What is required if a sleeve is used in plumbing installations?

The correct answer is that if a sleeve is used in plumbing installations, it must be of material approved for water service pipe. This requirement is essential because sleeves are commonly used to protect water service lines as they pass through concrete or other structural materials. The sleeve prevents physical damage to the pipes from external forces and is also designed to prevent any moisture or soil contamination from affecting the water supply.

Using a material approved specifically for water service pipe ensures that it is safe for conveying potable water and meets the necessary standards for durability and reliability in plumbing systems. This adherence to approved materials is critical for maintaining the integrity and safety of the plumbing installation.

Other materials, such as those approved for drainage, gas service, or waste pipe applications, are not suitable for water service due to differing standards and potential contaminants. Each category of material has specific properties and regulatory approvals that make them appropriate for their intended uses, and water service applications require materials that are particularly resistant to corrosion and degradation that could occur when exposed to water over time.