What trade-offs exist between asphalt emulsions and hot mix asphalt systems?

Asphalt emulsions reduce energy use and safety risk because they can be produced and applied at lower temperatures, lowering fumes and fire hazards and enabling cold processes like recycling. The trade-off is curing dependence on water evaporation and breaking behavior, which makes performance more sensitive to temperature, humidity, wind, and surface moisture. Emulsions can be slower to gain early strength, can wash off if rain hits before break and cure, and require careful selection of setting speed and charge. Hot mix delivers faster strength and predictable compaction but at higher energy, emissions, and handling risk.