What are the practical differences between mesh and foam seats on ergonomic chairs?

Mesh vs. foam seat at OfficeFurniture2go.com follows climate and user preferences. Standard air-conditioned North American offices: 1.8–2.0 lb/cu.ft high-density foam. Warm environments or users who run warm: mesh seat specifications with appropriate weight-zone tension. High-performance mesh (Herman Miller 8Z Pellicle) performs comparably to properly specified foam. Call 1-800-460-0858.