ator ▁fully ▁justify ▁inter vent ive ▁actions ▁and ▁carry ▁out ▁documentation ▁before , ▁during , ▁and ▁after ▁the ▁treatment . ▁ ▁One ▁of ▁the ▁gu iding ▁principles ▁of ▁conservation ▁of ▁cultural ▁her itage ▁has ▁tradition ally ▁been ▁the ▁idea ▁of ▁revers ibility , ▁that ▁all ▁inter vent ions ▁with ▁the ▁object ▁should ▁be ▁fully ▁revers ible ▁and ▁that ▁the ▁object ▁should ▁be ▁able ▁to ▁be ▁returned ▁to ▁the ▁state ▁in ▁which ▁it ▁was ▁prior ▁to ▁the ▁conserv ator ' s ▁inter vention . ▁Although ▁this ▁concept ▁remains ▁a ▁gu iding ▁principle ▁of ▁the ▁profession , ▁it ▁has ▁been ▁widely ▁crit iqu ed ▁within ▁the ▁conservation ▁profession ▁and ▁is ▁now ▁considered ▁by ▁many ▁to ▁be ▁" a ▁f uz zy ▁concept ." ▁Another ▁important ▁principle ▁of ▁conservation ▁is ▁that ▁all ▁alter ations ▁should ▁be ▁well ▁documented ▁and ▁should ▁be ▁clearly ▁distinguish able ▁from ▁the ▁original ▁object . ▁ ▁An ▁example ▁of ▁a ▁highly ▁public ized ▁inter vent ive ▁conservation ▁effort ▁would ▁be ▁the ▁conservation ▁work ▁conducted ▁on ▁the ▁S ist ine ▁Chap el . ▁ ▁Conserv ation ▁labor ator ies ▁ ▁Conserv ators ▁rout in ely ▁use ▁chemical ▁and ▁scientific ▁analysis ▁for ▁the ▁exam ination ▁and ▁treatment ▁of ▁cultural ▁works . ▁The ▁modern ▁conservation ▁labor atory ▁uses ▁equipment ▁such ▁as ▁micro scop es , ▁spect rom eters , ▁and ▁various ▁x - ray ▁regime ▁instruments ▁to ▁better ▁understand ▁objects ▁and ▁their ▁components . ▁The ▁data ▁thus ▁collected ▁helps ▁in ▁dec iding ▁the ▁conservation ▁treat ments ▁to ▁be ▁provided ▁to ▁the ▁object . ▁ ▁Country