Mercury known and unknown - Part 2
The previous part of this article (Světlo 4/2014 pp. 44-46) was a mosaic of known and lesser known properties of mercury. This section reviews several methods for measuring mercury in different environments. Specialized co-authors have taken up the approach to most of them. RNDr. Alice Dvorská, Ph.D. Measurement of atmospheric mercury concentrations Unique measurements of atmospheric mercury concentrations are carried out at the [...]
Colour rendering scales
Ra, CQS, GAI, CRI2012, FSI... Is it even possible to express the colour fidelity of artificial light with a single number? Why is it necessary to evaluate the colour rendering of light sources? "It is essential for visual performance, general well-being and mental well-being that the colours of objects and human skin in a given environment are rendered naturally, faithfully and in such a way that people look attractive [...]
Did you know that luminaires don't just emit light? What about electromagnetic interference from luminaires?
Dentistry is undoubtedly one of the most visually demanding professions. For the most natural working environment in the dental office, balanced lighting of the entire room is also crucial, an indispensable part of which is the pendant light above the chair. However, this is kept close to the doctor's head throughout the day. Every device that works with electricity emits an electric and magnetic field. As a species, [...]
Mercury known and unknown - Part 1
Mercury is a neurotoxic heavy metal and has a bad reputation in the public mind. Customers buying lamps are concerned about its effects on their health. However, for light sources such as fluorescent lamps or mercury lamps, mercury is completely indispensable. End-of-life light sources need to be disposed of properly so that they do not become a burden on the environment. Let's talk about this [...]
Dental office lighting: the overlooked requirements of the 2012 lighting standard
We take in more than 80% of information by sight, so proper lighting plays a vital role in virtually all human activities. In healthcare, the most noble values such as human health and life are at stake. The lighting of dental surgeries is governed by the technical standard ČSN EN 12464-1 specifying the minimum lighting of working areas,[1] which is made mandatory by Act No. 61/2007 Coll.[2] The [...]
Light and biological clock
Introduction Time rhythms can be found throughout the living realm. Circadian (from Latin circa - around, dies - day) or approximately daily rhythms have been mentioned several times in the magazine Světlo - e.g. in issues 1 and 3/2005 or 5 and 6/2008. The term circadian was introduced in the 1950s by Franz Halberg, one of the founders of chronobiology, [...]
