1、BRITISH STANDARD BS3251:1976 Incorporated Amendment No.1 Specification Indicator plates for fire hydrants and emergency water supplies UDC 614.843.1:621.643.5-777BS3251:1976 This British Standard, having been prepared under the directionof the Fire StandardsCommittee was published under the authorit
2、y ofthe Executive Board on 30 April1976 BSI 03-1999 First published July1960 First revision April1976 The following BSI references relate to the work on this standard: Committee reference FSM/17 Draft for comment73/12574DC ISBN 0 580 09320 4 Co-operating organizations The Fire Standards Committee, u
3、nder whose supervision this British Standard was prepared, consists of representatives from the following Government departments and scientific and industrial organizations: Association of County Councils Association of Metropolitan Authorities British Constructional Steelwork Association British Fi
4、re Protection Systems Association Chief and Assistant Chief Fire Officers Association* Concrete Society Ltd Confederation of British Industry Department of the Environment* Department of the Environment and Fire Offices Committee Joint Fire Research Organization* Department of Trade Engineering Equi
5、pment Users Association Fire Extinguishing Trades Association* Fire Offices Committee Fire Protection Association Greater London Council* Health and Safety Executive Home Office* Industrial Fire Protection Association of Great Britain Institute of Heating and Ventilating Engineers Institution of Civ
6、il Engineers Institution of Fire Engineers* Institution of Municipal Engineers Ministry of Defence* National Council of Building Material Producers Royal Institute of British Architects The Government departments and scientific and industrial organizations marked with an asterisk in the above list,
7、together with the following, were directly represented on the committee entrusted with the preparation of this standard: Association of Road Traffic Sign Manufacturers British Fire Services Association British Plastics Federation British Valve Manufacturers Association National Water Council Amendme
8、nts issued since publication Amd. No. Date of issue Comments 6736 September 1991 Indicated by a sideline in the marginBS3251:1976 BSI 03-1999 i Contents Page Co-operating organizations Inside front cover Foreword ii Section 1. General 1 Scope 1 2 References 1 3 Definition 1 4 Marking 1 Section 2. De
9、sign 5 Dimensions 1 6 Character sizes 1 7 Presentation of information 1 8 Colour 2 Section 3. Materials and manufacture 9 Choice of materials 2 10 Characters 2 11 Removable characters 2 12 Finish 2 13 Protective painting 2 Section 4. Tests 14 Overall requirement 2 15 Numbers to be tested 3 16 Impact
10、 resistance test 3 17 Colour stability and resistance to weathering 3 18 Flexibility 3 19 Security of removable characters 3 20 Test certificate 3 Appendix A Recommendations for fixing indicator plates 4 Figure 1 Single class A hydrant indicator plate 4 Figure 2 Single class B hydrant indicator plat
11、e 5 Figure 3 Double class A hydrant indicator plate 6 Figure 4 Double class B hydrant indicator plate 7 Figure 5 Class C emergency water supply indicator plate 8 Figure 6 Class D meter bypass indicator plate 9 Figure 7 Removable digit and spacer piece 10 Publications referred to Inside back coverBS3
12、251:1976 ii BSI 03-1999 Foreword This revision of BS3251 supersedes the 1960 version and, as part of BSIs programme of metrication, is expressed in metric terms. The metric values are in SI units; for further information reference should be made to BS 3763 “The International System of units (SI)”. T
13、his revised standard, besides introducing a design of plate for displaying information in metric terms, also introduces fresh requirements for plates to indicate the direction and distance of emergency water supplies and the distance of the valve controlling a meter bypass. In addition separate requ
14、irements for plates for use on motorway roads are included. It is not intended that existing plates which are marked in imperial units should be replaced immediately with metric plates conforming to this standard. The metric markings of the new plates are sufficiently distinctive to avoid confusion
15、with existing plates which are marked in imperial units and therefore plates of the latter type may continue in use so long as their condition is satisfactory. Self-adhesive hydrant indicator stickers are not covered by this standard as their form of construction and fixing is different from that fo
16、r rigid plates. However, these stickers should conform to the requirements given in this standard concerning the method of displaying the necessary information, i.e.size of letters and digits and colour of the indicator. The standard does not specify requirements for fixing the plates as these requi
17、rements will vary greatly according to circumstances. However, for the guidance of users of plates that comply with the requirements of this standard, some important considerations concerning the method of fixing the plates are given in Appendix A. Certification. Attention is drawn to the certificat
18、ion facilities described on the inside back cover of this standard. A British Standard does not purport to include all the necessary provisions of a contract. Users of British Standards are responsible for their correct application. Compliance with a British Standard does not of itself confer immuni
