Final answer:
The statement regarding manual shut-off valves being certified and not subjected to conditions outside their certified range is true. Understanding gas behavior under different temperatures and pressures will be covered in grade 11 through gas laws.
Step-by-step explanation:
The statement 'A manual shut-off valve shall be certified to CSA 3.11, CSA 3.16, or CSA 9.1, or approved for use with gas, and it shall not be subjected to either a temperature or a pressure outside of its certified range.' is true. Gas shut-off valves must adhere to specific standards (such as CSA 3.11, CSA 3.16, or CSA 9.1) to ensure they operate safely under the conditions for which they are designed. These certifications ensure the valve can handle standard temperature and pressure conditions it may encounter. In high school, particularly in grade 11, you will learn more about the behavior of gases under various conditions explained by gas laws.