7057 International Standard (ISO INTERNATIONAL ORGANIZATION FOR STANDARDIZATION·MEKAYHAPOAHAR OPIAHW3ALMR HO CTAHAAPTM3AMW-ORGANISATION INTERNATIONALE DE NORMALISATION ANst Innermat Do Se Plastics laboratory ware - Filter funnels Materielde laboratoire en plastique-- Entonnoirs pour filtration First edition - 1981-09-01 SEP 0 9190 ISO 7057-1981 (E) UDC 542.231.6 : 678.5/.8 Ref. No. 1SO 7057-1981 (E) Descriptors : glassware, laboratory glassware, plastic products, filters, funnels, dimensions, construction, tests, determination, flexibility, conductivity. Price based on 5 pages No reproduction or networking permitted without license from IHS Not for Resale Foreword ISO(theInternational OrganizationforStandardization)isaworidwidefederationof national stanidards institutes (Iso member bodies). The work of developing Inter- national Standards is carried out through Iso technical committees. Every member body interestedinasubjectfor.whicha technical committeehasbeensetup hasthe right to be represented on that committee. International organizations, governmental and non-governmental, in liaison with Iso, also take part in the work. Draft International Standards adopted by the technical committees are circulated to the member bodies for approval before their acceptance as International Standards by the ISo Council. InternationalStandardISO7057wasdevelopedbyTechnicalCommitteeISO/TC48 Laboratory glassware and related apparatus, and was circulated to the member bodies in May:1980. It has been approved by the member bodies of the following countries : Australia Hungary Romania Brazil Italy South Africa, Rep. of Czechoslovakia Korea,Rep.of Spain Egypt, Arab Rep. of Mexico United Kingdom France Netherlands USSR Germany, F. R. Poland The member body of the following country expressed disapproval of the document on technical grounds : India International OrganizationforStandardization,1981 Printed inSwitzerland Provided by IHS underlicense with Isc No reproduction or networking permited without license from IHS Not for Resale ISO 7057-1981 (E) INTERNATIONALSTANDARD Plastics laboratory ware -- Filter funnels 0 Introduction 3 Material This International Standard has been prepared to align' the 3.1 General requirementsforplastics filterfunnels withthoseforgiassfilter funnels which will form the subject of ISo 4798. In both cases, Filter funnels shall be rigidly constructed of generally non-brittle the requirements have been based on the sizes of filter papers plastics material of suitable chemical and thermal properties, currently available, i.e. diameters 55 - 70 - 90 - 110 - and shali be as free as possible from moulding defects and 125-150-185and240mm. stress. Differences between the requirements for plastics and glass filter funnels have been limited, as far as possible, to those 3.2 Resistance to extraction of ionic material by arising from the differences in physical properties of the re- water at 60 °c spective materials used in their construction. When tested by the method specified in annex A, the funnel The requirements are applicable to filter funnels intended for shall give an aqueous extract free of suspended matter, and usei with aqueous solutions at temperatures between 0 and having a conductivity not more than 200 μS/m greater than 60 c. Before using these filter funnels for strong acids and that of the original water used for the extraction. alkalis,oxidizing agents or non-aqueous liquids,or at temperatures outside this temperature range, users should NOTE 200 μS/m is equivalent to the conductivity of water satisfy themselves that the filter funnels are suitable for such containing approximately 1 mg/l of sodium chloride. applications either by laboratory tests or by reference to the manufacturer or supplier. Plastics filter funnels complying with the requirements of this International Standard are marked 4 Dimensions both with a recommended maximum temperature of use and an The dimensions of the preferred sizes are given in ta