First, there is no sure fire answer. However, the factors will be determined by how frequently it's used, how long it's left on, and the level of intensity that's desired.
The factors that will determine that will be: how much is used at once, the desired level of intensity, and the length of time that is used.
The size of a quarter is suggested.
That's determined by the amount used, the level of intensity when in use, and the length of time it's used. BUT NEVER LET THE OIL TURN DARK BROWN OR BECOME GUMMY!
We sell them for half the price of major retailers, such as Lowe's and Home Depot.
98% of our bulbs used are 35 watts (with a 50 watt max) the other 2% percent are LED and Chandelier.
No...it's secondary function serves as a night light.
You maybe immune to the scent, ask someone else if they can smell it. (Preferably someone who doesn't have the same exposure to the scent).