Table 2.
Data Recovery Rates and Frequency Distribution of PM2.5 Measurements by Three Different Threshold Categories by PA Time Periods in the MA3 Pilot Study.
| Country * | Town & City | Number of Records Logged (n) | PA° Time Periods (N) | Data Recovery Rates (%) | >10 μg/m3 n > 10 (%) |
>25 μg/m3 n > 25 (%) |
>250 μg/m3 n > 250 (%) |
|---|---|---|---|---|---|---|---|
| The Gambia | Fajara, Kombo | 20,636 | 22,320 | 94.7% | 11,455 (55.5%) | 1644 (8.0%) | 78 (0.4%) |
| Burkina Faso | Balkuy, Ouagadougou | 21,142 | 22,320 | 94.7% | 16,026 (75.8%) | 4647 (21.9%) | <0.1 (0%) |
| Benin Republic | Akpakpa, Cotonou | 30,799 | 33,480 | 92.0% | 29,262 (95.0%) | 9178 (29.8%) | 3 (0.01%) |
| Nigeria | Abakaliki Rd, Enugu | 32,999 | 33,480 | 98.6% | 30,437 (92.2%) | 15,972 (48.4%) | 13 (0.04%) |
| Nigeria | Trans-Ekulu, Enugu | 31,139 | 33,480 | 93.0% | 28,428 (91.3%) | 15,178 (48.7%) | 28 (0.09%) |
| Nigeria | Goshen, Enugu | 35,322 | 33,480 | 105.5% | 32,512 (92.0%) | 18,084 (51.2%) | 4 (0.01%) |
| Nigeria | New Haven, Enugu | 31,241 | 33,480 | 93.3% | 29,569 (94.6%) | 18,811 (60.2%) | 4 (0.01%) |
| Nigeria | Awka, Anambra | 31,500 | 33,480 | 94.1% | 29,343 (93.2%) | 20,003 (63.5%) | 18 (0.06%) |
| Kenya | Ngong Rd., Nairobi | 22,320 | 22,320 | 100.0% | 21,322(95.5%) | 16,944 (76.0%) | 11 (0.05%) |
| Nigeria | Nnewi, Anambra | 21,078 | 22,320 | 94.4% | 20,500 (92.3%) | 16,944 (80.4%) | 173 (0.82%) |
| Uganda | Ntinda, Kampala | 21,312 | 22,320 | 95.5% | 21,293 (99.9%) | 19,605 (92.0%) | 276 (1.3%) |
| Nigeria | Bariga, Lagos | 24,148 | 33,480 | 72.1% | 24,062 (99.6%) | 23,113 (95.7%) | 22 (0.09%) |
°PA stands for PurpleAir time periods. This represents the ideal number of logs each device is meant to have over the 31 days, assuming it logs every 80 s (33,480) or 120 s (22,320). * Cameroun was excluded from the analysis since the devices did not log any data.