Ventilation requirements

For continuous release of gas or vapour the steady-state dilution ventilation required to reduce the atmospheric pollutant to a level below its hygiene standard is given by... 

AMD 1 Particulate air filters for general ventilation - Requirements, testing, marking (AMD 8367) dated 15 November 1994. Superseded BS 6540 Part 1 1985... 

Since the OELs provide the basis for ventilation requirements, an astute designer tries to find out how secure the OELs of the chemicals which will be used in the plant he or she is planning. Some of the chemicals used may totally lack OELs. Therefore, it is advisable to become familiar with the relevant literature, preferably together with a specialist. It is clear that the ventilation engineer needs to be aware of the possible significance of toxicology for industrial ventilation construction. 

Demand-controlled ventilation (DCV) is one approach to reduce energy consumption due to ventilation, that is gaining popularity in both industrial and nonindustrial applications. It is used in cases where ventilation requirements vary with time, regularly or irregularly. The control is based on a specified level of indoor air quality by means of continuous measurement of the parameters, that are expected to primarily determine the lAQ, such as the concentration of the main contaminant liberated from the production process. The principle is thus similar to the one in some better-known nonindustrial applications, e.g., CO2 levels in rooms with dense human occupancy (theaters, classrooms, etc.) or nicotine concentration in smoking rooms. See also Section 9.6. 

Minimum ventilation requirements The lowest possible airflow rates that will ensure all obnoxious products are removed from the air by the introduction of fresh air. 

AMD 1 Particulate air filters for general ventilation - Requirements, testing, marking (AMD 8367) dated 15 November 1994. Superseded BS 6540 Part 1 1985 Natural gas - Determination of sulfur compounds. Determination of hydrogen sulfide, mercaptan sulfiir, and carbonyl sulfide sulfur by potentiometry. Also BS 3156 Subsection 11.4.3 1994 Natural gas - Determination of sulfur compounds. Lingener combustion method. Also BS 3156 Subsection 11.4.5 1994... 

Consult American Society of Heating, Refrigeration, and Air Conditioning Engineers (ASHRAE)19 ventilation requirements and the National Fire Protection Association (NFPA).20 As a system is designed, consider the use of... 

The amount of ventilation required, like the amount of lighting, depends upon the circumstances. Some general rules are given in Table 8-8.44,45 Note that there are several guidelines and that in some instances more than one may apply. When this occurs the requirements for each should be calculated and the maximum rate used. None of these guidelines applies to hazardous areas, where the air may have to be moved more rapidly. Some estimates are given in Table 8-9. Safety guidelines and OSHA (Occupational Safety and Health Act) rules should be consulted under these conditions. 

In most plants the only areas that are air-conditioned are the offices, laboratories, and control rooms. For offices, 3-6 volt amperes/ft2 (32-65 volt amperes/m2) is a typical load.46 For control rooms the load will be somewhat higher, and for laboratories, because of increased ventilation requirements, it may be much higher. 

The ventilation requirements come from Tables 8-9 and 8- 10. The largest estimate should be used when more than one is obtained. 

Ventilation is the exchange of air between the external atmosphere and the alveoli. It is typically defined as the volume of air entering the alveoli per minute. A complete understanding of ventilation requires the consideration of lung volumes. 

The concentration will range from 460 ppm to 2300 ppm, depending on the value of k. Because the TLV for toluene is 50 ppm, additional ventilation is recommended, or the amount of exposed surface area should be reduced. The amount of ventilation required to reduce the worst-case concentration (2300 ppm) to 50 ppm is... 

For both fire safety, health considerations, and proper functioning of fume hoods the air pressure of laboratory areas must be negative relative to surrounding areas. The only exception to this is for certain biocontainment applications. These applications usually require very specific ventilation requirements which will not be addressed. Also, all laboratory ventilation systems, especially fume hoods, should incorporate low flow warning devices. 

Generally hydrocarbon floors areas are open grated construction when elevated, unless solid floors are provided where there is a need for spill protection or a fire or explosion barrier, otherwise ventilation requirements will prevail. 

Blocker/Pa ra lytic ] WARNING Use restricted to experienced personnel Uses Induce paralysis to facilitate ET intubation (RSI) Action Competitive antagonist of acetylcholine Dose Adults Peds. 0.04-0.1 mg/kg IV Maint 0.01 mg/kg q45-60min (onset w/in 1 min duration 30-60 min) Caution [C/-] Cardiac monitor, BP monitor, intubation supplies and ventilator required Contra Use w/ caution in... 

Fire codes recommended installation procedures also detail specifics on pressure/vacuum venting devices and vent hne flame arresters. For example, codes mandate dilferent ventilation requirements for Class I-A liquids versus Class I-B or I-C liquids. Tank vent piping is generally not manifolded unless required for special purposes such as air pollution control or vapor recovery. As always, local codes must be consulted. 

Repair areas where CNG vehicle conversions and repairs are to be performed should have provisions for either natural or forced ventilation. Current codes describe ventilation requirements only for facilities servicing conventional liquid fuel vehicles however, these codes can be used as a basis to determine the needs of facilities servicing CNG vehicles. 

NFPA 88B—Standard for Repair Garages requires that areas below grade used for repair vehicles have a forced ventilation system capable of continuously removing at least 0.75 cubic feet of air per minute few each square foot (cfm/sq.ft.) of floor space [5.8]. This ventilation requirement helps prevent accumulation of heavier-than-air fuel vapors which could accumulate in below-grade areas. 

The 60-percent design specifies the detailed design basis, primary process steps, process flow diagrams, major equipment components, monitoring requirements, facility requirements (e.g., building layouts, electrical and ventilation requirements), and preliminary operational strategies. Detailed final specifications of all process components, facilities, and operations are not complete. 

Cleaning Less chemical All chemicals contained in modules piping More Chemical Limited to soaking rather than recirculation Covers and ventilation required over cells... 

The polymers used must protect murals from moisture, must be totally inert, and must not alter the appearance of the paint layer or cause structural changes within it. Proper ventilation requirements for polymer use during conservation must also be considered. When new and better techniques become available, it must be possible to remove these polymers and the polymers used in the structural consolidation of the plasters with minimal or no damage to the tomb, in the tradition of reversible conservation treatments. 

Thompkins, R.W., 1982. Radiation in uranium mines (a manual of radon gas emission characteristics and techniques for estimating ventilating requirements). Can. Inst. Min. Metall. Bull., 75 (845) 149-156, (846) 62-67, (847) 98-104. 

The current professional ventilation standard (ASHRAE 62-89) suggests two approaches to ventilation a ventilation rate procedure and an air quality procedure. The former provides a tabular approach to ventilation requirements office buildings require 20 ft of outside air per occupant per minute to maintain occupant complaint rates of environmental discomfort at below 20%. This assumes relatively weak pollution sources. When stronger sources are present, the same rate will provide less satisfaction. For example, when smoking is permitted at usual rates (according to data from the early 1980s), 30% of occupants will complain of environmental discomfort. The second approach requires the selection of a target concentration in air (e.g., particulates, VOCs, and formaldehyde), information on emission rates (pollutant per time per mass or surface), and... 

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