Figure 60 — Flexible material (1) 
 
Figure 61 — Flexible material (2) ISO/PAS 22574:2007(E) 
32  © ISO 2007 – All rights reserved
 2.3.9 Gaps between linings and shoe platform 
2.3.9.1 Lining edges 
A gap is acceptable if it is equal or less than 0,15 mm wide, equal or less than 5,0 mm deep and up to a 
maximum of 25 % of one side length. (See Figure 62.) 
 
Figure 62 — Gap in lining edges 
2.3.9.2 Lining ends (end lifts) 
A gap between lining and shoe platform lining ends (end lift) is not acceptable. (See Figure 63.) 
 
Figure 63 — Gap in lining ends ISO/PAS 22574:2007(E) 
ICS  43.040.40 
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© ISO 2007 – All rights reserved