set off vs spark off

set off and spark off both are verbs.

Word	Noun	Adjective	Verb	Adverb
set off	No	No	Yes	No
spark off	No	No	Yes	No

As verbs, set off and spark off are synonyms defined as:

Other synonyms of set off include activate, actuate, spark, touch off, trigger, trigger off, trip.

set off (verb)	spark off (verb)
cause to burst with a violent release of energy	put in motion or move to act
set in motion or cause to begin
direct attention to, as if by means of contrast
provoke or stir up
put in motion or move to act
depart for someplace
make up for