The aim of the diurnal lightning proposal is to rectify rooms' access to sunlight, which is dispersed in the atmosphere, and to rectify the visual comfort of the users of the interior during daylight hours; i.e. the appropriate lightning conditions for visual work carried out in the interior. The specifications of diurnal lightning are formulated in IEC-730580-1 to 4. These specifications are binding because the relevant articles mentioned in the standards are determined as binding laws and decrees 268/2009 on the technical requirements for construction, 258/2000 on Public Health, 410/2005 on hygiene requirements for educational facilities and the education of children, Government Decree 361/2007 on sanitary conditions at work. In situations where controls of calculations of measurements are not possible or too difficult, it is then necessary to maximise the transparency of computational procedures. In particular, it is necessary to include all the variables that enter into the calculation (factors of brightness shading barriers, factors of transmission and reflection of light). When assessing the accuracy of the calculations, it is also necessary to require detailed descriptions of the computational models used in determining the individual components of the diurnal lightning factors.