Lesson Notes By Weeks and Term v4 - SHS 3
Safety, Quality and the Environment
Download the Lessonotes Mobile Ghana app for faster lesson access on Android and iPhone.
Safety, Quality and the Environment
Download the Lessonotes Mobile Ghana app for faster lesson access on Android and iPhone.
Subject: Manufacturing Engineering
Class: SHS 3
Term: 2nd Term
Week: 7
Grade code: 2.3.3.LI.2
Strand code: 3
Sub-strand code: 3
Content standard code: 2.3.3.CS.1
Indicator code: 2.3.3.LI.2
Theme: Manufacturing Tools, Equipment and Processes
Subtheme: Safety, Quality and the Environment
This page supports the lesson note with a companion video and a short classroom-ready summary.
For class groups and homework, share this lesson page so learners also get the summary, objectives, and full lesson context.
Welcome, students. Today, we are exploring a very important topic that affects every single one of us. Think about the phone in your pocket, the plastic chair you are sitting on, or even the sachet of water you drink. Every single one of these items was made in a factory. This process, called manufacturing, is vital for our country's development, creating jobs and products we need. However, it comes with a responsibility. The way we manufacture can either harm or help our precious environment – our air, our water, and our land. In this lesson, we will become environmental detectives, analysing how factories impact our Ghanaian environment and what can be done about it.
A. Introduction: What is Environmental Impact? In manufacturing, "environmental impact" refers to any change to the environment, whether harmful or beneficial, that happens as a result of a company's activities. This includes everything from extracting raw materials (like bauxite or timber) to processing them, to managing the waste created. We can categorise these impacts into several key areas. B. The Negative Effects of Manufacturing Activities Waste Disposal and Pollution Manufacturing processes create by-products and leftover materials called waste. If not managed properly, this waste becomes pollution. Solid Waste: This includes packaging materials, metal scraps, plastic off-cuts, and sawdust. When dumped improperly or sent to overflowing landfills like the Kpone Landfill Site, it can: Take up valuable land space. Release harmful chemicals into the soil and groundwater (a process called leaching). Choke our gutters and drainage systems, leading to flooding in cities like Accra. *Ghanaian Example:* The widespread plastic waste from sachet water and food packaging is a direct result of manufacturing and poor post-consumer waste management. Liquid Waste (Effluents): This is wastewater from factories. It can contain dangerous chemicals, dyes, and heavy metals. When released directly into rivers and lagoons, it kills aquatic life (fish, plants). It contaminates water sources used for drinking, cooking, and farming by communities downstream. *Ghanaian Example:* The Korle Lagoon has been heavily polluted for decades by industrial effluents and sewage, turning it toxic and unable to support fish life. Textile factories releasing untreated dyes are a major contributor. Gaseous Waste (Emissions): This is smoke and gases released from factory chimneys and generators. It causes air pollution, leading to respiratory problems like asthma. It can contribute to acid rain, which damages crops and buildings. It releases greenhouse gases (like Carbon Dioxide, CO₂) that trap heat in the atmosphere, leading to climate change. *Ghanaian Example:* The industrial area of Tema is known for its factories. The visible smoke from some of these factories, like the Tema Oil Refinery (TOR) or cement plants, directly impacts local air quality. Power Consumption All factories need large amounts of electricity to run machinery. How we generate this power has a huge environmental impact. In Ghana, our power comes mainly from two sources: Hydroelectric (Akosombo and Bui Dams) and Thermal (plants that burn fossil fuels like natural gas or oil). Impact of Hydroelectric Power: While considered "cleaner," building a large dam like Akosombo flooded vast areas of land, displacing communities and changing the river's ecosystem forever. Impact of Thermal Power: Burning fossil fuels releases massive amounts of CO₂ and other pollutants into the atmosphere, directly contributing to air pollution and climate change. The Link: The more products a factory makes, the more power it consumes. If that power comes from a thermal plant, the factory is indirectly responsible for significant air pollution. Destruction of the Environment (Resource Depletion & Habitat Loss) Manufacturing starts with raw materials, which must be taken from the earth. Resource Depletion: This means using up natural resources faster than they can be replaced. Deforestation: Cutting down forests for timber (for furniture manufacturing) or to clear land for a factory. This destroys the homes (habitats) of animals and contributes to soil erosion. Example: The depletion of valuable hardwoods like Odum and Sapele in Ghana's forests. Mining: Extracting minerals like gold, bauxite, and manganese. This often involves large-scale excavation, which scars the land. The processes can also release harmful chemicals like cyanide and mercury into rivers. The activities of 'galamsey' (illegal small-scale mining) are an extreme and devastating example of this environmental destruction. C. The Positive Effects and Mitigation Strategies
It's not all negative! Responsible manufacturing can also have positive environmental effects. Recycling and Upcycling: Some companies are built on turning waste into valuable products. *Ghanaian Example:* Companies like Nelplast Ghana Ltd. collect plastic waste and turn it into pavement blocks and roof tiles. This cleans the environment, creates jobs, and provides useful products. Increased Efficiency: Modern manufacturing aims to be more efficient, using less energy, water, and raw materials to produce the same goods. This is good for the environment AND saves the company money. Corporate Social Responsibility (CSR): Many large companies run environmental programmes as part of their CSR. This can include tree-planting exercises or funding community clean-up campaigns. Sustainable Sourcing: Choosing raw materials that are harvested responsibly (e.g., using wood from a certified, managed forest instead of from an illegally logged area).
Guided Practice (With Solutions)
Instructions: Let's work through these scenarios together as a class.