BS EN ISO 10704:2019 pdf free.Water quality – Gross alpha and gross beta activity- Test method using thin source deposit.
Gross alpha and gross beta activity can be measured using either a silicon surface barrier (SSB) detector or a proportional counter (windowless). Ion-implanted Si detectors and window-proportional counters (between 80 pg cm-2 to 400 pg cm-2) may also be used. Gross alpha and gross beta activity can also be counted using a silver-activated zinc sulfide scintillation screen and plastic scintillation detector, respectively.
6 Sampling
Sample, handle and store water samples in accordance with ISO 56ZJ. and IS56623. Additional information on sampling of different types of waters can be found in the relative parts of the ISO 5667 series[9lLWl11[I2IlUJlI4JI11L1l.
The laboratory sample is not usually acidified as the test portion is directly evaporated on the planchet. Acidification minimizes the loss of radioactive material from solution by adsorption on the wall of the vial, but is done after filtration, as otherwise it desorbs radioactive material already adsorbed on the particulate material and, also, increases the salt content of the test sample, and thus the thickness of the deposit. If necessary, concentrated nitric acid can be used (it is recommended to avoid hydrochloric acid).
7 Procedure
7.1 Preliminary
Calculate the volume of laboratory sample for gross alpha measurement, i.e. the volume of the test portion, in order to produce a deposit with a surface density lower than S mg cm-2 on the planchet. For deposits of surface density below 5 mg cm-2, self-absorption phenomena can be neglected for gross beta measurement except when using low energy beta emitter such as 137Cs for calibrationliZi.
When using the same deposit for the simultaneous gross alpha and gross beta measurement, the planchet surface density limit for alpha activity determinations applies.
7.2 Source preparation
IMPORTANT — Due to the ingrowth of radon decay products overtime, the results are dependent on the time elapsed between sample preparation and measurement. For comparison purposes, It Is recommended that the measurement be performed at the same time after the preparation of the sample.
7.2.1 Preparation of planchet
Degrease planchets (5,222) using a solvent or a surfactant to ensure that the test portion is well distributed over the entire surface and consequently that there is a deposit of uniform surface density bonded to the planchets. Some suppliers degrease planchets at the end of a cycle of fabrication and deliver, on demand, a certificate of attestation.BS EN ISO 10704 pdf download.
Tags: Water quality
-
ISO 8600-1-2013 pdf free download.Endoscopes – Medical endoscopes and endotherapy devices – Part 1: General requirements. 6 Marking 6.1 Minimum marking Iach individual endoscope or endotherapy device shall have the lollowing minimum marking: a) model number and/or other mark sufficient to identify the endoscope or endotherapy device and its manufacturer; b) maximum insertion portion width, minimum instrument channel width, working length, field of view and/or direction of view where such identification is necessary for the intended use of the endoscope or endotherapy device. The Insertion portion width and instrument channel width units shall be in millimetres. The insertion portion width and instrument channel width can also be marked in French size as defined in 3.5, shown by either ‘Fr or an encircled number; c) wherever reasonable and practicable. the endoscope or endotherapy device and detachable component(s) shall be identified in terms of lot numbers or serial numbers, etc. 6.2 Marking legibility The marking shall remain legible over the lifetime of the device when the endoscope or endotherapy device is used, cleaned, disinlected, sterilized and stored in accordance with the instruction manual. 6.3 Marking exceptions When marking on the endoscope or endotherapy device or detachable component(s) is impossible to achieve due…
-
ISO 15688-2012 pdf free download.Road construction and maintenance equipment – Soil stabilizers 一 Terminology and commercial specifications. This International Standard establishes the terminology, definitions of operation and commercial specifications for soil stabilizers and their components intended for use in road construction and pavement works. It does not apply to soil stabilizers used in agricultural applications. 2 Normative references The following documents, in whole or in part, are normatively referenced in this document and are indispensable for its application. For dated references, only the edition cited applies. For undated references, the latest edition of the referenced document (including any amendments) applies.. ISO 3911, Wheels and rims for pneumatic tyres — Vocabulary, designation and marking ISO 6746-1, Earth-moving machinery — Definitions of dimensions and codes — Part 1: Base machine ISO 6746-2, Earth-moving machinery — Definitions of dimensions and codes — Part 2: Equipment and attachments ISO 7134. Earth-moving machinery — Graders — Terminology and commercial specifications 3 Terms and definitions For the purposes of this document, the following terms and definitions apply. 3.1 soil stabilizer self-propelled machine, either towed or transported, with the function of pulverizing, breaking-up, aerating, homogenizing, and loosening existing and imported soil or paving materials and mixing them…
-
ISO 18436-1-2012 pdf free.Condition monitoring and diagnostics of machines – Requirements for qualification and assessment of personnel一 Part 1: Requirements for assessment bodies and the assessment process. 5 Requirements for assessment body personnel 5.1 General provisions In order to ensure that the assessment process is carried out effectively and uniformly, the competence requirements for personnel involved in the entire process shall be defined by the assessment body and, in the case of a third party, be approved by the responsible TCC (in accordance with ISO/IEC 17024). The assessment body shall require its personnel (internal or external) to sign a contract, or other document, by which they commit themselves to comply with the rules defined by the assessment body, including those relating to confidentiality and those relating to independence from commercial and other interests, and from any prior or present link with the persons to be examined that would, in the opinion of the interested parties, compromise impartiality. Clearly documented instructions shall be available to the personnel, describing their duties and responsibilities. These instructions shall be maintained up to date. All personnel involved in any aspect of assessment activities shall possess appropriate educational qualifications, experience and technical expertise, which satisfy defined…