Conventional tear gas is CS, which replaced CN. DM was the nausea agent. CS is more potent than CN but was found to be less toxic in the long run.
Pepper spray (OC) may actually be even more potent than CS, depending on the concentration.
CS spray is a highly diluted form of CS (dissolved in liquid). In the US, CS spray is typically just 1% CS. UK police uses 5% CS.
Mace, the popular personal protection brand, was originally based on 1% CN. Now it is mostly pepper spray (up to 10% OC), but the company still makes products with CN.