Working level month (WLM) means an exposure to 1 working level for 170 hours (2,000 working hours per year divided by 12 months per year is approximately equal to 170 hours per month).
Working level (WL) means any combination of short-lived radon daughters in 1 liter of air that will result in the ultimate emission of 1.3E+5 MeV of potential alpha particle energy. The short-lived radon daughters are—for radon-222: polonium-218, lead-214, bismuth-214, and polonium-214; and for radon-220: polonium-216, lead-212, bismuth-212, and polonium-212.
Barrier Level means the Barrier Level as specified in § 1 of the Product and Underlying Data.
Digital Signal Level 0 (DS-0 means the lowest-level signal in the time division multiplex digital hierarchy, and represents a voice-grade channel operating at either the 56 Kbps or 64 Kbps transmission bit rates. There are twenty-four (24) DS-0 channels in a DS-1.
Index Level means, in respect of any day and subject to Adjustment Provisions: (a) in respect of an Index (other than a Multiple Exchange Index), the closing level of such Index at the Valuation Time on such day; and (b) in respect of an Index that is a Multiple Exchange Index, the official closing level of the Index on such day at the Valuation Time as calculated and published by the Index Sponsor each as rounded up to four decimal places (with 0.00005 being rounded up), all as determined by the Calculation Agent.