ISO 16232-6 pdf download Road vehicles — Cleanliness of components of fluid circuits — Particle mass determination by gravimetric analysis
6.2 Health and safety
6.2.1 General Local Health and Safety procedures shall be followed at all times, any equipment shall be operated in accordance with the manufacturer’s instruction and personal protection equipment used where appropriate.
6.2.2 Chemicals used in the procedures can be harmful, toxic or flammable. Good laboratory practices shall be observed in the preparation and use of these chemicals. Care shall be taken to ensure compatibility of the chemicals with the materials used (refer to each Material Safety Data Sheet [MSDS]). Follow the precautions for safe handling and usage as described in the MSDS available from the supplier.
6.2.3 Volatile liquids: Care shall be taken with flammable liquids to ensure that they are used in accordance with the MSDS, at temperatures below the stated flash point and away from potential sources of ignition. Appropriate precautions should be taken to avoid inhalation of fumes from these solvents. Always use suitable protective equipment.
6.2.4 Electrical: Appropriate care should be applied in the use of electrical power.
6.2.5 Static: the build-up of electro-static charges (created by friction as fluids flow) shall be dissipated and not be allowed to build- up where it can discharge and create a spark. An earthing strap shall be provided where there is a risk, especially for the vacuum where often volatile liquids are involved.
6.2.6 Disposal all liquids and substances shall be disposed of in accordance with local environmental procedures. In the event of spillage it shall be cleaned-up in the manner detailed in the MSDS.
7 Lower detection limit for gravimetric analysis Where objects are weighed using balance with an accuracy of at least ± 0,1 mg in rooms with uncontrolled conditions as far as temperature and relative humidity are concerned, the lower detection limit is 1 mg. With a blank requirement of less than 10 % of the final mass, the residual mass (m F ) shall be at least 10 mg in order for it to be accurately weighed.
In practice, the possibility to analyse gravimetric levels below 10 mg in an uncontrolled environment should not be excluded. In this case, blank values below 1 mg are acceptable to analyse a contaminant mass between 3 mg and 10 mg. Report the blank value as being “< 1 mg”.
When using a five or six digit balance with an accuracy of at least 0,01 mg in rooms with controlled temperature and relative humidity, it is possible to detect blank values < 1 mg.
For this reason, analysis of a contaminant mass of < 10 mg respecting the 10 % criterion is possible. For the case of very low gravimetric level, another alternative method of inspecting components could be to increase the residual mass (m F ) by performing extraction on several components simultaneously or by filtering the analysis liquid collected from several components through one membrane filter.
8 Preparing the apparatus
8.1 Conditioning of equipment Prepare clean filtration equipment, membrane filter holders, collection and rinsing vessels, tweezers and analysis equipment. The required cleanliness level of the equipment shall be such that the equipment will not contribute significantly to the overall result and shall be consistent with the presumed cleanliness of the component to be tested.
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