In general 0.0 spawns are easier to tank than mission spawns because a belt spawn has fewer rats so you need to tank much less dps. Characters with as little as 3 million skill points in combat skills can successfully rat for 0.0 rats and not lose any ships while at it. Most players prefer ratting in Caldari battlecruisers and battleships, such as Ravens and Drakes, due to superior tanking ability and ability to deal all four kinds of damage. However, you can use cruisers, assault frigates, and even interceptors for 0.0 ratting. Which ships would handle local rats best depends on local rats. For example, one can successfully use an armor tanked cruiser such as Thorax to rat for Sanshas and Blood Raiders. However this same cruiser will not do so well ratting for Guristas. This is because Sanshas and Blood raiders do a lot of EM damage to which armor has highest resistance. Guristas do a lot of kinetic damage which is more difficult to tank with armor. Rats also differ in the kinds of electronic warfare that they do and the portion of their damage comes from missiles as opposed to turrets. Try out different setups and continue tweaking them to your skills and you will eventually find what works best for you.
There are several approaches to keeping your ship safe while ratting:
1) Keep an eye on local and take note if anyone new enters system. Keep your ship scanner open and do frequent 360 degree scans of the area to see if you can pick up any interceptors or pvp ships on scan.
2) If possible arm for long range combat and keep away from the center of the belt. Warp to 50km rather than 0m. This will place you 50km away from any potential tackler warping into same belt and give you more time to make it out.
3) Create a safespot very close to a planet in system. After you warp into the belt, double click next to the planet to align to it. This will align you very closely to warp to your safespot in case you get jumped.
4) After you have warped to your bookmark continue warping between different safespots and watch out for scan probes. You can also mount a cloaking device and simply cloak up and go afk until the danger passes.
5) Rat with PVP fit. Those looking for ratters in belts often fit to do the type of damage that local rats do not do, counting on it being the lowest resistance on your ship. Rat with an omni-tank, warp disruptor/scrambler, and webifier fitted. 6) Fit a neutralizer to drain capacitor of the tackling ship.
7) Rat with friends. If several members of corporation are present in system you can always call them for help if you get attacked and cannot kill the attacker or break free.
8) Watch out for warp scrambling rats. If you want to be extra cautious do not engage spawns that might warp scramble you. Leave them be until they despawn.