If the oxygen requirement reaches 700 metric tons, lockdown will be imposed again, he said in a statement. The daily oxygen production capacity in the state is 1,300 metric tons, he said. ''During the second wave, when the number of COVID-19 cases showed a steep spike, the demand for oxygen was also very high. Some 500 metric tons of oxygen had to be procured from other states. If the demand goes up to 700 metric tons daily, which is the quantity needed for nearly 30,000 patients, the state will be once again brought under lockdown,'' Thackeray said.