《08-30166177-DC.pdf》由会员分享,可在线阅读,更多相关《08-30166177-DC.pdf(7页珍藏版)》请在三一文库上搜索。
1、a Date: 30 January 2008 Origin: National Latest date for receipt of comments: 31 MARCH 2008 Project no.: 2007/01260 Responsible committee: GSE/30 Gas installations (1st, 2nd and 3rd family gases) Interested committees: Title: Draft BS BS 6891 AMD 2 Installation of low pressure gas pipework of up to
2、35 mm (R1) in domes tic premises (2nd family gas) - Specification Supersession information: If you are aware of a current national standard which may be affected, please notify the secretary (contact details below). WARNING: THIS IS A DRAFT AND MUST NOT BE REGARDED OR USED AS A BRITISH STANDARD. THI
3、S DRAFT IS NOT CURRENT BEYOND 31 MARCH 2008. This draft is issued to allow comments from interested parties; all comments will be given consideration prior to publication. No acknowledgement will normally be sent. See overleaf for information on commenting. No copying is allowed, in any form, withou
4、t prior written permission from BSI except as permitted under the Copyright, Designs and Patent Act 1988 or for circulation within a nominating organization for briefing purposes. Electronic circulation is limited to dissemination by e-mail within such an organization by committee members. Further c
5、opies of this draft may be purchased from BSI Customer Services, Tel: +44(0) 20 8996 9001 or email . British, International and foreign standards are also available from BSI Customer Services. Information on the co-operating organizations represented on the committees referenced above may be obtaine
6、d from the responsible committee secretary. Cross-references The British Standards which implement International or European publications referred to in this draft may be found via the British Standards Online Service on the BSI web site http:/. Direct tel: 020 8996 7123 Responsible Committee Secret
7、ary: Mr B D J Williams (BSI) E-mail: Draft for Public Comment Head Office 389 Chiswick High Road London W4 4AL Telephone: +44(0)20 8996 9000 Fax: +44(0)20 8996 7001 Form 36 Version 7.0 DPC: 08/30166177 DC Licensed Copy: London South Bank University, London South Bank University, Fri Feb 15 07:19:27
8、 GMT+00:00 2008, Uncontrolled Copy, (c) BSI b Introduction Your comments on this draft are welcome and will assist in the preparation of the consequent British Standard. If no comments are received to the contrary, this draft may be implemented unchanged as a British Standard. Submission The guidanc
9、e given below is intended to ensure that all comments receive efficient and appropriate attention by the responsible BSI committee. Annotated drafts are not acceptable and will be rejected. All comments must be submitted, preferably electronically, to the Responsible Committee Secretary at the addre
10、ss given on the front cover. Comments should be compatible with Version 2003 of Microsoft Word for Windows, if possible. Any comments not submitted electronically should still adhere to these format requirements. All comments submitted should be presented as given in the example below. Further infor
11、mation on submitting comments and how to obtain a blank electronic version of a comment form are available from the BSI web site at: http:/ Template for comments and secretariat observations Date: xx/xx/200x Document: ISO/DIS xxxxx 1 2 (3) 4 5 (6) (7) MB Clause No./ Subclause No./ Annex (e.g. 3.1) P
12、aragraph/ Figure/Table/ Note (e.g. Table 1) Type of com- ment Comment (justification for change) by the MB Proposed change by the MB Secretariat observations on each comment submitted 3.1 Definition 1 ed Definition is ambiguous and needs clarifying. Amend to read . so that the mains connector to whi
13、ch no connection . 6.4 Paragraph 2 te The use of the UV photometer as an alternative cannot be supported as serious problems have been encountered in its use in the UK. Delete reference to UV photometer. Microsoft and MS-DOS are registered trademarks, and Windows is a trademark of Microsoft Corporat
14、ion. Licensed Copy: London South Bank University, London South Bank University, Fri Feb 15 07:19:27 GMT+00:00 2008, Uncontrolled Copy, (c) BSI BS 6891:2005 AMD 2 BS 6891:2005 Amendment No. 2 Foreward Delete Paragraph 4 and replace with: Amendment No 2 clarifies the situation when installing gas pipe
