Environmental Awareness - Pollution, Resources and Sustainable Practice
This domain tests environmental literacy for the workplace and everyday life: types and sources of pollution, waste management, energy and water conservation, biodiversity, climate change, and sustainable work practice.
Core concepts
- Pollution types: air (particulates, SO₂, NOₓ, CO), water (sewage, industrial effluent), soil (chemicals, plastic), noise (above permissible limits), and e-waste (discarded electronics, which contain lead and mercury).
- 3Rs: reduce, reuse, recycle - in that order of priority.
- Renewable sources: solar, wind, small hydro, biogas, biomass. Non-renewable: coal, petroleum, natural gas.
- Climate change is driven by greenhouse gases such as CO₂, methane and nitrous oxide trapping heat; it is distinct from ozone-layer depletion, which is caused mainly by CFCs.
- Sustainable development meets present needs without compromising the ability of future generations to meet theirs.
- E-waste and used oil must go to authorised recyclers, never to ordinary bins or drains.
Worked example
A workshop replaces ten 40 W fluorescent tubes with 20 W LEDs, used 8 hours a day for 300 days. Find the annual units saved.
- Saving per tube = 40 − 20 = 20 W; for ten tubes = 200 W = 0.2 kW.
- Annual hours = 8 × 300 = 2,400 h.
- Energy saved = 0.2 × 2,400 = 480 kWh (units). Reasoning shown: convert watts to kilowatts, multiply by hours to get kWh, then state the result with the correct unit - a missing unit conversion is the usual error.
Traps that cost marks
- Blaming ozone depletion entirely on CO₂.
- Listing “recycle” before “reduce”.
- Treating e-waste as ordinary dry waste.
- Confusing biodegradable with harmless.
- Giving a benefit of a tree plantation without a measurable indicator.