19、ty from legal obligations. Summary of pages This document comprises a front cover, an inside front cover, pages i and ii, pages1 to 10, an inside back cover and a back cover. This standard has been updated (see copyright date) and may have had amendments incorporated. This will be indicated in the a
20、mendment table on theinside front cover.BS3251:1976 BSI 03-1999 1 Section 1. General 1 Scope This British Standard specifies requirements for hydrant, emergency water supply and meter bypass indicator plates made from sheet steel, cast iron, aluminium alloy or plastics materials, together with all r
21、emovable characters and spacer pieces supplied with them. Four types of plate are specified. a) Class A plates: hydrant indicator plates for general use except on roads of motorway standard. b) Class B plates: hydrant indicator plates for use on roads of motorway standard. c) Class C plates: indicat
22、or plates for emergency water supplies, “EWS”. d) Class D plates: indicator plates for meter bypass valves. 2 References The titles of the British Standards referred to in this standard are listed on the inside back cover. 3 Definition For the purposes of this British Standard the following definiti
23、on applies. character a term which includes all letters, digits, arrows and other indicating marks on the front surface of the plates. A character may be flush, raised, recessed or removable 4 Marking Indicator plates complying with all the relevant requirements of this standard shall be marked with
24、 the BSnumber, i.e.BS3251. Section 2. Design 5 Dimensions 5.1 Indicator plates shall conform to the dimensions shown in the figures as follows. Class A plates to Figure 1 Class B plates to Figure 2 Class C plates to Figure 5 Class D plates to Figure 6 5.2 Where, however, it is desired to indicate th
25、at double hydrants exist, double hydrant indicator plates shall be used conforming to the dimensions shown in the figures as follows. Class A plates to Figure 3 Class B plates to Figure 4 5.3 In all cases where removable digits or spacer pieces are required these shall conform to the dimensions show
26、n in Figure 7. 5.4 When plates are required to fit both165mm and150mm vertical fixing centres the slots shown in Figure 1 to Figure 6 shall be suitably elongated to accommodate 150mm centres. 5.5 The tolerances for all the dimensions shall be 0.5mm, except that for the apertures for removable charac
27、ters they shall be +0.5, 0mm and for the removable characters they shall be+0, 0.5mm. 6 Character sizes 6.1 For class A plates characters shall conform to the sizes shown in Figure 1, Figure 3 and Figure 7. 6.2 For class B plates the characters shall conform to the sizes shown in Figure 2, Figure 4
28、and Figure 7 except that the lettering in the part of the plate below the “H” or “HD” shall be as large as can conveniently be fitted into the space available while ensuring that all essential information is included. Preferably the letters of the principal words should be 40mm high. 6.3 For class C
29、 plates the lettering should preferably conform to the sizes indicated in Figure 5 but may be varied to suit the circumstances. The direction of the arrow shall be as clearly shown and the arrow itself be as large as the available space permits. 6.4 For class D plates the lettering shall conform to
30、the size shown in Figure 6. 7 Presentation of information 7.1 Class A and class B plates shall carry, on the upper part of the plate, two or three digits giving the nominal internal diameter of the water main in millimetres, and, on the lower part of the plate, one or two digits indicating the dista
31、nce of the hydrant from the plate to the nearest metre. 7.2 Class B plates shall carry an address as shown in the example illustrated in Figure 2. If appropriate, an arrow may be added or substituted which shall be arranged to give the closest possible indication of the direction in which the hydran
32、t lies. 7.3 Class C plates shall carry an address and an indicating arrow as shown in the example illustrated in Figure 5. The approximate distance of the emergency water supply shall be shown in metres. The relative position of the arrow, the digits indicating distance and the extent of definition
33、of the local feature may be varied to suit the conditions at the site. In particular, the arrow shall be arranged to give the closest possible indication of the direction in which the water supplies lie.BS3251:1976 2 BSI 03-1999 7.4 Class D plates shall carry one or two digits indicating the distanc
34、e from the plate in metres of the valve controlling the meter bypass. 8 Colour 8.1 All characters shall be black. 8.2 The remainder of the front surface of all plates shall conform to colour reference no.309(canary yellow) in BS381C. Section 3. Materials and manufacture 9 Choice of materials The mat
35、erial from which indicator plates are made shall be selected and specified by the purchaser from the following alternatives. a) Steel: vitreous enamelling quality mild sheet steel. b) Cast iron: complying with the requirements of BS1452 grade 10or better. c) Plastics: plastics materials either self-
36、coloured or capable of being indelibly coloured and which, after processing, satisfy the tests described in section 4. 10 Characters Unless otherwise specified, it is at the option of the manufacturer as to whether characters are flush, raised, recessed or removable to suit the design of the plate.