15、work in intermediate floors. (See 8.7.) New 3.3.1a intermediate joisted floor floor that separates one living space from another living space in the same dwelling NOTE This is not a compartment floor that separates one dwelling from another part of the building. Table 1 Add superscript A) to Column
16、3 heading: Add following note A) to bottom of table: A) Flow details for corrugated stainless steel conforming to BS 7838 are given in the above Table. For flow details of corrugated stainless steel conforming to BS EN 15266, the manufacturer should be contacted. BS 7838 is due to be withdrawn in Fe
17、bruary 2009. 6.2, Para 3 Insert “or BS EN 15266“ after “BS 7838“. 8.7 Where installation pipes are laid in intermediate joisted floors in dwellings, unless there is sufficient adventitious ventilation available, ventilation shall be provided in accordance with Table 3. NOTE Additional guidance on in
18、stallation pipework in: flats and other multi-dwelling buildings is given in 8.1 of the Institution of Gas Engineers and Managers publication IGE/G/5 2006 12; timber framed and light steel framed buildings is given in 6.2 of the Institution of Gas Engineers and Managers publication IGE/UP/7 Edition
19、2, 2006 7. COMMENTARY AND RECOMMENDATIONS ON 8.7 Research undertaken by Advantica 13 on behalf of the Gas Industry Safety Group (GISG) has proved that where gas installation pipework is installed in intermediate joisted floors in dwellings, there is sufficient adventitious ventilation of the floor c
20、onstruction to safely disperse any minor leakage of gas. Therefore, there is no requirement to install purpose provided ventilation to floors of this construction in conventional masonry, timber frame or light steel frame buildings. A summary of the research project and its principal conclusions can
21、 be found in Annex B. The results and conclusions of this Report apply to Natural gas installations only and, therefore, should not be applied to installations supplied with LPG/Air gas mixtures. Licensed Copy: London South Bank University, London South Bank University, Fri Feb 15 07:19:27 GMT+00:00
22、 2008, Uncontrolled Copy, (c) BSI BS 6891:2005 AMD 2 New Annex Insert new Annex B: Annex B (informative) Summary and principal conclusions of the Advantica Research Project “Gas in intermediate floors“, Report Number 6699. NOTE The results and conclusions of this Report apply to Natural gas installa
23、tions only and, therefore, should not be applied to installations supplied with LPG/Air gas mixtures. B.1 Introduction Regulation 19(6) of the Gas Safety (Installation and Use) Regulations 1 requires adequate ventilation to be present when gas installation pipework is located within voids, shafts an
24、d ducts. With the general use of board materials (chipboard, oriented strand board, plywood) as the decking there was concern regarding the level of potential gas build-up within the voids between joists of intermediate floors associated with minor gas leaks. B.2 Rationale for specification of a min
25、or leak In developing the specification for this research, it was determined that a minor gas leak is an escape equal to or less than 19 ml/min under the conditions specified in IGE/UP/1B 14 based upon the following information: a) Regulation 19(6) of the GS(I the smallest leak that can be detected
26、by smell is 1 ml/min; the smallest leak that can be ignited is 14 ml/min. Hence it has been determined that a minor gas escape is an escape equal to or less than 19 ml/min under the conditions specified in IGE/UP/1B 14. B.3 Test conditions Whilst recognizing that there is a wide range of possible te
27、st floor layouts and gas leak rates, a project specification was developed to provide data on gas build-up arising from a minor gas leak in a: a) typical new build floor; b) a floor covered to represent a more sealed arrangement; and c) a floor, including a skirting arrangement and stud walling. Adv
28、antica undertook an experimental study 13, commissioned by the Gas Industry Safety Group (GISG) to make gas concentration measurements within, above and below this representative three-metre square floor cassette with typical openings for plumbing and electrical services. The tests were performed us
29、ing a fixed orifice opening and a range of gas supply pressures to vary the gas leak rate. B.4 Conclusions The experimental study concluded that: a) In the event of a gas leak from pipes in the floor void, a modern floor construction allows passage of gas across joists and the voids created by them
