Chill
Chill is an elemental Status Ailment inherent to Cold that slows the movement, attack, and cast speeds of the affected target by 30%.
Any hit of Cold Damage has the potential to Chill the target. Chill can also be inflicted by skills including 
Ice Shot, 
Arctic Armour, and Module Error: No skills found with q_where = skill.active_skill_name="Arctic Breath", which leave patches of ice on the ground.
When a target is hit with Cold Damage, it is Chilled for a duration proportional to the damage.
Let N be the cold damage dealt and L be the target's maximum life. The base chill duration D in milliseconds is then given by:
If N > L ÷ 3, then N = L ÷ 3 D = N ÷ ( L ÷ 100 ) × 138ms
If the duration would be less than 300 milliseconds, the Chill effect is not applied. The maximum, unmodified chill duration from cold damage is 4.6 seconds.
When playing in a party, a monster's max life is treated as being the same as it would be in a single player game for the purposes of calculating these durations.