In the article "Chlorine Gas Toxicity From Mixture of Bleach and Other Cleaning Products—California" (MMWR. 1991; 40:619-629, 646 and JAMA. From the Centers for Disease Control. 1991; 266:2529-2534), the threshold limit value (TLV) for chlorine stated in the first sentence of the second paragraph of the (CDC) Editorial Note was incorrectly given as 1 part per million (ppm).
The correct threshold limit value is 0.5 ppm, but a short-term exposure limit of 1 ppm was established for exposures not exceeding 15 minutes.1
Erratum. JAMA. 1992;267(9):1184. doi:10.1001/jama.1992.03480090032011