Yes, existing buildings can earn LEED points through the LEED for Existing Buildings rating system, which includes air quality testing requirements for ongoing performance verification. Testing demonstrates that buildings continue to meet high indoor environmental quality standards and protect occupant health over time. Benefits include enhanced tenant satisfaction, improved marketability, potential insurance benefits, and demonstration of corporate sustainability commitments. Professional testing provides the documentation needed to maintain LEED certification while ensuring that buildings continue to provide healthy indoor environments for occupants.