Linde specialty gases production and laboratory facilities perform professional and skillful quality control and analysis of gas mixtures. It is of vital importance that the results are correct. It is also important that all the information on the analysis certificate is correct and easy to understand.
All gas products are quality controlled. Where applicable, an analysis certificate is included in the product. If not included, it can be requested separately.
The following information can be found on the analysis certificate:
1. The date when the certificate was written, the beginning of the shelf life.
2. Identification of the analysis certificate.
3. Table of componets & concentrations:
- the unit can be given either in mole, volume or weight
- the uncertainty refers to the analysis of each component and is relative
- if an absolute uncertainty is given, this appears in the column ‘Analysis result’ (for instance 202 ± 4ppm).
4. Confidence level is the probability of the analysis result falling between the uncertainty limits.
5. The blend tolerance of a gas mixture specifies how close to the ordered concentration the final concentration must fall.
6. Shelf life: In a correctly handled cylinder, the component concentrations will remain within the limits stated in the analysis result during the stated shelf life.
7. Following the temperature recommendation improves safety and helps to keep the gas mixture homogeneous.
8. The component concentrations will remain within the limits stated in the analysis result down to the recommended minimum pressure of use.