After plenty of controversy, the city's new sugary drink regulations finally take effect on Tuesday.
City Department of Health officials say their inspectors will use specially ordered cups that can hold 17 ounces.
They will issue a violation only when a cup clearly exceeds the 16-ounce limit.
Officials said the special cup will allow businesses a margin of error.
Speaking on Sunday on CBS' "Face the Nation," Mayor Michael Bloomberg once again defended the ban, saying the city is not interested in telling people what to do, but about showing them how controlling portions can improve their health.
"If you want to have 32 ounces, just buy two 16-ounce cups, take them back to your seat. If you want 64 ounces, take four cups back. But what's likely to happen here is you'll take one and probably not come back for the second. But it's totally your choice. We're not banning anything," said Bloomberg. "It's called portion control. It's a typical way that companies use and governments use to explain to people what's in their interest and what isn't."
Businesses that receive inspection grades from the Department of Health are covered by the rule.
Health officials say the frequency of inspections will depend on the individual businesses' letter grade.