NATIONAL ASSESSMENT DIRECTIVE FOR THE PRODUCT CERTIFICATE FOR WOODEN SCAFFOLDING BOARDS

Transcription

1 BRL 9923 dd NATIONAL ASSESSMENT DIRECTIVE FOR THE KOMO PRODUCT CERTIFICATE FOR WOODEN SCAFFOLDING BOARDS Technical area E2 Accepted by the Committee of Experts of SKH dd. 15 th September 2004 Accepted on by the Building Harmonisation Committee of the Foundation for Building Quality Issued by: Certification-body SKH Copyright reserved

2 GENERAL INFORMATION This national assessment directive has been declared binding on 3rd December 2004 by the certificationbody SKH in accordance with the Regulations for Certification and shall be used for the issuing of a KOMO Product certificate Wooden scaffolding boards as from 23rd February The Dutch version shall be consulted in cases of doubt. Publisher: Certification-body SKH P.O. Box AD Wageningen The Netherlands Telephone: Fax : mail@skh.org Website Certification-body SKH No part of this publication may be reproduced, stored in a retrieval system or transmitted, in any form or by any means, electronic, mechanical, photocopying, microfilming, recording or otherwise, and/or made public, without the prior permission in writing from SKH, nor may it be used without such permission for any other purpose than that for which it was produced.

3 Wooden scaffolding boards, dd Page 3 van 14 CONTENTS 1. Introduction Procedure for acquiring a product certificate Terms and definitions Product requirements Technical specification of different types of scaffolding boards 8 6. Additional requirements 9 7. Requirements with regard to the quality system External quality control by the certification-body Requirements for certification-body and members of staff Identification marks Titles of documents referred to Appendix 1: Specimen of KOMO product certificate 13

4 Wooden scaffolding boards, dd Page 4 van INTRODUCTION 1.1 General The requirements laid down in this assessment directive are being used by the certification bodies, authorized by the Council of Accreditation, when dealing with an application for a product certificate and, if necessary, maintenance of a KOMO -product certificate for Wooden scaffolding boards. The quality declarations are called KOMO -product certificates. Apart from the requirements laid down in this assessment directive, the certification bodies lay down additional requirements, in the sense of general procedure requirements of certification and attestation, as stated in the general certification or attestation regulations of the relevant body. 1.2 Subject The quality declaration applies to: Scaffolding board type 1: scaffolding boards of solid softwoods which have been machine strength graded. Scaffolding board type 2: scaffolding boards that have been composed of laminated veneer (LVL) of which the strength has been demonstrated. Scaffolding board type 3: scaffolding boards consisting of finger jointed laminated timber of which the strength has been demonstrated. The subject of this assessment directive does not apply to the complete scaffolding construction. 2. PROCEDURE FOR ACQUIRING A PRODUCT CERTIFICATE 2.1 Start The applicant of the product certificate indicates which thickness(es), widths, in case of scaffolding boards types 2 and 3, and in which timber species the scaffolding boards shall be supplied. The producer also supplies the necessary data on behalf of the setting up of the technical specification. The producer indicates which statements shall be included in the quality declaration and supplies the basis of these statements. 2.2 Pre-certification test The certification body examines whether the statements mentioned in the product certificate are in agreement with chapters 4 and 5. The pre-certification test shall be recorded, on the basis of which a KOMO -product certificate shall be issued, whether or not under certain conditions. 2.3 Assessment of the quality system of the applicant The certification body examines whether the quality system of the applicant of a product certificate agrees with chapter 7.

