Any combination of time of exposure and concentration that is less than the recommended level of 22,500 ppm x min is acceptable. Table 2 illustrates acceptable exposure times for varying concentrations of NF3 in air at the EEL of 22,500 ppm x min.

• 任何小于22,500 ppm x min的推荐水平的暴露时间和浓度的组合都是可以接受的。表2说明了在22,500 ppm x min的EEL下，对于空气中不同的NF3浓度可以接受的暴露时间。