13: Summary of assigned local particle reference values and calculation of excursions above such at the point of particle emission and within breathing zones Tier Two assessment Tier assessment Local particle Application of excursion criteria using measured particle Actual Tier Other options for Tier concentrations relative to local particle reference values assessment Three Assessment P reference conducted for the using Workplace Is source Is any single Is breathing Is any R values nanomaterial Exposure Standards emission > 3 source zone value > 3 breathing O a) (WES), Recommended the local emission times the local zone peak C Exposure Standards particle peak value > particle > 5 times E [p cm-3] (REL), proposed reference 5 times the reference value the local S b) exposure standards, or value for local particle for more than particle Benchmark Exposure S more than 30 reference 30 minutes in 8 reference Limits (BEL) [p cm-3] minutes in 8 value? hour day? value? c) PM2.5 hour day? [μg m-3] 1A a) 5.2 x 103 no No no no SMPS data no REL – significant difference in Ultrafine TiO2 b) # n/a n/a n/a n/a count media diameter 300 m-3 μg c) 6.5 no yes = 50 no no μg during or between m-3 process operation at emission point 1B a) 1.2 x 104 no yes = 1.6 x no no Electron microscopy and REL EDX of emission Ultrafine TiO2 105 p cm-3 particles indicated 300 m-3 μg b) # n/a n/a n/a n/a morphology and c) 7.4 no No no no chemical composition similar to raw nanomaterial. 2* a) 6.6 x 103 no yes = 6.0 x # # Electron microscopy and BEL EDX of emission Default insoluble: 104 p cm-3 particles indicated 300 m-3 μg b) # n/a n/a n/a n/a morphology and c) 4.6 no yes = 400 no no μg chemical composition similar to raw m-3 nanomaterial 3^ a) 2.7 x 103 no yes = 1.1 x no no 104 p cm-3 b) # n/a n/a n/a n/a
13: Summary of assigned local particle reference values and calculation of excursions above such at the point of particle emission and within breathing zones Tier Two assessment Tier assessment P R O C E S S Local particle reference values a) [p cm-3] b) [p cm-3] c) PM2.5 [μg m-3] Application of excursion criteria using measured particle concentrations relative to local particle reference values Actual Tier assessment conducted for the nanomaterial Other options for Tier Three Assessment using Workplace Exposure Standards (WES), Recommended Exposure Standards (REL), proposed exposure standards, or Benchmark Exposure Limits (BEL) Is source emission > 3 the local particle reference value for more than 30 minutes in 8 hour day? Is any single source emission peak value > 5 times the local particle reference value? Is breathing zone value > 3 times the local particle reference value for more than 30 minutes in 8 hour day? Is any breathing zone peak > 5 times the local particle reference value? 1A a) 5.2 x 103 no No no no SMPS data – no significant difference in count media diameter during or between process operation at emission point REL Ultrafine TiO2 300 μg m-3 b) # n/a n/a n/a n/a c) 6.5 no yes = 50 μg m-3 no no 1B a) 1.2 x 104 no yes = 1.6 x 105 p cm-3 no no Electron microscopy and EDX of emission particles indicated morphology and chemical composition similar to raw nanomaterial. REL Ultrafine TiO2 300 μg m-3 b) # n/a n/a n/a n/a c) 7.4 no No no no 2* a) 6.6 x 103 no yes = 6.0 x 104 p cm-3 # # Electron microscopy and EDX of emission particles indicated morphology and chemical composition similar to raw nanomaterial BEL Default insoluble: 300 μg m-3 b) # n/a n/a n/a n/a c) 4.6 no yes = 400 μg m-3 no no 3^ a) 2.7 x 103 no yes = 1.1 x 104 p cm-3 no no b) # n/a n/a n/a n/a