Stability of the apparatus. 4.2.1. The light source and photometer head should remain stable throughout the period of the test. Since the sensitivity and the adaptation to the V (λ) function of most photometer heads change with temperature, the laboratory ambient temperature should not vary significantly during this period. Sufficient time should always be allowed for the apparatus to stabilize before commencing measurements. 4.2.2. A useful check on the overall stability of the reflex photometer during a series of tests is to make periodic measurements of RI values of a stable reference standard.
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Samples: Agreement Concerning the Adoption of Harmonized Technical United Nations Regulations for Wheeled Vehicles, Agreement Concerning the Adoption of Harmonized Technical United Nations Regulations for Wheeled Vehicles
Stability of the apparatus. 4.2.13.2.1. The light source and photometer head should remain stable throughout the period of the test. Since the sensitivity and the adaptation to the V (λ) function of most photometer heads change with temperature, the laboratory ambient temperature should not vary significantly during this period. Sufficient time should always be allowed for the apparatus to stabilize before commencing measurements.
4.2.2. A useful check on the overall stability of the reflex photometer during a series of tests is to make periodic measurements of RI values of a stable reference standard.
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Samples: Agreement Concerning the Adoption of Uniform Technical Prescriptions for Wheeled Vehicles
Stability of the apparatus. 4.2.1. The light source and photometer head should remain stable throughout the period of the test. Since the sensitivity and the adaptation to the V (λ) function of most photometer heads change with temperature, the laboratory ambient temperature should not vary significantly during this period. Sufficient time should always be allowed for the apparatus to stabilize before commencing measurements.
4.2.2. A useful check on the overall stability of the reflex photometer during a series of tests is to make periodic measurements of RI values of a stable reference standard.
Appears in 1 contract