Clean ducts. Rena kanaler.

Reports on symposium in Belgrade, 1978, on the consequences of blocked and contaminated ventilation ducts. Notes current research by Swedish Building Research Council into hospital ventilation systems and other work on aspects of contamination and its effect on efficiency. Also reports on investigations into ventilation in housing. Diagrams illustrate various parameters and the effect of cleaning and contamination on airflow and efficiency. Considers economic periodicity of cleaning. Stresses importance of cleaning heat exchangers. Article concludes with a subject bibliography.