5 Wooden scaffolding boards, dd Page 5 van Issuing the product certificate The product certificate shall be issued according to the models accepted by the Building Harmonisation Committee in accordance with the general regulations of the certification body, when the pre-certification (section 2.2) and the assessment of the quality system (section 2.3) have been finished off positively. 2.5 External quality management After issuing the product certificate the certification body shall execute control as described in chapter TERMS AND DEFINITIONS Terms and definitions laid down in the following standards apply: - NEN 5461 Requirements for timber (KVH 2000). Sawn timber and round wood. General part. - NEN 5466 Requirements for timber (KVH 2000). Species European spruce, European pine end European larch. - NEN-EN 338 Structural timber. Strength classes. Softwoods and poplar. - NEN-EN 385 Finger jointed structural timber. Performance requirements and minimum production requirements. - NEN-EN 386 Glued laminated timber. Performance requirements and minimum production requirements. - NEN-EN 519 Structural timber. Grading, Requirements for machine strength grading of timber and grading machines. - NEN-EN Temporary equipment for the building site Scaffolding boards Performance requirements and general design. January NEN-EN Laminated Veneer Lumber (LVL). Specifications, definitions, draft classification and requirements. Apart from these the following terms and definitions apply: Machine strength grading Machine strength grading is a process whereby the strength and stiffness properties of the timber shall be determined by a machine in a non-destructive way. The strength class shall be expressed in a C-class in accordance with NEN-EN 338. The meaning of scaffolding boards in this assessment directive is: Rough-sawn (not planed) solid wooden boards (scaffolding board type 1) or composed of laminated veneer lumber (scaffolding board type 2) or laminated timber (scaffolding board type 3) which are being applied in a scaffolding construction as working floor or as an edge board.

6 Wooden scaffolding boards, dd Page 6 van PRODUCT REQUIREMENTS 4.1 General requirements Scaffolding boards shall comply with the minimum strength requirement as mentioned in table 4. The strength of each scaffolding board of type 1 shall be determined by machine by means of a strength grader of the type whereby the strength shall be determined by mechanical loading of that board. The determination shall be executed in accordance with NEN-EN 519. Machine strength grading by any other means as a mechanical loading can only be accepted as a test method if not the average strength of the scaffolding board is being determined, but the strength of the weakest spot. The strength of each scaffolding board of types 2 and 3 shall be included in the quality declaration. The determination of the strength shall be determined mechanically shall be tested mechanically. The strength shall agree with at least strength class C18 according to NEN-EN 338. Scaffolding boards of type 3 shall be produced in accordance with the requirements for laminated timber for load bearing constructions in exterior applications (BRL 1704). 4.2 Moisture content The moisture content of the scaffolding boards of type 1 shall not exceed 20% (m/m) per board, at the time of the mechanical grading and delivery. The moisture content of the scaffolding boards of type 2 shall not exceed 12% (m/m) per board at the time of mechanical testing. The moisture content of scaffolding boards of type 3 shall not exceed the moisture content as allowed for scaffolding boards of type Timber species The following timber species is allowed to be used for scaffolding boards: - European spruce (Picea abies (L.) Karst. The mixing of spruce in combination with Abies species is allowed for mechanically strength graded timber. Abies species (European fir) is often mixed in consignments of Middle-European spruce. 4.4 Additional requirements in respect of timber quality of scaffolding boards type 1 Mechanical strength grading Additionally to the mechanical testing of the scaffolding boards in accordance with NEN-EN 519, all boards shall be tested visually on the basis of the requirements laid down in table 1.These requirements deviate partially from the requirements laid down in table 1 of NEN-EN 519. In case the total length of the scaffolding board is not being tested, the non-tested parts shall have to be assessed on size of knots and slope of grain in accordance with table 2.

7 Wooden scaffolding boards, dd Page 7 van 14 Table 1. Additional quality requirements Borer holes not allowed Attack by insects not allowed Compression failure not allowed Reaction wood max. 1/5 of the width Checks: longitudinal checks max. length 300mm/ sum of the checks max. 1/3 x timber length ring shakes not allowed splits max. 150 mm Decay: brown to red not allowed blue to grey max. 5% of the surface white to yellow not allowed Wane/ mechanical damage max.1/6 of the thickness resp. width of the board Deviations per 2 m bow 10 mm length of timber (max.) spring 8 mm twist 8 mm over the full width cup 4 mm over the whole width Table 2. Size of knot and slope of grain Knot diameter on the wider face (max.) ¼ of the width of the board Knot diameter on the narrower face (max.) 2/3 of the thickness of the board Slope of grain (max.) 1 : 10 In case of assessment of the boards with exposed pith the compression side shall be the nonexposed heart side when doing the mechanical testing. 4.5 Dimensions and tolerances Scaffolding boards of type 1 shall be supplied in the following dimensions: 32 x 200 mm 38 x 200 mm 50 x 200 mm 4.6 Processing Size deviations allowed: Thickness wherever measured -0 and +2mm Width wherever measured -0 and + 5mm Table 3: Size tolerances (at a moisture content of 20% m/m): The dimensions of the scaffolding boards of types 2 and 3 and their deviations allowed shall be included in the quality declaration Nail plates In order to prevent end shakes and deformations in scaffolding boards of type 1 nail plates shall be fitted on both ends, both at the top and at the bottom of the scaffolding board.

