Plenum A pressure equalizing chamber。

Pressure, static Potential pressure exerted in all directions by a fluid at rest。

For a fluid in motion, it is measured in a direction normal to the direction of flow。 Usually expressed in inches water gauge when dealing with air。 (The tendency to either burst or collapse the pipe。)

Pressure, total The algebraic sum of the velocity pressure and the static

pressure (with due regard to sign)。

Replacement air Ventilation term used to indicate the volume of controlled

outdoor air supplied to a building to replace air being exhausted。

Slot velocity Linear flow rate of contaminated air through a slot。 Usually

measured in meters per second (m/s) [feet per minute (fpm)]。

Smoke An air suspension (aerosol) of particles, usually not solid, often originating in a solid nucleus, formed from combustion or sublimation。

Threshold limit values Values, established by ACGIH, for airborne toxic materials (TLV) are used as guides in the control of health hazards and

represent time-weighted concentrations to which nearly all workers may be exposed 8 hours per day over extended periods of time without adverse effects。

Transport (conveying)) Minimum air velocity required to move the particulates in the air stream, measured in m/s (fpm)。

Vapor The gaseous form of substances which are normally in the solid or liquid state and which can be changed to these states either by increasing the pressure or decreasing the temperature。

Work piece Equipment or machinery that, while operating, generates a

fume, gas, vapor, or particulate hazardous to the health of the operator。 Parts washers, wood saws, and degrease units are work pieces。

木材加工车间

7-1 作用  木材工厂在规模和作用方面各有不同。使用在本章中的设计标准作为一个通用的指导方针做为木材商店通风系统的构建。

7-2 操作注意事项 合理设计的通风系统能够有效控制厂房内的粉尘。人体长期接触木屑粉尘可能导致健康问题，并且木屑的增多会埋下火灾隐患，甚至引起爆炸。即使安装了通风系统，以收集大部分灰尘，在每个机器和整个车间的手动清洗仍然是必要的。限制木工排气系统只处理木尘。不要将任何可能产生火花、火焰或热的材料连接到木工排气系统上。

7-3 楼层平面布置  与车间人员进行沟通，以得到他们工作流程和专用仪器的操作数据，以此来设计通风系统以完善设备布局和最小化客房管理。

7-4 设计标准  按照统一设市标准中第4章使用的NFPA 664技术要求大纲来设计设施。

7-4。1排气系统  在系统各功能全负荷运行(例如地板清扫）的基础上计算其系统容量。参考第十章人工ACGIH IV ,测定木材店专用设备排气等级。

7-4。1。1系统布置  系统的布置要满足车间需求。机器要以最大的罩阻力布置，并尽量布置在靠近风扇的地方。大多数情况下，管道系统都是沿着天花及墙壁布置，但是在可拆卸格栅面板下运行管道系统能够更有效减少管道长度，同时在设备周围流出更多工作空间。气力输送系统用于处理可燃固体颗粒，664提供了穿墙和缝隙的相关信息。