Table 2 Location-level analysis of the change in concentrations of respirable suspended particles after implementation of a smoking ban, stratified by smoking status—North Carolina, 2005–6
Prison typeSize (m3)Average number of burning cigarettes per 100 m3Average particulate matter (PM2.5) less than 2.5 μg/m3% Reduction in PM2.5
Before tobacco banAfter tobacco banBefore tobacco banAfter tobacco ban
Prison areas where smoking was directly observed in 2005 (n = 14)
P1-Dorm area 117120.060.00NANANA
P1-Dorm area 210190.150.00110.5010.770.90
P2-Dorm area 315570.080.0083.25153.450.46*
P2-Dorm area 415570.140.02†NANANA
P4-Dorm area 56790.070.0024.8926.150.05*
P4-Dorm area 66790.240.0073.137.780.89
P4-Dorm area 76790.120.0045.896.280.86
P6-Dorm area 82380.760.00117.518.000.93
P6-Dorm area 9931.510.00304.936.500.98
P1-Lobby/office 10881.890.00193.857.650.96
P6-Lobby/office 11310.000.0030.083.640.88
P3-Dorm area 122192.010.0034.6511.780.66
P5-Dorm area 13‡3400.060.0031.0810.220.67
P3-Dorm area 14¶646.280.0067.599.570.86
Prison areas where smoking was not directly observed and had a locally imposed rule banning tobacco indoors (n = 8)
P3-Dorm area 152190.000.0015.5810.240.34
P6-Dorm area 162380.000.0012.045.630.53
P5-Dorm area 173400.000.0011.565.930.49
P5-Dorm area 183400.000.0016.216.840.58
P2-Lobby/office 19280.000.0012.197.790.36
P3-Lobby/office 20820.000.0010.998.570.22
P4-Lobby/office 211700.000.003.709.791.65*
P5-Lobby/office 22410.000.006.835.320.22
  • NA, technical difficulties. Air monitoring not completed at these sites at baseline.

  • *Percentage increase in PM2.5 rather than a percentage reduction.

  • †Non-compliant prison at follow-up. Directly observed smoking by study team.

  • ‡Dorm area 13 had a non-smoking policy but directly observed smoking occurred during monitoring at baseline.

  • ¶Dorm area 14 was an outside shelter area directly adjacent to a common dorm area door designated for smokers.

  • §Results represent the average of the values for the venues listed in each category.