Ventilation extract system

These include, for example, smoke extraction systems. In ventilation and air conditioning systems certain equipment can also require special safety measures (e.g., due to explosion risks). 

VOCs are released during chemical cleaning of bonding surfaces. The extract system is designed on the basis of the steady-state concentration determined for maximum source strength and considering the mechanical extract ventilation only and no air-exchange with the assembly hail. Ehis concentration must be kept below the threshold concentration (TVL) which is set to 300 mg/kg in this example. 

FIOURE M.43 The fectory buMdmg with the two haJmechanical extract system. 

Industrial ventilation A term used to cover any ventilation system designed to remove contaminants. Its use is sometimes restricted to local extract systems. Infiltration Movement of air through a space with no specific ventilation openings by natural forces. 

It is generally only practical to ventilate office spaces by means of a ducted system. If sufficient opening window area is available, either an inlet or extract system alone may be satisfactory, but if optimum control of conditions is required, then both mechanical inlet and extract should be provided. 

Our initial studies on the metabolic pathway of captan in spinach point to similarities with dichlo-fluanid metabolism in strawberries. Preplanting treatment of soil with I C-captan followed by spinach cultivation for 34 days in a closed controlled ventilated cultivating system resulted in a recovery of 87% radiocarbon (Table III). The ma or amount (49%) was found in the soil, 19% in the spinach and 19% as carbon dioxide. Bligh-Dyer extraction of the spinach gave 7.4% of the l c-iabel in the chloroform and metha-... 

Examples of local exhaust ventilation system are drawdown exhaust tables, slot hoods, dust extraction systems, and portable vapor and dust collectors. Care must be taken that the ventilation systems are utilized and maintained as designed. The condition of the filters and air flow rate should be checked periodically as well as the condition of the duct work, motors, belts, etc. 

MD purchased these samples. Formaldehyde release was measured in a dynamic (ventilated) chamber system with one air change per hour as described (17). Air temperature and humidity were controlled. Formaldehyde was trapped using a midget impinger train (H). Samples displaced less than 12% of the chamber air (n). Aqueous formaldehyde and total extracted formaldehyde were measured as described (1, 8, 15-18). 

Small amounts of styrene monomer may be released during processing so the work-place should be adequately ventilated with a fume extraction system over the injection molding... 

To isolate operators from the chemical and prevent irritation of the respiratory tract and the eyes, all work using epoxy products should be carried out in an enclosed environment but, in practice, this is difficult to achieve, particularly with the materials used in the manufacture of composite components. For this reason, ventilation of the work area (through forced extraction systems) and adequate personal protective equipment for workers (gloves, goggles, overalls, facemasks, etc.) are indispensable. 

When mechanical smoke extraction systems are utilised within a building the effect of fire growth is notably less. The smoke laden air containing particles of fuel and substantial quantities of heat is removed from the atmosphere by the extraction system reducing the speed at which a fire grows, while assisting smoke ventilation and allowing persons clear, smoke-free, escape routes. 

Proprietary safety containers (such as dash pots used in the printing industry) should be fitted with self-closing lids for flammable liquids Flammable liquids should not be dispensed or decanted within a store or adjacent to a store. Arrangements for such operations should include the provision of ventilation and extraction systems The storage facility should be located away from ignition sources... 

Any electrical system used as part of the ventilation or extraction systems must meet rigid electrical standards and as in the case of all such equipment be intrinsically safe. As discussed earlier, classifying hazardous or potentially explosive atmospheres is not only a legal requirement under DSEAR but has been widely used to determine the extent of hazardous zones created by flammable concentrations of vapours. 

The extract system from a fumecupboard or other ventilated enclosure has to be carefully designed. Among the particular points to be considered are ... 

Obtain approval to have systems shut down which might be damaged by your testing activities. For example, computer systems may crash when supplies are switched off. Ventilation and fume-extraction systems will stop working when you disconnect the supplies. 

TMS Air Filtration Systems Limited Specialist in air filtration, extraction and ventilation systems. http //www.westmids.co.uk/tmsairfiltration... 

In this method of ventilation, powered extract and input systems are provided. The ratio of the supply to extract will control the pressure produced within the space. 

In displacement ventilation systems air is supplied to the room at low velocity, with a volume flow rate near the floor, and is extracted near the ceiling. The temperature of the supplied air is slightly lower than that of the room. Air is heated by the objects in the room, e.g., computer terminals and photocopying machines, and it rises due to buoyancy. 

Air type Classification of air at a specific point in its passage through an air conditioning or ventilation system, either in the duct or the space, e.g., outdoor air, supply air, treated air, recirculated air, extract air, etc. 

Demand-controlled ventilation (DCV) A ventilation system in which the room airflow rate is governed by an automatic control that depends on the level of a given pollutant within the space. A typical example is allowing the COt in a space to reach a certain level before the extract fans come into operation. However, in many industrial environments other pollutants control fan operation. 

Local extract is used to remove contaminants directly from a process to the exterior without passing through personnel breathing zones. It thus provides a high degree of safety and because small volumes of air are extracted relative to a dilution ventilation system it is energy efficient. 

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