37、In this connection the term “flush characters” shall include those characters formed solely by the finishing process, e.g.vitreous enamelled characters on a flat surface. 11 Removable characters Where removable characters are held in position by a mechanical fixing, any fixing and its method of atta
38、chment shall be compatible with the material of the plate in order to avoid electrolytic corrosion. Metal fixings shall be protected in a manner similar to that required for the plate and any securing screws or rivets shall comply with the requirements of A.1, A.2 and A.3 in so far as material and p
39、rotective coating are concerned. 12 Finish 12.1 The plates shall be smoothly finished, free from defects and of a general quality acceptable as good practice for the material employed. 12.2 Metal plates may be finished in stove enamel, vitreous enamel or in reflecting material. 12.3 Plastics materia
40、ls may be finished by the application of colour, or the pigments may be combined with the material, or a reflecting material may be used. If used, the reflecting material shall conform to the performance and test requirements of BS873. 12.4 Aluminium alloy plates shall be either stove-enamelled or b
41、itumen coated on the back. NOTEAll plates should be finished on front and back to withstand weather and any other corrosive conditions prevalent in the location where they are to be fixed. 13 Protective painting Except where the finishes permitted in12.2 and12.3 are concerned, all plates shall be pr
42、otected by painting according to the following procedure. a) Surface preparation. The plates shall be cleaned free of all dust, sand, rust or corrosion products, and shall be free of all oil, grease or moisture. b) Painting process. The back of the plate (except aluminium alloy plates see12.4) shall
43、 receive one coat of priming paint and the face one coat of priming paint and one coat of yellow finishing paint. Characters shall be picked out with one further coat of black finishing paint and removable characters and spacer pieces shall receive the same full treatment as the plates. The thicknes
44、s of each coat shall be not less than0.2mm. c) Type of paints. The priming paint shall contain an effective proportion of inhibiting pigment (for aluminium paints, this pigment shall not be lead). The finishing paints shall be of a suitable pigmentation to give satisfactory durability and a stable,
45、light-fast colour to comply with the colour requirements of clause8. Section 4. Tests 14 Overall requirement All plates shall be capable of passing the tests described in clauses16 and17. In addition, plastics plates shall be capable of passing the tests described in clause18. Aluminium alloy: for c
46、astings complying with the requirements of BS1490 type LM4 or LM6. for pressings complying with the requirements of BS1470 type NS 3 or NS 4.BS3251:1976 BSI 03-1999 3 15 Numbers to be tested Except for the impact resistance test for which two plates of each type shall be tested, the manufacturer sha
47、ll test a minimum of four of each type of plate before commencing manufacture in quantity. Provided all the tested plates prove satisfactory and provided there is no change in the materials used, or in the method or conditions of manufacture, all subsequently produced plates of that type may (unless
48、 shown to the contrary) be deemed to comply with the requirements of this standard. If the purchaser requires additional tests these will be at his expense. 16 Impact resistance test 16.1 The test shall be carried out at 20 5 C and two sample plates shall be tested. One plate, or a representative po
49、rtion of it including a character, shall be supported on three12.5mm diameter steel balls inserted to a depth of6.5mm in a steel or cast iron circular base about250mm diameter and75mm thick. The steel balls shall be equally spaced on a75mm diameter circle concentric with the base. A recess of50mm diameter and not less than6.5mm deep shall be provided concentrically inside the circle of steel balls, to permit flexure of the plate. The plate, or its representative portion, shall be so positioned that its approximate centre, which shall not coincide with the
