Across
- 4. : chemical oxygen demand, another measure of pollution
- 6. : a device that removes impurities
- 9. : a document that gives instructions for using equipment
- 11. : thick waste material from water treatment
- 12. : tools and machines used for a particular purpose
- 14. : a long tube through which liquids or gases flow
- 16. : the force of water inside a pipe
- 18. : a point where electricity or water leaves a system
- 20. : a device for turning electricity on or off
- 21. : a measure of acidity or alkalinity
- 22. : the cloudiness of a liquid caused by particles
- 26. : when water exceeds the container’s capacity
- 27. : device used to control the flow of liquid
- 28. : a person who runs or controls a machine
- 29. : electrical connections in a building or system
Down
- 1. : an obstruction that prevents flow
- 2. : regular work to keep equipment in good condition
- 3. : a device that detects changes such as pressure or temperature
- 5. : a pipe that removes wastewater
- 7. : a safety device that protects electrical circuits
- 8. : the process of cleaning wastewater
- 10. : an unwanted escape of water or gas
- 13. : a large container for storing liquid
- 15. : checking something carefully for faults
- 17. : a machine that moves liquids from one place to another
- 19. : biological oxygen demand, a measure of organic pollution
- 20. : a small portion of material taken for testing
- 23. : to fix or restore something that is broken
- 24. : a complete electrical path
- 25. : an underground system that carries waste