Table 1

Study prison characteristics and data collection dates

PrisonHMP 1HMP 2HMP 3HMP 4
Category and function*Male
Category B
Local		Male
Category C
Training		Male
Category C
Training		Male
Category C
Training
Structural designBuilt 1850s
Victorian radial design		Built early 1800s
Singular wings		Built 1974
Five two story living blocks and quick build wings		Built 1960s
Mix of triangular, T-shaped and quick build wings
No of wings7799†
Smoke-free implementation date11/04/1625/04/169/05/1623/05/16
Prisoner roll count pre-policy505634706518
Prisoner roll count post-policy477628691378†
Sampling dates pre-policy19/01/16 – 23/01/1608/02/16 – 11/02/1615/02/16 – 18/02/1629/02/16 – 02/03/16
Sampling dates post-policy05/07/16 – 08/07/1618/07/16 – 21/07/1622/08/16 – 25/08/1615/08/16 – 17/08/16

  • *Category B prisons hold prisoners for whom the very highest conditions of security are not necessary but for whom escape must be made very difficult. Category C prisons hold prisoners who cannot be trusted in open conditions but who do not have the resources and will to make a determined escape attempt. Local prisons serve the courts and receive remand and post-conviction prisoners prior to their allocation to other establishments. Training prisons hold sentenced prisoners who tend to be employed in a variety of activities such as prison workshops, gardens and education and in offending behaviour programmes.

  • †HMP 4 closed two wings (and transferred all prisoners located on these wings) between pre- and post-smoke-free data sampling dates.

  • HMP, Her Majesty’s Prison.