To maintain LEED certification and meet compliance requirements, the best approach is to review the applicable LEED standards and align the cleaning policy with them. The correct process includes:

Identifying LEED-compliant equipment and supplies for janitorial services.

Ensuring cleaning chemicals, tools, and processes adhere to LEED sustainability guidelines.

Developing a policy and procedure document based on these standards.

Why the other options are incorrect:

(A) Consulting other professionals is useful but does not ensure compliance.

(B) Professional journals provide insights but may not specifically align with LEED certification.

(D) Vendors can provide input, but they may have biased recommendations based on their product offerings​.