Can damage over time effects crit?

I've been using a Witch Doctor build that uses Haunt and Locust Swarm, and I've noticed that my damage varies really widely sometimes. Can these spells "crit"? Is that determined on cast or per tick? How can you tell if it crits? Can a non-crit re-cast override a critical existing DoT effect?

How do Crit Chance and Crit Damage affect DoT skills?

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Can you crit damage over time?

If there is no crit chance listed, it cannot crit ever. RF is a dot, damage over time nodes work on it.

What increases crit damage?

Increased Critical Damage Support is a support gem that increases the amount of damage done by critical strikes scored with the linked skill.

How much damage does crit damage do?

Critical Hits refers to the random occurrence of an attack dealing increased damage to an opponent. If the attack is a Critical Hit, the CRIT DMG multiplier is applied: The base CRIT Rate for most characters is usually 5%, while the base CRIT DMG is 50%.

Does damage over time apply to chaos damage over time?

Flat damage from things like Added Chaos Damage Support does not apply to damage over time.

Path of Exile Guide: Damage Over Time (Ignite, Poison, etc)

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