BS EN ISO 1833-18:2019 Textiles. Quantitative chemical analysis Mixtures of silk with other protein fibres (method using sulfuric acid)

Mixtures
Fibre testing (textiles)
Textile testing
Wool fibres
Determination of content
Silk
Chemical analysis and testing
Quantitative analysis
Extraction methods of analysis
Hair (animal)
Textile fibres
Wool
Chemical tests (textiles)

Link: BS EN ISO 1833-18:2019 Textiles. Quantitative chemical analysis Mixtures of silk with other protein fibres (method using sulfuric acid)
Source: BSI Standards

BS ISO 13653:2019 Optics and photonics. General optical test methods. Measurement of relative irradiance in the image field

Ophthalmology
Optical measurement
Optical properties of materials
Test equipment
Optics
Radiant flux density
Graphic representation
Designations
Ophthalmic equipment
Test specimens
Optical instruments

Link: BS ISO 13653:2019 Optics and photonics. General optical test methods. Measurement of relative irradiance in the image field
Source: BSI Standards