Phasmophobia smudge sticks - how to use them

How do you use smudge sticks in Phasmophobia? For anyone that doesn't know, smudge sticks are neatly tied herbs used for healing, or in this case, warding off evil spirits. In real life, they can contain all manner of ingredients from rosemary to garlic and are often wafted through the air once lit to rid the area of a bad aura.
Using smudge sticks in Phasmophobia isn't about healing, though, it's about staying alive and these little garlicky parcels are super handy to cleanse an area of apparitions and buy yourself some more time for hunting. Smudge sticks are used in a lot of objectives and can be purchased from the menu using the in-game currency you've collected from previous missions. You can carry up to four smudge sticks, and will also need a lighter to use them.
Smudge sticks also interact with some of the ghosts in Phasmophobia in different ways: using it on a Spirit will prevent it from attacking and using it on a Yurei will prevent it from moving. Here are the other ways you can use smudge sticks in Phasmophobia.
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