Cryogenic chamber

From The Stargate Omnipedia

Cryogenicchamber2.jpg

Technology capable of cryogenically freezing a subject body, decreasing the rate of cellular decay to a near dead-stop. This technology is used by the Tok'ra, and has been used by at least one Goa'uld faction group under the control of Hathor.

The cryogenic chamber is apparently not safe for symbiotes that have not blended with the host, as they are unable to survive the rapid freezing process.

KEY EPISODES

Out of Mind - Hathor uses cryogenic chamber technology on O'Neill, Carter and Jackson, convincing them that they've woken up at the S.G.C. after nearly 80 years of suspended animation.
Into the Fire - A Tok'ra operative puts O'Neill into cryogenic suspension when he is infested by a Goa'uld, killing the symbiote before it blends with him.
Summit - Ren Al tells Major Carter that the Tok'ra kept Martouf/Lantash in stasis for several months after he was shot, in the hopes that they could find a way to save him. Ultimately, they took him out and saved his symbiote.
Fragile Balance - His body dying from a genetic defect, the young O'Neill clone is offered cryogenic freezing by the Tok'ra until a way to save him can be found. He refuses.