8 Wooden scaffolding boards, dd Page 8 van 14 The nail plate shall comply with the following requirements: - the nail plates shall be made of continuously hot-dip zinc coated low carbon steel strips, on rings. Quality DX51D+Z275-N-A-C in accordance with NEN-EN or similar; - the material shall be free from harmful elements, coarse ingredients, cavities or similar; - the material shall be fine-grained and have a regular structure; - the surface shall be free from overlaps, splinters, grooves, checks, pores or similar; - the nail plate may not be corroded; - the fixation of the zinc-coating shall be tested in accordance with NEN-EN 10142, section 7.5.2; - the size of the nail plate shall be 35 x 175 x 0,9 mm. Tolerances in accordance with NEN-EN or similar. When using nail plates with other dimensions, it shall be demonstrated that, in order to prevent checking, at least a similar result shall be obtained; - the nail plate consists of at least four rows of staples. The position of the nail plate is at least 50 mm and max. 150 mm calculated from the outer side of the scaffolding board of type 1. In case of other systems to prevent the occurrence of end shakes and deviations these may be applied after these systems have to prove to work in practice. The requirements being laid down for the material shall at least comply with the requirements set out above. Scaffolding boards of types 2 and 3 do not need to be provided with a nail plate. 4.7 Other types of processing If the softwoods are being processed by the supplier, such as preservative treatment, the applying of constructive finger joints or laminating, these processes shall be carried out in accordance with the relevant assessment directive. These processes shall not influence the original strength of the timber negatively. An effective means to demonstrate this, is to have these processes being carried out under a KOMO -product certificate. Above-mentioned processes could also be carried out by third parties. On delivery it shall be indicated whether extra processes have taken place and whether these processes have taken place on the basis of the KOMO -product certificate for these processes. 5. TECHNICAL SPECIFICATION OF VARIOUS TYPES OF SCAFFOLDING BOARDS Scaffolding board type 1 In under-mentioned table the classification according to NEN EN of the minimum span for scaffolding class 4 and the minimum strength class according to NEN-EN 338, shall be laid down per thickness. Table 4: Maximum span per thickness for scaffolding class 4 Scaffolding class Thickness of Max. span Minimum strength class scaffolding board 4 32mm 950mm C24 38mm 1000mm C18 50mm 1600mm C18

