[Ycto]

You can use

Код:

GetPlayerWeapon(playerid)

Use it like

pawn Код:

if(GetPlayerWeapon(playerid) == [Insert Teargas Weapon ID Here])
{
Your code...
}

Sorry, was too lazy to look for the weapon ID myself :P It's on the wiki.

You could also just change

pawn Код:

if(!IsPlayerInAnyVehicle(playerid))
{

with

pawn Код:

if(!IsPlayerInAnyVehicle(playerid) && GetPlayerWeapon(playerid) == [Insert Teargas Weapon ID Here])
{

Don't know that last thing for sure though, didn't really look into your script =)