A r a ş t ı r m a I NTERNATIONAL DEVELOPMENT OF STANDARDS FOR VENTILATION BUILDI NGS Standing Standard Project Committee 62 (SSPC 62) has been working since 1990 on a revision ofANSI/ASHRAE Standard 62-1 989, "Ventilation for Acceptable lndoor Air Quality." The revised draft puts more emphasis on indoor air quality than the existing standard. in addition to a ventilation rate per person, the draft alsa requires an additional ventilation rate based on floor area to account for any pollution emitted from the building or from the HVAC system itself. The draft alsa emphasizes air cleaning, ventilation effectiveness, and system requirements. Other additions are sections on documentation, commissioning, operation and maintenance, and residential ventilation. While the existing standard does not distinguish between smoking and non-smoking except in smoking lounges, the revision assumes the absence of smoking. The revision, however, includes a separate annex to calculate the ventilation rate when smoking occurs. During the same period, groups in other countries have been writing new or revising existing standards or guidelines for ventilation of buildings. üne of these groups is CEN, the European standards organization. A CEN working group under technical committee TC 156, "Ventilation for Buildings," has developed a document prENV 1752, "Ventilation for Buildings: Design Criteria for the lndoor Environment" (CEN 1996), which alsa has been out for public review. The final vote has not been made. This is planned to be a European prestandard, which means it will be available for use in practice for a two-year trial. it will then be decided by the CEN member countries whether the standard, including modifications, will be adopted as a full standard. lf adopted, all European countries must adopt it as a national standard. Europen standards have the same relative status as ANSI standards. European standards are voluntary documents that are regarded as state of the art, but not law. The standards are, however, often referred to in building regulations and in this way may become legal documents. in addition to CEN, groups in GermanY, UK and Scandinavia alsa have been developing national standards or guidelines for ventilation in buildings. in the UK, CIBSE (Charter lnstitute of Building Service Engıneers) has made a review draft of Guide A, sec. 2 "Environmental Criteria for Design" (CIBSE 1993). The German Standards Organization, DiN, has published a revision of DiN 1946, Part 2 "Ventilation and Air Conditioning: Technical Health Requirements" (DiN 1994). This paper compares the requirements in these proposed By Bjarne W. Olesen, Ph. O. Member ASHRAE standards or guidelines. There are some differences in the scopes of the documents, therefore they are not directly comparable. AII, however, include a minimum ventilation rate which is the focus of this comparison. Purpose and Scope The purposes of ASHRAE Standard 62-1989R are: a) to define the roles of and requirements for ventilation, source management, and air cleaning in providing acceptable indoor air quality; b) to specify methods for determining minimum ventilation rates; c) to specify ventilation system design, operational, and maintenance requirements for various types of indoor spaces. This is similar to the purposes of the other documents; but with some significant differences. The main use of all the standards is the design of ventilation systems. While ASHRAE goes into detail with requirements of mechanical systems, the other standards mainly deal with requirements as seen from the occupants perspective. The other documents include parameters such as thermal environment, and noise and illumination levels. Table 1 shows a comparison of the scopes. Table 2 lists the contents. ASHRAE 62-1989 R is written in code language using mandatory words such as "shall" and "must". ASHRAE and CIBSE both include requirements for ventilation in residential buildings, while DiN and CEN have or are developing separate standards for residences. While ASHRAE and DiN have very detailed requirements for the system and its components, the requirements in CEN and CIBSE relate only to the indoor environment. CEN, however, is developing several standards with requirements or test methods for the components of a ventilation system. The following sections present the methods and requirements for the minimum ventilation rate: Definition of Acceptable l ndoor Air Qual ity Each of these documents uses terms such as "indoor air quality", "perceived air quality'', "acceptable indoor air quality' and "percentage of dissatisfied persons", but only ASHRAE gives a clear definition of the terms used: Acceptable indoor air quality; air in an occupied space towards which a substantial majority of occupants express dissatisfaction and in which there are not likely to be 103
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