Radon is an inert radioactive gas released into the atmosphere from certain minerals and man-made products in which it is produced. It can accumulate in confined spaces. Radon emanation into a building can come from: the underlying soil, the building materials, tap water and natural gas. The principal isotope, 222Rn, decays to products which if inhaled can result in exposure of the respiratory tract to alpha radiation. The decay products, radon daughters, are significant because of their potential to cause health effects.
The acoustic environment was investigated in an office building with a history of occupant complaints. A scoring system was developed for rating occupants' sick building symptoms. High scores were associated with the occurrence of high levels of infrasound (< 20 Hz) in the rooms, und low levels with low scores. The infrasound came from the ventilation system as airborne noise, rather than structural-borne vibration. Levels of infrasound were often amplified in the tightly sealed rooms, and could be higher at work stations than at supply grilles.
House depressurization is a ubiquitous, dangerous problem. As regional mechanical codes move toward consolidation into one International Mechanical Code, now is the time to add a performance testing requirement for house depressurization.
Providing safe storage for documents and documentary records within new and existing buildings is a problem faced by many building designers and owners/managers. This Bulletin sets out the common causes of damage and the specific storage criteria for commonly used documents and documentary records, as well as outlining methods to satisfy these criteria.
The issue of sound quality in offices and other occupied spaces has been of continuing interest since the 1950s. Existing assessment methods do not adequately account for the Low-frequency background sound ( < 250 Hz) produced by operating heating, ventilating, and air-conditioning (HVAC) systems, in particular, Low-frequency rumble. This paper discusses the results of ASHRAE-sponsored research in which more than 75 HVAC noise samples were collected, normalized, and categorized in terms of sound quality.
Fans and their associated ventilation ducts are amongst the major sources of airborne noise encountered within a submarine. Health & Safety Standards require that the ship's crew are not exposed to unnecessary high levels of noise and have a suitable environment free from intrusive noise in order to work and rest. The problem with noise emitted from fans and ducts in submarines can be categorised as follows:
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