▁The ▁Samuel ▁Ris ley - class ▁ice break ers ▁are ▁a ▁class ▁of ▁two ▁ice break ers ▁and ▁bu oy ▁tend ers ▁constructed ▁for ▁and ▁operated ▁by ▁the ▁Canadian ▁Coast ▁Guard . ▁The ▁two ▁ships ▁are ▁based ▁on ▁off sh ore ▁supply ▁t ug bo at ▁design ▁and ▁entered ▁service ▁in ▁the ▁ 1 9 8 0 s . ▁Samuel ▁Ris ley ▁is ▁deployed ▁to ▁the ▁Central ▁Region , ▁operating ▁mainly ▁on ▁the ▁Great ▁L akes ▁of ▁North ▁America ▁while ▁Earl ▁Grey ▁is ▁posted ▁to ▁Atlantic ▁Canada , ▁working ▁off ▁the ▁east ▁coast ▁of ▁Canada . ▁ ▁Design ▁and ▁description ▁In ▁the ▁late ▁ 1 9 7 0 s , ▁off sh ore ▁supply ▁t ug bo ats ▁were ▁in ▁high ▁demand ▁and ▁their ▁success ▁led ▁to ▁experiment ation ▁by ▁the ▁Canadian ▁Coast ▁Guard . ▁In ▁ 1 9 8 0 , ▁a ▁c rane ▁was ▁tempor arily ▁installed ▁ab o ard ▁the ▁former ▁off sh ore ▁supply ▁vessel ▁, ▁situated ▁on ▁the ▁after deck . ▁This ▁was ▁done ▁to ▁see ▁if ▁this ▁would ▁be ▁a ▁successful ▁model ▁for ▁bu o yt ending . ▁Jack man ▁visited ▁all ▁the ▁principal ▁coast ▁guard ▁stations ▁in ▁the ▁eastern ▁half ▁of ▁the ▁country ▁to ▁test ▁the ▁setup ▁in ▁different ▁conditions ▁in ▁ 1 9 8 0 – 8 1 . ▁The ▁results ▁of ▁the ▁test ▁proved ▁positive ▁and ▁in ▁ 1 9 8 3 , ▁the ▁Canadian ▁Coast ▁Guard ▁contract ed ▁Robert ▁Allen ▁Ltd ▁of ▁V ancouver ▁to ▁create ▁a ▁design ▁based ▁on ▁this ▁setup .