1、 Collection of SANS standards in electronic format (PDF) 1. Copyright This standard is available to staff members of companies that have subscribed to the complete collection of SANS standards in accordance with a formal copyright agreement. This document may reside on a CENTRAL FILE SERVER or INTRA
2、NET SYSTEM only. Unless specific permission has been granted, this document MAY NOT be sent or given to staff members from other companies or organizations. Doing so would constitute a VIOLATION of SABS copyright rules. 2. Indemnity The South African Bureau of Standards accepts no liability for any
3、damage whatsoever than may result from the use of this material or the information contain therein, irrespective of the cause and quantum thereof. ISBN 978-0-626-21746-4 SANS 99:2008Edition 3 SOUTH AFRICAN NATIONAL STANDARD White chalks Published by SABS Standards Division 1 Dr Lategan Road Groenklo
4、of Private Bag x191 Pretoria 0001 Tel: +27 12 428 7911 fax: +27 12 344 1568 www.sabs.co.za SABS SANS 99:2008 Edition 3 Table of changes Change No. Date Scope Foreword This South African standard was approved by National Committee SABS TC 1007, Stationery and office requisites, in accordance with pro
5、cedures of SABS Standards Division, in compliance with annex 3 of the WTO/TBT agreement. This document was published in September 2008. This document supersedes SABS 99:1976 (first revision). Annex A forms an integral part of this document. SANS 99:2008 Edition 3 1 Contents Page Foreword 1 Scope 3 2
6、 Normative references 3 3 Definitions . 3 4 Requirements 3 5 Sampling and compliance with the standard 5 6 Inspection and methods of test 6 6.1 Inspection 6 6.2 Dimensions . 6 6.3 Writing qualities and freedom from grit . 6 6.4 Transverse breaking strength . 7 6.5 Resistance to abrasion. 7 7 Packing
7、 and marking . 7 Annex A (normative) Notes to purchasers 8 SANS 99:2008 Edition 3 2 This page is intentionally left blank SANS 99:2008 Edition 3 3 White chalks 1 Scope This standard specifies the requirements for soft, hard and soft dust-free white chalks. 2 Normative references The following refere
8、nced documents are indispensable for the application of this document. For dated references, only the edition cited applies. For undated references, the latest edition of the referenced document (including any amendments) applies. Information on currently valid national and international standards c
9、an be obtained from SABS Standards Division. CKS 36, Chalk writing boards for schools. SANS 223, Writing equipment Coloured chalks and pastels. 3 Definitions For the purposes of this document, the following definitions apply. 3.1 acceptable acceptable to the authority administering this standard or
10、to the parties concluding the purchase contract, as relevant 3.2 lot not less than 100 and not more than 1 000 000 chalks of the same type in containers bearing the same batch identification, from one manufacturer, submitted at any one time for inspection and testing 4 Requirements 4.1 Soft type cha
11、lks 4.1.1 Colour The colour of the chalk shall be white. 4.1.2 Shape The chalks shall have a circular cross-section and shall be uniformly tapered. SANS 99:2008 Edition 3 4 4.1.3 Dimensions When measured in accordance with 6.2, the length of a soft chalk shall be 81,0 mm 2,0 mm and the diameters at
12、the base and at the tip shall be 11,0 mm 1,0 mm and 9,5 mm 1,0 mm respectively. 4.1.4 Finish The finish shall be smooth and at least 75 % of the chalks shall be free from external blowholes. 4.1.5 Writing qualities and freedom from grit When tested in accordance with 6.3, the chalks shall show no ev
13、idence of containing grit, flint, or sandy particles and shall be capable of making continuous uniform marks on a chalkboard that complies with the requirements of CKS 36. The marks shall be easily erased, and the chalks shall not scratch or otherwise harm the chalkboard. 4.1.6 Transverse breaking s
14、trength When tested in accordance with 6.4, at least 80 % of the chalks shall support, without breaking, a transverse mass-load of at least 1 200 kg. 4.1.7 Resistance to abrasion When tested in accordance with 6.5, the average loss in volume of the chalks shall be not less than 0,13 cm3and not more
15、than 0,26 cm3. 4.2 Hard type chalks 4.2.1 Colour The requirements of 4.1.1 shall apply. 4.2.2 Shape The chalks shall be cylindrical. 4.2.3 Dimensions When measured in accordance with 6.2, the length of a chalk shall be 76,0 mm 2,0 mm and the diameter 9,5 mm 1,0 mm. 4.2.4 Finish The finish shall be s
16、mooth and at least 90 % of the chalks shall be free from external blowholes. 4.2.5 Writing qualities and freedom from grit The requirements of 4.1.5 shall apply. 4.2.6 Transverse breaking strength When tested in accordance with 6.4, at least 80 % of the chalks shall support, without breaking, a tran
