Filters ventilation systems

The liquids collected on the bottom of the containment building are transferred by a sump pump (13) in the radioactive discharges tank (14) located in the auxiliary building (15). This building is provided with a filtered ventilation system. 

The basement floor plan for the facility is depicted in Figure 2.4-1. A three zone confinement and filtered ventilation system is used to control migration of radioactive contaminants in the basement processing areas. These zones are defined as follows ... 

To withstand large SG leaks (a postulated rupture of several SG tubes, i.e., a beyond design basis initiating event), the gas system is connected with the passive heat removal system (PHRS) tank. The connection line is blocked by a membrane device designed for rupture under a gas system pressure of 1 MPa that is not dangerous for the reactor mono-block vessel. In the event of membrane rupture, the steam will be condensed in the water of the PHRS tank. In this, the volatile radionuclides of the cover gas remain in the tank water and the radioactive uncondensed gases will be released into the atmosphere via the filtered ventilation system. The radioactivity release will not exceed the permissible levels. 

Ventilation systems with appropriate filtration shall be provided for use in operational states and DBAs. For many research reactors filtered ventilation systems are essential to fulfil the function of confining radioactive material (see paras 6.120-6.130). 

It is a good idea to incinerate filters in well-filtered furnaces in order to burn trapped impurities, reduce quantities of waste, and recover some energy. The filters from normal ventilation systems could also be dumped at a landfill. 

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

Since the pressure generated by most fans is far in excess of pressure differences due to buoyancy and wind, the performance of a powered ventilation system is effectively independent of these, and flow rates and directions can be confidently predicted and will be constant regardless of conditions. The high-pressure generation also allows resistive components such as heater batteries, filters and attenuators to be used within the system. 

This operation is also performed using machines. The cured plates are fed into the parting machine by mechanical means. The plates are parted in the machine and then collected when the operation is completed manually. The parted plates are thereafter stacked for use in battery assembly. More rejects are also generated in this section as well as some lead dust. The ventilation system in this area ensures that the lead dust generated is removed from the work area and discharged into the atmosphere through a baghouse filter. 

Many processes involve open operations (e.g. filters, drum handling, etc.) that create VOC emissions. If this is the case, it is often not practical to enclose all such operations, in which case, a ventilation system needs to draw a continuous flow across the operation into a duct and then a vapor recovery system, before being released to the atmosphere. 

Dilution ventilation Design ventilation systems to control low-level toxics. Design locker rooms with good ventilation and special areas or enclosures for contaminated clothing. Design ventilation to isolate operations from rooms and offices. Design filter press rooms with directional ventilation. 

Other Recirculation of exhaust air from agent areas is prohibited. No connection between agent area and other areas through the ventilation system are permitted. Emergency backup power is necessary. Hoods should be tested semiannually or after modification or maintenance operations. Operations should be performed 20 centimeters inside hoods. Procedures should be developed for disposal of contaminated filters. 

In general I should like to plead for an integration of research on ammonia volatilization and odour research. In many cases odour control can be combined with reduction of ammonia losses. This is for instance the case with storage systems, ventilation systems, bio-filters or air scrubbers and injection of slurry. This double effect gives more possibilities to make the cost of control paying. 

The caravan is equiped with an own propan gas operated electric power unit and the ventilation system is equiped with activated carbon filters to get an odourless athmosphere guaranteed. After arriving at a farm it takes less than five minutes to prepare the system for the first measurement. With a team of four well-trained panelists and three repetitions it takes only about six minutes per sample. Inclusive necessary breaks for the panelists and for changing the sample bags six measurements per hour are possible, but not more than about 20 samples per day. 

The filter unit was located entirely inside the respective buildings and was independent of the ventilation system. The unit consisted of a suction box (usually floor standing) to which the filter material was attached usually as a flat vertical surface of an area to give a face velocity of about 0.75 m/s. Dust collected on this surface and was removed with a vacuum cleaner. Cleaned air was directed into an overhead discharge duct with a permeable lower surface. The capacity of the fan in the filter unit was made the same order as that of the main ventilating fan. The overhead duct was located above and as near to the stock as possible so that the clean air flowed downwards towards the stock. This air did not cause a draught because it was discharged at a low speed (0.3 m/s) and as it was recirculated it was at the same temperature as the air in the room. 

The vent streams from the HD reactors and the TCC Effluent Tank are combined, scrubbed with a sodium hydroxide scrubber, condensed and passed through dedicated carbon filters before entering the site cascade ventilation system. 

The ton container clean-out (TCC) system, neutralizers, and hydrolysate storage sections all produce small amounts of vent gas, totaling about 2.7 lbs/hr. In the cascade ventilation system, these gases are passed through two-stage carbon filters and are then exhausted to the atmosphere. A separate... 

Perform daily assessment of the bedding conditions. While this is a standard procedure in most vivaria, some strains of diabetic mice such as BKS.Cg-w +/+ I.epfdh/] mice need additional attention because of related kidney problems, resulting in polyuria. Even with a HEPA-filtered ventilated caging system, mice caging may need to be changed two to three times weekly as the diabetic condition worsens. 

Local exhaust ventilation systems LEV required at all dust- or vapor-generating operations and exhausted to the outside through HEPA filters. Full enclosure (containment) ventilation systems recommended... 

Ventilation is the standard method of controlling exposure to airborne vapors of epoxy resins and solvents. Ventilation involves controlling air flow to reduce exposure. Local exhaust ventilation systems capture the vapor at the source and either filter or remove it from the work area. The ventilation system needs to be designed so that vapors, aerosol, and dusts are pulled away from, and not into, the breathing zone of the workers. A constant supply of fresh, noncontaminated air should be available at all times. 

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. 

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