Forced ventilation

In most situations, adequate, usuaHy forced, ventilation is necessary to prevent excessive exposure. Persons who drink alcohol excessively or have Hver, kidney, or heart diseases should be excluded from any exposure to carbon tetrachloride. AH individuals regularly exposed to carbon tetrachloride should receive periodic examinations by a physician acquainted with the occupational hazard involved. These examinations should include special attention to the kidneys and the Hver. There is no known specific antidote for carbon tetrachloride poisoning. Treatment is symptomatic and supportive. Alcohol, oHs, fats, and epinephrine should not be given to any person who has been exposed to carbon tetrachloride. FoHowing exposure, the individual should be kept under observation long enough to permit the physician to determine whether Hver or kidney injury has occurred. Artificial dialysis may be necessary in cases of severe renal faHure. 

Separate forced ventilation is required for some apphcations (for example, adjustable-speed drives which operate at low speed) these must depend on an external ventilation. This classification includes open externally ventilated machines, open pipe-ventilated machines. 

Fire or explosion hazards require special motor enclosures. Hazards include combustible gases and vapors such as gasoline dust such as coal, flour, or metals that can explode when suspended in air and fibers such as textile lint. The land of motor enclosure used depends on the type of hazard, the type and size of motor, and the probability of a hazardous condition occurring. Some available enclosures are explosionproof motors, which can withstand an internal explosion force-ventilated motors cooled with air from a safe location and totallv enclosed motors cooled bv air-to-water heat exchangers and pressurized with safe air, instrument air, or inert gas,... 

In cooling by means of forced ventilation, or where the machine has water-cooled air or gas coolers, the temperature of the air or gas, where it enters the motor must be considered as the cooling air or gas temperature. For motors fitted with heat exchangers the temperature reading of incoming air or gas or water should also be tiikcn. 

Drip- proof Force Ventilated Totally-Enclosed Inert Gas or Air Filled ... 

The force-ventilated type is preferred when a Division 1 classification is necessary. The standard drip-proof enclosure is preferred in Division 2 or in safe locations. For an outdoor installation, serious consideration should be given to using NEMA Type 2 weather-protected enclosures rather than the completely enclosed types. 

Force-ventilated motors, 276 Fouling, 484 Fouling, axial, 246 Foundations, 470-71... 

Handle only in well-ventilated areas, preferable with a hood equipped with forced ventilation. 

The zone model has the following basic limitations 1) complex enclosure geometries cannot be addres.sed, 2) forced ventilation cannot be realistically modeled using simple unit models, 7 ) burning other combustibles remote from the initiating source are not modeled, and 4) siipprcssion activities are not included. 

FIRE SIMULATOR predicts the effects of fire growth in a 1-room, 2-vent compartment with sprinkler and detector. It predicts temperature and smoke properties (Oj/CO/COj concentrations and optical densities), heat transfer through room walls and ceilings, sprinkler/heat and smoke detector activation time, heating history of sprinkler/heat detector links, smoke detector response, sprinkler activation, ceiling jet temperature and velocity history (at specified radius from the flre i, sprinkler suppression rate of fire, time to flashover, post-flashover burning rates and duration, doors and windows which open and close, forced ventilation, post-flashover ventilation-limited combustion, lower flammability limit, smoke emissivity, and generation rates of CO/CO, pro iri i post-flashover. 

In recent years, many closed buildings have again been built in order to meet new noise regulations. The buildings are usually provided with forced ventilation, but this is much less effective than natural ventilation and is usually designed for the comfort of the operators rather than the dispersion of leaks. 

The amount of solvent that can be taken into a vessel for dye-penetrant testing or other purposes should be limited so that evaporation of the complete amount will not bring the concentration above the safe concentration, for example, the threshold limit value, making allowance for the air flow if the vessel is force-ventilated. 

Pressure drop is a concern wherever filters and, to a lesser extent, air cleaners are employed in the path of normal forced ventilation system. 

An open pipe-ventilated machine is an open machine except that openings for the admission of the ventilating air are so arranged that inlet ducts or pipes can be connected to them. Open pipe-ventilated machines shall be self-ventilated (air circulated by means integral with the machine (ICll) or forced-ventilated (air circulated by means external to and not a part of the machine) (IC17). Enclosures shall be as defined in 1.25.1a to 1.25.5a, inclusive. 

Protective. Options are open (no protection), open drip-proof, splash-proof, totally-enclosed, forced-ventilated, self-ventilated, and sanitary. 

A2 Ventilation, e.g., use of airtight manhole lids or forced ventilation... 

Forced ventilation to limit hazardous gas concentrations in the event of a spill or release (the electrical area classification of the area may be contingent on the use of forced ventilation)... 

Cox, G., and Kumar, S. 1987. Field Modeling of Fire in Forced-Ventilation Enclosures. Combustion Science and Technology, Volume 52. 

The gas chromatograph has an oven with sufficient volume to hold the column easily and which can be heated to the desired temperature (between 40 and 450 °C, stabilised to within 0.1 °C). The atmosphere inside the oven, which usually has a very small thermal inertia, is constantly agitated by forced ventilation. Using a cryogenic valve through which nitrogen or carbon dioxide can be introduced, the oven can be regulated at low temperatures. 

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. 

NFPA 88B removes potential sources of ignition from areas where fuels may accumulate by requiring suspended unit heaters to be located at least 8 ft above the floor [5.9]. In addition, other heaters with glowing elements must be located at least 18 in. above the floor, and the garage must have continuous forced ventilation at the rate of 0.75 cfm/sq.ft. [5.10]. 

As far as I know, no documents exist concerning the installation of a ventilation system into this morgue, though it appears inconceivable to operate a morgue without windows, exterior doors, and any kind of forced ventilation. 

Gas Leakage. By forced ventilation, maintain concentration of gas below the range of explosive mixture. Move the tank or cylinder to an open area. Leave to bleed off in the... 

Foote, K., Pagni, P., and Alvarez, N., In temperature correlations for forced ventilation compartment fires, First International Symposium on Fire Safety Science, Gaithersburg, MD, Hemisphere Publishing Corporation New York, 1986, pp. 139-148. 

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