Blue fire does the same amount of dammage as the regular

1. step on blue fire (difficulty set to hard, no effects, no armor). Look at how much damage it does to you
2. step on regular fire. Look at the damage it does again.

you will see that blue fire and regular fire cost 1hp of damage each time the player hurts (1 sec)

blue fire should cost 2hp (one full hear) each time the player hurts (1 sec)