Understanding Sources of Contaminants 对污染物来源的了解

Introduction 简介 Before considering specific measures to control hazardous substances it is important to have a good understanding of the sources of contaminants that require control 在考虑用专业方法来控制有害物质之前，对需要控制的污染物的来源作深刻的了解，这是至关重要的。

Processes & Sources 工艺和污染源 Process – The way airborne contaminants are generated. For example in woodworking the processes could be cutting, routing, planning or sanding 工艺——空气中污染物产生的途径之一。比如，在木材加工过程中，其工艺可能就是切割、开槽、刨削 或砂磨 Source – The point where the contaminant is generated by a process 污染源——在工艺过程中产生污染物的源点

Processes & Sources 工艺和污染源 Guard 防护装置 Boundary layer of dusty air 含尘空气的边界层 Speed and direction of cloud 污染云团的速度 和方向 Contaminant cloud jet 污染云团喷射流 Process 工艺 Contaminant cloud jet 污染云团喷射流 Source 污染源

Types of Sources 污染源类型 Buoyant 浮动的 Hot fumes 高温烟气 Injected into moving air 注入到流动空气中的 Spray painting 喷涂作业 Dispersed into workplace 散落到工作环境中的 Draughts 通风排气 Directional 定向的 Power tools 电动工具

Buoyant 浮动的 Source: University of Wollongong

Injected into Moving air 注入到流动空气中的 (Show HSE spray gun video) Source: University of Wollongong

Dispersed into Workplace 注入到流动空气中的 (Show HSE stacking sacks video) Source: University of Wollongong

Directional 定向的 (Show HSE Receiving Hood video) Source: University of Wollongong

Sub Groups of Directional Sources 定向污染源的分组 Explosive release 爆炸释放 Progressive release 连续释放 Doughnut‑shaped release around a rotating disc 在旋转圆盘周围的环形释放 Broad fan‑shaped release from a rotating disc 在旋转圆盘上的宽扇形释放  Narrow jet release from cutting trench 在开沟作业中产生的细长喷射释放  

Explosive release 爆炸释放   (Source: HSE – reproduced with permission)

Progressive release 连续释放   (Source: HSE – reproduced with permission)

Doughnut‑shaped release around a rotating disc 在旋转圆盘周围的环形释放 (Source: HSE – reproduced with permission)

Broad fan‑shaped release from a rotating disc 在旋转圆盘上的宽扇形释放 (Source: HSE – reproduced with permission)

Narrow jet release from cutting trench 在开沟作业中产生的细长喷射释放 (Source: HSE – reproduced with permission)

Strength of Sources 污染源的强度 When considering the strength of a source it can be defined in terms of the area from which the contaminant originates, the flow of the contaminant away from the source and the atmospheric concentration of the contaminant 污染源的强度可根据污染物产生的场所、从污染源流出的污染物，及环境中污染物的浓度来定义。  

Contaminant Clouds 污染云团 As the contaminant moves away from its source the more dispersed it becomes and thus much larger 随着污染物扩散离开污染源，扩散越大其污染面也积越大 While dilution reduces the contaminant concentration within the atmosphere, it is always more effective to control the contaminant close to its source 如果通过稀释能降低大气中污染物的浓度，一般来说，在接近污染源的地方控制污染物会更有效

Reasons to Control Clouds at Source 从污染源控制污染云团的理由 The volume of contaminant in the atmosphere is smaller and thus easier to control 此时，大气中的污染物体积较小，因而较易控制 Collection of the whole contaminant cloud is more likely 更有可能收集全部污染云团  Operators are less likely to be exposed 操作人员接触污染物的可能性更小

Controlling Hazardous Substances 控制有害物质 Consequently, the approach to controlling a particular hazardous substance is determined to a large degree by a combination of factors including: 因此，控制特定有害物质的方法，在很大程度上由以下各因素决定：

Factors which Determine Control Approach 决定控制方案的因素 Source strength 污染源的强度 Contaminant cloud volume, shape, speed and dissection of movement 污染云团的体积、形状、移动速度和移动过程中的分解  Contaminant concentration 污染物浓度  

Multiple Sources 多种污染源 Notwithstanding these factors, it is important to understand that a single process can create several sources of contaminants at different stages 尽管我们已经知道了上述因素，但更重要的是，要弄明白一种单一的工艺可以在不同阶段产生几种污染源

Multiple Contaminant Clouds 多种污染云团 Guard 防护装置 Boundary layer of dusty air 含尘空气的边界层 Speed and direction of cloud 污染云团的速度 和方向 Contaminant cloud jet 污染云团喷射流 Process 工艺 Contaminant cloud jet 污染云团喷射流 Source 污染源 (Source: HSE – reproduced with permission) 图片来源：HSE——复制已得到许可

Don’t Jump To Quick Decisions 不要快速做出决定 What you think may be present 你所考虑的可能是存在的 What’s actually there 确实存在

Common Processes & Sources 常见工艺和污染源 Rotating tools & parts 旋转工具和部件 Orbital, belt & disc sanders 旋转式 、带式和圆盘式砂磨机 Disc cutter 圆盘式切割机 Lathes 车床 Drills 钻床 Abrasive wheels 砂轮 Hot & cold processes 热加工和冷加工工艺 Furnaces & casting 熔炉和铸造 Soldering, brazing & welding 锡焊、铜焊和电焊 Using liquid nitrogen 使用液态氮

Common Processes & Sources (cont) 常见工艺和污染源（续） Free-falling solids, liquids & powders 自由落下的固体、液态和粉末 Falling liquid, powder & solid material 落下的液体、粉末和固体物质 Conveyor transfer of powders or solids 粉末和固体的传送运输机 Displacement 移送 Liquid, powder and granular solid transfer into a container 传送到容器中的液体、粉末和固体颗粒物质 Spraying & blasting 喷涂和喷砂 Paint spraying & abrasive blasting 喷漆作业和喷砂处理

Common Processes & Sources (cont) 常见工艺和污染源（续） Fracturing solids 碎裂中的固体 Rock crushing 岩石压碎 Impact & vibration 冲击和震动 Dumping dusty sacks on a hard surface 粉尘包倾倒在较硬的地面 Machinery vibration re-suspending dust 机械震动导致粉尘再次悬浮 Compaction 碾压 Waste crushing 废物压碎

Common Processes & Sources (cont) 常见工艺和污染源（续） Handling 处理 Sorting waste 废物分类 Machining 加工 Milling, turning 铣削、 车削 Abrasion 打磨 Sanding, grinding, polishing 砂纸打磨、研磨、抛光 Sweeping 清扫 Dust & particulate matter 粉尘和颗粒物质

Key Point To Remember 需记住的要点 For every process there is a need to investigate & evaluate the significance of every contaminant source before considering which control strategies are appropriate 对每种工艺而言，在考虑哪种策略较合适之前，有必要调查并评估每种污染源的重要性。