Here is the full list of all 35 Insurgency: Sandstorm achievements. It takes around 20-25 hours to unlock all of the achievements on Windows.
Complete the tutorial mission.
Destroy an enemy vehicle with a mine.
Destroy an enemy air support vehicle.
Kill an enemy with a vehicle.
Kill an enemy while vaulting.
Navigate through chemical gas while wearing a gas mask.
Call in fire support ten times as an Observer.
Kill an enemy using the mounted weapon on a vehicle.
Capture 100 objectives.
As a Commander, kill an enemy using fire support.
Kill an enemy while blinded by a flashbang
Kill an enemy by burning them.
Kill an enemy by bashing in a door.
Destroy an enemy weapon cache using a remote explosive charge.
Kill three or more enemies with a single grenade or explosive.
Kill an enemy after blinding them with a flashbang
Block an objective from being captured and then clear it.
Kill 3 enemies with a headshot in a row.
Kill an enemy with the last bullet of your magazine.
Kill an enemy right after performing a speed reload.
Capture an objective as the last member of the team alive.
Successfully rig and destroy an enemy weapon cache.
Get the first kill in a round.
Purchase your first item in the Appearance menu.
Win a match of Checkpoint.
Kill an enemy by shooting through something.
Kill an enemy without using weapon sights.
Kill an enemy while they are reloading.
Kill an enemy with an enemy's live grenade.
Kill an enemy with a knife.
Drive a vehicle full of teammates for more than 15 seconds.
Kill an enemy driver with the mounted weapon of their vehicle.
Win a match of Firefight.
Win a match of Push.
Be the Most Valuable Player of a round.