30、as a consequence of the installation of electrical and plumbing services. b) The profiles for gas build-up and decay within the floor compartments and the upper and lower volumes (constructed to represent habitable spaces above and below the floor void) were consistent with theoretical approaches. c
31、) Adding floor covering above the floor and painting the ceiling under the floor alters the characteristics of the gas concentration build-up within the floor. The more sealed nature of the test results in higher gas concentrations within the floor assembly. d) The trends in gas concentration across
32、 the test floor were always in the order F1 F2 F3, F4 and F5. This was expected as the gas leak was in compartment F1 and F2 is the next compartment in the sequence. NOTE The test floor assembly comprised five compartments 3m long, 600mm wide and 241mm deep with knock outs removed from the I- joists
33、 to allow transfer of air and gas from one compartment into adjacent ones. These compartments were assigned designations F1, F2, F3, F4 and F5 with F1 containing the gas leak. Licensed Copy: London South Bank University, London South Bank University, Fri Feb 15 07:19:27 GMT+00:00 2008, Uncontrolled
34、Copy, (c) BSI BS 6891:2005 AMD 2 e) Gas concentrations in compartments F3, F4 and F5 were often similar and reflect the fact that penetrations were added to mimic the effect of plumbing and electrical services penetrating into the floor void. Increased ventilation and leakage was thus possible from
35、these three compartments. However, in the most sealed floor condition F3 was greater that F4 and F5. f) Measured gas concentrations in the upper (i.e. above the test floor) and lower (i.e. below the test floor) polythene shrouded volumes were typically lower than those in the floor cassette assembly
36、, reflecting the increased volume of the enclosure and potentially increased ventilation rates through the tape sealed joints. The measured values were often around the threshold levels for odorant detection. NOTE The polythene shrouded volumes above and below the test floor were to simulate the loc
37、ation of the floor within a home. g) The measured gas concentration in the lower volume was greater than the upper for all test cases except where the floor had the saw-cut and skirting added. h) For a gas leak rate of 19ml/min the build-up of gas within the test floor did not produce a gas concentr
38、ation greater than 2.5% gas in air, irrespective of floor condition, i.e. the degree of ventilation of the floor void. i) As anticipated, for gas leakage rates considerably in excess of (e.g. 30 ml/min) a minor gas leak, the build up of gas within the test floor did produce increased gas in air conc
39、entrations within the floor void. These concentrations were also affected by the degree of ventilation of the floor void. A copy of the full report may be obtained from Advantica, Ashby Road, Loughborough, Leicestershire LE11 3GR. Telephone 01509 282000; Facsimile 01509 283, quoting Advantica Report
40、 Number 6699 “GAS PIPES IN INTERMEDIATE FLOORS”. Any questions on the research project and its conclusions should be addressed to Advantica. Bibliography: Modify entry 7 thus: 7 INSTITUTION OF GAS ENGINEERS AND MANAGERS: UP/7, Edition 2, Gas installations in timber framed and light steel framed buil
41、dings, Loughborough: 2006 Add following entries to “Other publications“: 12 INSTITUTION OF GAS ENGINEERS AND MANAGERS: IGE/G/5, Gas in flats and other multi-dwelling buildings, Loughborough: 2006 13 ADVANTICA: Report Number 6699 Gas pipes in Licensed Copy: London South Bank University, London South
42、Bank University, Fri Feb 15 07:19:27 GMT+00:00 2008, Uncontrolled Copy, (c) BSI BS 6891:2005 AMD 2 intermediate floors, Loughborough: 2007 14 INSTITUTION OF GAS ENGINEERS AND MANAGERS: IGE/UP/1B, Tightness testing and purging of domestic sized Natural Gas installations, Loughborough: 1998 15 INSTITU
43、TION OF GAS ENGINEERS AND MANAGERS: IGE/UP/1, Soundness testing and purging of industrial and commercial gas installations, Loughborough: 1995 16 INSTITUTION OF GAS ENGINEERS AND MANAGERS: IGE/UP/1A, Soundness testing and direct purging of small low pressure industrial and commercial gas installations, Loughborough: 1998 Licensed Copy: London South Bank University, London South Bank University, Fri Feb 15 07:19:27 GMT+00:00 2008, Uncontrolled Copy, (c) BSI
链接地址:https://www.31doc.com/p-3726789.html