What does ASTM C90 specifications certification consist of?

ASTM C90 is a standard specification for load-bearing concrete masonry units. The certification process involves ensuring that the concrete masonry units meet the requirements outlined in the ASTM C90 standard. Here are some key aspects of the certification process:

1. Dimensions and Tolerances: The concrete masonry units must adhere to specified dimensions and tolerances for length, width, height, and squareness.
2. Compressive Strength: The units must possess the required compressive strength, which is determined through testing. This strength is crucial for ensuring the structural integrity of the masonry.
3. Absorption: The units should have controlled levels of absorption to prevent excessive moisture penetration, which could compromise the durability of the masonry.
4. Weight Classification: ASTM C90 categorizes concrete masonry units into different weight classifications based on their density. The certification ensures that the units are classified correctly according to their weight.
5. Sampling and Testing: Concrete masonry units undergo sampling and testing procedures to verify their compliance with the standard. This includes sampling from production batches and conducting various tests such as compressive strength tests and absorption tests.
6. Documentation: Manufacturers are required to maintain documentation demonstrating compliance with ASTM C90 specifications. This documentation may include test reports, quality control records, and other relevant information.

Overall, ASTM C90 certification ensures that concrete masonry units meet the necessary quality and performance standards for use in load-bearing applications, providing assurance to builders, engineers, and regulatory authorities regarding the reliability of the masonry units.