9 Wooden scaffolding boards, dd Page 9 van 14 Remark: When calculating the maximum span, safety class 3 according to NEN 6702 (section 5.2) has been taken as starting point. In the scaffolding construction world of to-day a centre-to-centre distance of 900 mm is being used. By making use of strength-graded scaffolding boards one can choose from a centre-to-centre distance as laid down in above-mentioned table. Scaffolding boards types 2 and 3 A table shall be supplied by the manufacturer in which the max. spans of the scaffolding boards are included for the various thicknesses supplied. This table shall be based on the minimum requirements laid down in table 4. The quality declaration shall also include for which class of scaffolding the scaffolding boards can be used. 6. Additional requirements 6.1 Requirements with regard to members staff The members of staff carrying out the grading, processing or controlling shall have a proper knowledge of the requirements laid down in chapters 4 and 5 or for the applicable type of scaffolding board such as scaffolding boards types 2 and Requirements for finger jointed timber For the applying of constructive finger joints in accordance with BRL the timber shall first of all be machine strength graded. One of the conditions for obtaining a constructive joint is the use of an approved thermo-hardening adhesive suitable for the vicinity in which the timber shall be applied. The strength class of the finger jointed timber is equal to the lowest class of timber for the finger joints. 6.3 Equipment For the grading of scaffolding boards of type 1 the following equipment shall be available according to NEN-EN 519: - strength grading machine complying with the requirements laid down in NEN-EN 519; - measuring apparatus for the measurement of length, thickness and width; - a calibrated moisture meter. For scaffolding boards of type 2 a machine shall be available for the testing of the strength according to (draft) NEN-EN For scaffolding boards of type 3 the scaffolding board shall be produced and tested according to NEN-EN 385 and NEN-EN General instructions for use A scaffolding board that has been supplied under the KOMO -product certificate may only be used as scaffolding board in a scaffolding construction. The user is ultimately responsible for the maintenance of an optimal condition of the scaffolding from the moment of delivery. Apart from these general instructions for use the producer shall also set up his own instructions, that shall include at least the following: control on receipt, use on the building side, control upon return and control during storage.

10 Wooden scaffolding boards, dd Page 10 van REQUIREMENTS WITH REGARD TO THE QUALITY SYSTEM 7.1 Internal quality management of the producer In the following sections requirements have been formulated to which a quality system of the producer shall comply within the framework of a product certificate. 7.2 Responsibility The producer is responsible for the product and the internal quality control. 7.3 Reporting changes All changes in the quality system such as procedures, internal quality control schedules and method of production shall be reported in writing to the certification-body in advance. Management is responsible for the total quality policy. A management representative may be appointed by management, regardless of his other duties, for maintaining the internal quality control. 7.4 Internal quality control The producer shall have an internal quality control system; the following components shall at least be incorporated in this/a document: - control of raw materials on arrival; - workshop instructions; - control of the end product; - checks on the measuring equipment; and - complaints registration. 7.5 Calibration Measuring equipment shall be calibrated periodically. 7.6 Claims procedure The producer (the holder of the product certificate) shall have a proper claims registration. The way in which each claim is analysed and dealt with shall be recorded and which corrective measures have been taken. 8. EXTERNAL QUALITY CONTROL BY CERTIFICATION-BODY 8.1 General The external quality control by the certification-body has been laid down in the product certification regulations of this body. These shall be sent to the producers together with other relevant information. 8.2 External control The producer shall co-operate with the certification-body by providing access to the factory and to supply all relevant documents on request. 8.3 Control frequency The certification-body checks 4x a year unannounced whether the products comply with the

11 Wooden scaffolding boards, dd Page 11 van 14 technical specification and whether the internal quality control system of the producer comply with the requirements laid down in section 7. If necessary the Council of Experts can recommend that the frequency of the controls is adjusted on the basis of well-founded arguments. 9. REQUIREMENTS FOR CERTIFICATION-BODY AND MEMBERS OF STAFF 9.1 General The certification-body shall be authorized by the Council for Accreditation for the subject of this assessment directive. In case it concerns a new certification area for the certificationbody the subject shall have to be reported to the Council of Accreditation. 9.2 Certification of members staff Members of staff involved in the certification process shall be qualified demonstrable for the execution of the required activities. In respect of education / assessment / experience the following qualification requirement apply. Function Task Education Assessment/Experience certification - execution of pre- - level of Higher - training of auditor ISO 9001 certification test Vocational Education - experience in the timber industry - assessment of reporting by auditors - handling of complaints auditor - execution of external quality control after issue of certificate - Level of Intermediate Vocational Education - training in the timber industry - experience in the timber industry 10. IDENTIFICATION MARKS On each scaffolding board the following information shall be stated. Scaffolding boards types 1 and 3: logo or the words KOMO ; the product certificate number; production code; scaffolding class 4 or indication SK4; strenght class according to EN 338. Scaffolding board type 2: logo or words KOMO ; the product certificate number; production code scaffolding class 4 or indication SK4 (or higher) type and name of product.

