ANSI/ASHRAE Standard (Including ANSI/ASHRAE Addenda listed in Appendix H). Ventilation for Acceptable. Indoor Air Quality. Ventilation standards and mechanical codes have evolved to address ASHRAE Standard (2). Ventilation for .. ASHRAE Standard The Ventilation Rate Procedure found in ASHRAE Standard Addendum N was applied to Monmouth University’s Multipurpose Athletic.
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For example, studies have shown that gases such as formaldehyde, which are present in many common office materials, may not be adequately diluted under CO2 DCV strategies without an extensive pre-purge cycle prior to occupancy. Designers claiming this procedure must be able to substantiate that rates are maintained during all load conditions.
Therefore methods that lag occupancy such as CO2 DCV should be carefully considered prior to implementation. The statement, “in the absence of wind and stack effect” is of concern since external factors can significantly influence infiltration and exfiltration across the building envelope. Other distinguishing factors include a provision for zone distribution effectiveness based on the air distribution configuration, the modification of the multi-space equation for multi-zone recirculating systems, the consideration for varying operating conditions, the provision for dynamic reset, and specific requirements for exhaust ventilation.
Unfortunately, almost every facility has contaminants generated from within the space i. Studies have indicated that a ventilation rate of 15 CFM per person is adequate to dilute body odor. Noteworthy is the standard’s definition of acceptable indoor air quality.
ASHRAE Standard | Midwest Air Filter
The principal comment regarding 6. In addition, increased humidity combined with wind and stack driven infiltration during periods when the ventilation system is not operating may be a significant factor influencing mold and fungal growth.
Advanced VAV control strategies can satisfy the requirements of 6. It incorporates both quantitative and subjective evaluation. CO2 is an indicator of human activities and hence “bioeffluents” and not a measure of indoor air quality.
Requiring only a “snap-shot” of airflow rates is analogous to providing a one-time setup for temperature control, which obviously would not be very effective. However, contaminants that are not appreciably reduced by the air-cleaning system may be 6-22001 controlling factor in design and prohibit the reduction of air below that set by the Ventilation Rate Procedure.
Interpretations for Standard 62-2001
Maintaining a building at net neutral pressure under these conditions would be more appropriate. In reality, most systems require permanent airflow measurement devices to assure compliance with the standard. Systems that provide a variable volume of supply air to the conditioned space are influence by everything previously mentioned.
Moisture is a prerequisite for mold and fungal growth and the condition should be avoided. Great care should be given to the selection between these procedures. Variable asbrae can either be detected by a.
Whenever the temperature of a building envelope is lower than the dew point of air migrating across it, there will be condensation. Especially in facilities with variable occupancy and activity levels. Section 7 addresses the construction and start-up phases of the project and has been included because a significant number of documented IAQ cases were a result of activities, which took place during these phases of the project. Not requiring airflow measurement is analogous to ignoring the requirement for 62-201 measuring devices to maintain automatic temperature control.
Of course, provision for permanently mounted airflow measurement devices and controls would awhrae reduce both the cost and time associated with such changes as long as the HVAC load capacity could accommodate future requirements. A base ventilation rate will always be required, regardless of occupancy, to dilute such contaminants. etandard
ASHRAE Standard 62-2001
Other potential contaminants for which definite limits have not been set are discussed in Appendix B. When applied in accordance to manufacturer’s recommendations, airflow measuring devices such as those manufactured by EBTRON, only require the verification of operation by test and balance professionals. The allowable contaminant concentration in the occupied zone can be used with various system models in Appendix [D] to compute the required outdoor air flow rate.
In addition, the section should strongly encourage the use of airflow measuring standagd in critical zones of VAV systems for the continuous calculation and reset of the multi-space equation defined in section 6. As a result, this condition rarely, if ever, exists. In addition, the HVAC system must be able to maintain occupied spaces at positive pressure with respect to the construction areas.
Interpretations for Standard
Outside airflow rates can also be reduced if the critical zones have variable occupancy. Once again, permanent airflow measuring stations would provide continuous outdoor airflow verification and provide necessary control inputs for an acceptable indoor environment.
The statement below merely indicates that human body odor will most likely be acceptable if the conditions above are true.