17、sverse mass-load of at least 1 800 kg. SANS 99:2008 Edition 3 5 4.2.7 Resistance to abrasion When tested in accordance with 6.5, the average loss in volume of the chalks shall be not less than 0,10 cm3and not more than 0,16 cm3. 4.3 Soft dust-free type chalks 4.3.1 Colour The requirements of 4.1.1 s
18、hall apply. 4.3.2 Shape The requirements of 4.2.2 shall apply. 4.3.3 Dimensions When measured in accordance with 6.2, the length of a chalk shall be 78,0 mm 2,0 mm and the diameter 9,5 mm 1,0 mm. 4.3.4 Finish The requirements of 4.2.4 shall apply. 4.3.5 Writing qualities and freedom from grit The re
19、quirements of 4.1.5 shall apply. 4.3.6 Transverse breaking strength The requirements of 4.1.6 shall apply. 4.3.7 Resistance to abrasion When tested in accordance with 6.5, the average loss in volume of the chalks shall be not less than 0,08 cm3and not more than 0,16 cm3. 5 Sampling and compliance wi
20、th the standard5.1 Sampling 5.1.1 General When no information concerning the implementation of quality control or testing during manufacture is available, the following sampling procedure shall be applied to determine whether a lot submitted for inspection and testing complies with the requirements
21、of the standard. The samples so taken shall be deemed to represent the lot for the respective properties. The sampling procedure shall also be used for adjudication in cases of dispute. 5.1.2 Sample for inspection After checking the lot for compliance with clause 4, take at random the number of chal
22、ks shown in column 2 of table 1 relative to the appropriate lot size shown in column 1, taking not more than six chalks from a container. SANS 99:2008 Edition 3 6 5.1.3 Samples for testing After inspection (see 6.1) of the sample taken in accordance with 5.1.2, take from it, as follows, the chalks f
23、or testing: a) take at random the appropriate number of chalks given in column 3 of table 1; and b) take the remainder of the chalks (see column 4 of table 1). Table 1 Sampling requirements for chalks 1 2 3 4 Samples for testing, number of chalks Lot size, number of chalks Samples for inspection, nu
24、mber of chalks Resistance to abrasion All other tests 100 2 500 24 4 20 2 501 10 000 36 6 30 10 001 25 000 48 8 40 25 001 40 000 60 10 50 40 001 100 000 72 12 60 1000 001 250 000 84 14 70 250 001 500 000 120 20 100 500 001 1 000 000 180 30 150 5.2 Compliance with the standard The lot shall be deemed
25、 to comply with the requirements of the standard if, after inspection and testing, the samples taken in accordance with 5.1 are found to comply with all the relevant requirements of the standard. 6 Inspection and methods of test 6.1 Inspection Inspect the sample taken in accordance with 5.1.2 for co
26、mpliance with the requirements for colour, shape and finish. 6.2 Dimensions Using calipers, measure the dimensions of each chalk in the sample taken in accordance with 5.1.3(b). 6.3 Writing qualities and freedom from grit 6.3.1 Carry out writing tests with each chalk in the sample taken in accordanc
27、e with 5.1.3(b), using a chalkboard that complies with the requirements of CKS 36. 6.3.2 Assess the writing qualities, and freedom from grit, flint, and sandy particles, and compliance with the other requirements of 4.1.5 or 4.2.5, as relevant. SANS 99:2008 Edition 3 7 6.4 Transverse breaking streng
28、th Use the relevant method given in SANS 223 to test each chalk in the sample taken in accordance with 5.1.3(b). 6.5 Resistance to abrasion Use the relevant method given in SANS 223 to test each chalk in the sample taken in accordance with 5.1.3(a). 7 Packing and marking 7.1 Packing 7.1.1 Containers
29、 The chalks shall be packed in acceptable containers that will withstand normal handling and transportation and that will prevent breakage of the contents. Each container shall contain only one type of chalk. 7.1.2 Number of chalks per container Unless otherwise specified by the purchaser, chalks sh
30、all be packed in quantities of 100 chalks per container. 7.2 Marking The following information shall appear in legible and indelible marking on the outside of each container or on a label securely attached to the container: a) the manufacturers name or trade mark or both; b) the words “white chalk“,
31、 the type of chalk, and the quantity of chalks; c) the batch identification. SANS 99:2008 Edition 3 8 Annex A (normative) Notes to purchasers The following requirements shall be specified in tender invitations and in each order or contract: a) The type of chalk required, i.e. soft or hard or soft dust-free (see 4.1, 4.2 and 4.3). b) The number of chalks per container if other than 100 (see 7.1.2). SABS
