Section 24 in Delhi Prisons (Transfer of Prisoner, Labour and Jail Industry, Food, Clothings and Sanitation) Rules, 1988
24. Different kinds of conveyance by rail.
(1)Prisoners may be conveyed by rail in :-(a)ordinary second class carriages ;(b)second class carriages with iron gated windows and iron railings between the compartments, and(c)prison vans:(2)(a)When the prisoners escorted are aged, feeble, sick, crippled, women, children, or are accused of minor offences, or are not desperate characters, or are harmless lunatics, or where the number of persons including the escort does not exceed five, they may be conveyed in ordinary second class carriages. The escort shall sit on each side of the prisoners and guard the doors.(b)Prisoners of exceptionally dangerous character, who require extra vigilance for their safe custody shall be conveyed in custody by jail in prison vans only. If prison van is not available alternative mode of transportation may be sent by the Commissioner of Police
