Dust control ventilation

In addition to the previously noted safety factors associated with these processes, there are additional needs for dust control and ventilation for dissipation of various vapors from pressing, tempering/heat treatment, and machining and finishing operations. 

This discussion will address needs, applications, performance characteristics, and design considerations for LVHV exhaust ventilation. The applications are primarily for dust control. LVHV systems can be effective for protecting workers from dust exposures and for recovering valuable process materials. The equipment, excepting the nozzles, involves technology that is the same as for large central vacuum cleaning systems. 

LVHV nozzles can create problems that may be sufficiently severe as to prevent their use, usually in the form of ergonomic encumbrances and excessive noise. These problems can be dealt with, to limited extents, and LVHV applications can be effective. It must also be understood that dust control by 1..VHV systems is ultimately limited. No ventilation control measure can ensure sufficient worker protection down to extraordinatily low acceptable dust levels. Worker protection must always be confirmed by industrial hygiene monitoring and evaluation, and administrative control measures such as respiratory protection may be necessary. 

If well designed and properly used, LVHV applications have the primary advantage of effective dust control. LVHV systems also require much less replacement airflow than conventional ventilation systems. This can result in significant savings in operating costs to condition the replacement air. These savings can help to offset the typically high installation costs for LVHV systems,... 

Many operations within the laboratory start with weighing. It is difficult to undertake precise weighing in conventional laboratory fume hoods, as the airflow and vibration inside an operating fume hood often disturb the balance. In order to accommodate the need for an engineered control at this scale of operation, dust control systems have evolved known as ventilated weighing safety enclosures or powder weighing hoods. Key characteristics of a ventilated weighing safety enclosure include ... 

Local Exhaust Ventilation—Exhaust ventilation at the source of dust generation is perhaps the most widely used method of dust control. This method of control requires that an air movement be provided at the source sufficient to convey the dust into the hood and duct system... 

Fire and explosion prevention, dust control, proper storage of flammable liquids, grounding of electrical equipment, accessibility of extinguishers and hose lines, leak detection of reaction vessels, adequate ventilation of storage rooms, accumulation of solid wastes, static spark control (metal-free shoes, static bars on friction-generating machinery). 

The improved measures were applied in the fully-mechanized face, the dust removal effect of the working face was observed, as shown in Table 1 Through observation, after the 131419 working face adopted the optimized dust removal system, the efficiency of reducing dust reached 80%, while using the traditional dust removal methods, such as ventilation and dust control, could only reach about 40%, so the optimized dust removal system can better improve the working environment, and it could be more beneficial to the health of workers, and provide guarantees for the safety production of coal mine. 

Dust control. Small plutonium oxide particulates may become airborne and result in inhalation dose. Particulate size distribution at various stages and aerosol transport are subjects for careful study. Equipment and process designs can be used to control airborne particulate, such as setting up various pressure control zones in ventilation design, installing HEPA filtration systems, and installing area airborne particulate monitors. 

A thorough occupational hygiene survey should be conducted and any potential risks eliminated or controlled. Noise, dust, vibration, ventilation, lighting, and similar hygiene risks all impact on employees. The workplace should be free from these hazards. 

Exposure to chemical and physical agents Ventilation and dust control Right-to-know/hazards communication... 

For process equipment, designers need to specify necessary safety features and the tests for meeting requirements. For process equipment, there should be fail-safe features. Fire protection, overpressure, excess heat, runaway reactions, dust control, exhaust ventilation, dangers of flammable liquids, leaks, sensing devices to report status are all examples of important safety features. Designers and purchasers need to consider access for setup, maintenance and cleaning. There may be a need for access by stairs, fixed ladders or platforms as part of large equipment. 

Prevention of contact dermatitis caused by woods is difficult. Dust control with proper ventilation is very important. Protective clothing should be worn and must cover the exposed areas. Only seldom, can a strong sensitising species be substituted by a less sensitising one. 

Mandates the minimum requirements for an elevated safe work platform Mandates engineering controls of physical hazards such as ventilation for dusts, control of noise, and control of ionizing and non-ionizing radiation... 

Dust control includes both external and internal methods. Source ventilation, hood ventilation, and room ventilation are typical external methods. Interned methods include reactor ventilation and the use of a closed charging system, which provides a suction transfer of powder into an evacuated reactor. Dust control equipment should be interlocked with production machinery to assure simultaneous operation and protection. 

Dust control systems usually include hoods and enclosures connected to a local exhaust ventilation system that discharges to cyclone collectors and scrubbers or a baghouse in series. The most common type of control equipment is the baghouse these are increasing in use as more stringent pollution control codes are adopted. These filters provide excellent collection efficiency with little or no visible emissions and the collected dry fines are sometimes usable in concrete mixes. However, if the exhaust gas temperature is at or near the dew point of the gas, condensation of moisture on the fabric filters is always a possibility and poses a serious fire hazard. The other type of the commonly used control equipment is the venturi wet... 

The mandatory standards include requirements specific to mines such as those pertaining to roof support, ventilation, permissible electrical equipment, ground control, hazardous dust control, and other standards that would be pertinent to any heavy industry. The mandatory standards also impose... 

Colinet, J.F., J.J. McClelland, L.A. Erhard, and R.A. Jankowski. 1990. Laboratory evaluation of quartz dust capture of irrigated-filter collection systems for continuous miners. RI 9313. USBM. 14 pp. Colinet, J.F., and R.A. Jankowski. 1997. Dust control considerations for deep-cut faces when using exhaust ventilation and a flooded-bed scrubber. SME Transactions 302 104-111. 

When the mine ventilation, methane, and dust control plan is up for a 6-month review, all coal mines should determine satisfactory locations on the main entries for temporary seal locations. Furthermore,... 

Venting The term venting is popularly associated with pressure relief systems and devices, which are installed on enclosed conveyors (pneumatic, air gravity, screw etc.) and silos to prevent pressure buildup and potential explosions. However, sometimes dust is directly vented to either the atmosphere or to a ducting system with or without dilution with air. In this case venting may be classified as a method for non-fugitive dust control by ventilation or Di-Pution. 

What seems so problematic in retrospect is the degree to which Pyro operators worked in conditions that were so volatile and dangerous that it seems almost ludicrous to talk in terms of reasonable action. The mining company had violated all of the major regulations relating to methane control (a) The volume and velocity of air were not sufficient to exhaust methane [30 CFR 75(301)] (b) no preshift exam was conducted on the day of the explosion [30 CFR 75 (303)] (c) the approved ventilation system and the dust control plan were not being followed (30 CFR 75(316) and (d) changes in the ventilation plan substantially affected the health and safety of miners [30 CFR 75(322)]. 

Dust generated during operation - Ventilation systems can be used or equipment will be designed with dust control filters which minimize the dust produced in the plant. 

Generally, it is more economical to prevent explosive atmospheres ia rooms than to try to provide explosion-proof electrical equipment. Personnel should never be allowed to work ia a ha2ardous atmosphere. Where such an atmosphere cannot be avoided through control of flammable Hquids, gases, and dusts, access to the area iavolved should be limited and the area segregated by hoods or special ventilation. Electrical equipment on open, outdoor stmctures more than 8 m above-ground usually is considered free from exposure to more than temporary, local explosive mixtures near leaks (86). 

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