Beherit Red vs Orange Fire

How close are they?

ΔE 17.8, loose: different enough that you should pick on purpose. Orange Fire is a little lighter, warmer than Beherit Red.

Can I use Orange Fire instead of Beherit Red?

Not as a straight swap; see the closer alternatives below. Loose match (ΔE 18). Orange Fire is a little lighter, warmer than Beherit Red.

Can I use Beherit Red instead of Orange Fire?

The same difference applies the other way round: Beherit Red is a little darker, cooler.

ΔE is the colour difference between our two swatch estimates: under about 6 is close, over about 15 is loose. Real paints also differ in finish, coverage and how they thin, so test before you commit.