Document 2J72awY06O5LwE7JOxy6m7bj7

TABLE II COMPARISON OF ASBESTOS SAMPLING METHODS (OPEN-FACE VERSUS CLOSED-FACE WITH PROBEI Mean Parameter Standard Deviation T Statistic* Variance Ratio** Data Open-face cassette: Closed-face cassette: Value 2.2 fibers/mL - open face filter cassette 2.3 fibers/mL - closed face cassette with probe 0.264 fibers/mL - open face cassette 0.286 fibers/mL - closed face cassette with probe 1.28 1.17 1.9. 1.9, 2.0, 2.1, 2.1, 2.1, 2.2, 2.2, 2.2. 2.2, 2.3, 2.9 2.0. 2.0, 2.0. 2.2. 2.3. 2.3, 2.3, 2.4, 2.4. 2.4. 2.5. 3.0 / * 1.28 is less than a comparison t statistic of 1.78 (p0.05). Therefore, the means do not differ significantly. ** 1.17 is less than a comparison'F statistic of 2.69 (p0.05). Therefore, the variances (precision) of the methods do not differ significantly. DUP 0907367