According to the Oxford English Dictionary: "In Imperial Russia: a secret police department set up in 1881 (after the assassination of Tsar Alexander II) to maintain state security and suppress revolutionary activities, and abolished after the February Revolution in 1917 (now hist.). Also (in later and extended use): the security services of the Soviet Union or its successors."
Okhrana ended in 1917.
I. E. Kuznetsov has written: 'Okhrana truda v tekstil'noi promyshlennosti'
B. I. Vykhristenko has written: 'Trudovye prava molodezhi i ikh okhrana'
Yurii Aleksandrovich Shtyurmer has written: 'Okhrana prirody i turizm'
A. F. Tret'yakov has written: 'Okhrana narodnogo zdorov'ya v RSFSR'
Vilork L'vovich Sidorov has written: 'Tekhnicheskii progress i okhrana truda'
N. V. Razumikhin has written: 'Prirodnye resursy i ikh okhrana'
Lidiya Vasil'evna Speranskaya has written: 'Mezhdunarodno-pravovaya okhrana morskoi sredy'
Il'ya Mitrofanovich Kutyrin has written: 'Okhrana vodnykh resursov-problema sovremennosti'
N. A. Gladkov has written: 'Okhrana prirody' 'Opredelitel' ptits S.S.S.R. =' -- subject(s): Birds
Sharif Tursunovich Atabaev has written: 'Nauchno-tekhnicheskii progress i okhrana okruzhayushchei sredy'
A. P. Semenov has written: 'Okhrana truda v SSSR' -- subject(s): Industrial hygiene