High colour temperature lighting for institutionalised older people with dementia

Non-pharmacologic interventions, such as high-intensity white light with a high output in the short-wavelength part of the spectrum can play an important role in the care for older people with dementia. In order to assess the effects of prolonged exposure to low intensity light, i.e., E < 500 lx, from a light source with a high correlated colour temperature (17,000 K versus 2700 K) on behaviour and circadian rhythmicity of institutionalised older adults with dementia, a cross-over design field study was carried out in a psychogeriatric day care ward in May and June 2008. Effects of the lighting intervention were assessed by the Dutch Behaviour Observation Scale for Intramural Psychogeriatrics (GIP), and tympanic temperature measurements. The two lighting solutions installed, particularly the 17,000 K lighting, led to much lower colour temperatures at eye level in practice. No significant improvements in behaviour and in the range of tympanic temperature were found for the lighting interventions tested. This might indicate that higher illuminance levels are the important factor in establishing successful light therapy, and that higher colour temperature may add up to the effectiveness. At the same time, the 17,000 K light tubes did not result in ultrahigh colour temperatures at the eye level of the subjects, and may even have an adverse effect on some persons with dementia.     

Financial and energy impacts of compact fluorescent light bulbs in a rural setting

Within the context of a national campaign to replace GLS with CFLs, a pilot study was undertaken in Niha, Lebanon to replace around 1000 light bulbs. This paper reports on the detailed savings actually obtained by this project. Energy savings were found to be 8.3%. The obtained savings were lower than the theoretical savings expected mainly due to apparent lower time of use than expected prompting a more moderate advertised yearly savings. The beneficiaries’ attitude towards CFLs was assessed and the results indicate a general satisfaction and willingness to purchase CFLs. One major drawback has been the dissatisfaction with light intensity. The impact of the campaign on other village residents was assessed and the campaign was successful in convincing one third of the population to install CFLs and two thirds said that they intend to buy CFLs in the future. A new approach in the campaign for CFL promotion is suggested.