A gas grenade is a handheld weapon that delivers a cloud of noxious gas. Depending on the chemical used, the fumes may irritate mucus membranes (e.g. eyes and nose) or skin, or may have more serious effects such as rendering victims unconscious or dead.
Grenades that use toxic chemicals are banned by international law, but may still see illegitimate use.
Modern police and military forces may use non-lethal tear gas to disperse crowds or incapacitate combatants.
— Gadget Description
A Gas Grenade is a tear gas weapon featured in Battlefield Hardline. The caused effects can be nullified with a gas mask. Upon exposure to the gas, players will receive constant damage as well as an effect similar to suppression while within the cloud, allowing it to inevitably kill those who are continuously afflicted. The gas also doubles any damage taken for those affected by it, making it further useful for clearing out enemies, as any stragglers will be much easier to kill.
While the Gas Grenade is an available option for grenades, it is also able to be used as a secondary weapon for Counter Attack Trucks, being shot out in a similar manner to a 40mm Grenade. While providing the same effect, the gas grenade effectively has a much larger range. Due to its suppression effects, the gas grenade is a great tool for crowd control, allowing players to flush enemies from tight places and force engagement.
— In-game description
The Gas Grenade is a gadget featured in Battlefield 1 and was first seen during the Battlefield 1 reveal trailer. It is modeled after the Mk.V CN Gas Grenade.
Upon detonating, a cloud of poison gas that durates for 15 seconds is spread around the point of release. Obscuring vision, inflicting suppression, and depleting health of non-friendlies (at the rate of 15 health per second), it can only be countered with the Gas Mask which is available for all standard infantry kits.
The grenade is effective in area control and will kill enemies who fail to don their gas masks. Due to forcing players to wear masks in order to avoid the gas's lethality, it also has the added benefit of reducing long range combat by those within the gas cloud as the mask does not allow players to aim down sights, favoring weapons that have good hipfire accuracy. Teammates do not take damage, but will still cough and suffer reduced vision. It is not possible to distinguish between gas deployed by friendlies from that of the enemy except by a grenade indicator.
Since the Sentry Kit does not offer the use of a gas mask, gas grenades are a very effective way to take down a Sentry. Cavalry kits offer gas masks but players must first dismount from their horses to equip them. Horses themselves are also vulnerable to gas. Players in tanks are protected while they remain inside (and can equip a gas mask while inside), but occupants of all other vehicles may take damage if not wearing a mask.
Gas Grenades may also be dispensed by other means; launched in shell forms from the St. Chamond's Gas Assault Package, mortar shells fired from Mortar Artillery Trucks or Landships, and emitted by certain vehicles.