Hotspot means a life cycle stage whose contribution to an impact category exceeds even distribution across all stages, or all stages collectively contributing more than fifty percent to any impact category. In vehicle LCA guidelines for Global Warming Potential, hotspots refer only to the production phase and are related to parts or components representing minimum twenty percent of Global Warming Potential of the production phase. Level three requires company-specific data for at least one hotspot material or component, with primary data preferred and secondary data traceable and based on field survey data when primary data unavailable.

OICA comments on SG4 Use Phase inputs to GRPE/2025/17 concern vehicle service life definitions, discrepancy and deterioration factors for real-world energy consumption, battery state-of-health degradation for off-vehicle charging hybrid electric vehicles, hydrogen and methane leakage quantification, refrigerant emissions from air conditioning systems, and maintenance parts replacement methodologies. OICA advocates for regional flexibility in service life determination, OEM-specific data for discrepancy factors at Level 4, standardized approaches for battery and fuel cell deterioration, and structured hierarchies for assessing maintenance part replacements over vehicle operational lifetime.