Change of red and white markings of Polish chimneys

[Obelixx]

When you browse pictures of large chimneys you can find often pictures of the same chimney with different red and white markings ( the pictures of the chimneys of Belchatow Power Station on http://en.wikipedia.org/wiki/File:Be...lektrownia.jpg and on http://pl.wikipedia.org/wiki/Plik:Be...lektrownia.jpg are therefore a good example, but this change of red and white markings occured also on many other chimneys).

What is the reason of change of design of red and white markings when the chimney was repainted?

[kwachu]

Due to change in law: reporting and marking of aviation obstacles.
Obstacles with height in range 10.5-210 m should have 7 red-white strips

Source (in polish) http://isap.sejm.gov.pl/Download?id=...1301193&type=2