12 Wooden scaffolding boards, dd Page 12 van TITLES OF DOCUMENTS REFERRED TO * ) NEN-EN 338: NEN-EN 385: NEN-EN 386: NEN-EN 519: NEN 5461: NEN 5466: NEN 6702: NEN 6760: 1996 Structural timber. Softwood and poplar. Strength classes Finger jointed timber. Performance requirements and minimum production Requirements 2001 Glued laminated timber. Performance requirements and minimum production requirements 1995 Structural timber. Grading. Requirements for machine strength grading of timber and grading machines Requirements for timber (KVH 2000). Sawn timber and round wood. General part Requirements for timber (KVH 2000). Species European spruce, European pine and European larch. July Including amendment A1: Technical principles for building structures. TGB Loadings and deformations Timber structures. TGB General principles. Requirements and Determination methods. NEN-EN 10142: 2000 Continuously hot-dip zinc coated low carbon steel strip and sheet for cold forming. Technical delivery conditions. NEN-EN 10143: 1993 Continuously hot-dip metal coated steel sheet and strip. Tolerances of dimensions and shape. NEN-EN Façade scaffolding manufactured from pre-fabricated components Part 1: Product specifications. NEN-EN Temporary building site equipment Part 2: Information about materials. Draft standards NEN-EN Façade scaffolding manufactured from pre-fabricated components. - Part 2: Particular method of a constructive design. NEN-EN Temporary building site equipment Scaffolding Performance requirements and general design. NEN-EN 14279: 2001 Laminated Veneer Lumber (LVL). Specifications, definitions, classification and requirements. BRL 1701 Finger jointed timber and extended sheet material. Issued by SKH *) *) For the correct date of this BRL reference is made to the Overview of quality declarations of SBK.

13 Wooden scaffolding boards, dd Page 13 van 14 KOMO product certificate Semi-manufactured product Stichting Keuringsbureau Hout SKH Visiting address: 'Het Cambium', Nieuwe Kanaal 9c, 6709 PA Wageningen P.O.Box 159, 6700 AD Wageningen, the Netherlands Telephone: +31 (0) Fax:: +31 (0) Website: Wooden scaffolding boards Producer Name Visiting address Postal code of visiting address Postal address Postal code of postal address Telephone: Fax: Website: Factory Importer Declaration of SKH This product certificate has been issued by SKH on the basis of BRL 9923, Wooden scaffolding boards, in accordance with the SKH Regulations for Certification. SKH declares that there is a legitimate confidence that the scaffolding boards manufactured by the producer continuously comply with the technical specification laid down in this product certificate, provided that is has been provided with the KOMO -mark depicted hereunder, in a way as indicated in this product certificate. SKH declares that the certified scaffolding boards when applied under above-mentioned conditions comply with the relevant requirements. For the authorization by the Minister of VROM reference is made to the Overview of authorized quality declarations in the building industry as given on the website of the Foundation for Building Quality (SBK), For SKH R. Wigboldus, director Users of this product certificate are advised to enquire at SKH whether this document is still valid. This product certificate consists of... pages. KOMO-logo is a collective mark of SBK Building Act supporting CE The following has been assessed: quality system product Periodic control

14 Wooden scaffolding boards, dd Page 14 van 14 1 PRODUCT SPECIFICATION 1.1 Subject Wooden scaffolding boards 1.2 Marking Each wooden scaffolding board shall be marked KOMO -mark The execution of this mark depends on the type of scaffolding board. For scaffolding boards types 1 and 3 as follows: - KOMO -mark - no.«certificate number» - production code - scaffolding class 4 or indication SK4 - strength class according to NEN-EN 338 For scaffolding board type 2 as follows: - KOMO -mark - no.«certificate number» - production code - scaffolding class 4 or indication SK4 - type and name of product Location of the mark: clearly visible on each scaffolding board supplied. 2. SUGGESTIONS FOR THE USER The producer shall set up his own operating instructions that shall contain at least the following subjects: control on receipt, use on the building site, control when returned and control during storage.