Can P6KE6.8A be used for ESD protection in addition to surge protection?

Yes. While the P6KE6.8A is primarily designed and rated for surge protection per IEC 61000-4-5 (lightning surge), its sub-nanosecond response time also makes it effective for ESD protection per IEC 61000-4-2 (±15kV air discharge, ±8kV contact discharge). This dual capability is particularly valuable in industrial and telecom applications where both surge and ESD threats are present on the same power input lines.