5 , ▁ 2 0 2 0 , ▁the ▁standard ▁for ▁smoke ▁will ▁be ▁lower ed ▁to ▁ 2 . 0 ▁g / h .   He aters ▁using ▁the ▁optional ▁cord ▁wood ▁test ▁method ▁must ▁meet ▁a ▁standard ▁of ▁ 2 . 5 ▁g / h . ▁ ▁Just a ▁st ov es , ▁ro cket ▁st ov es ▁and ▁hay box ▁st ov es ▁ ▁In ▁some ▁places , ▁such ▁as ▁the ▁Car ib bean , ▁Central ▁America ▁and ▁South ▁America , ▁many ▁houses ▁have ▁wood - burn ing ▁st ov es ▁that ▁are ▁used ▁ind o ors ▁without ▁any ▁means ▁of ▁proper ▁vent ilation . ▁Sm oke ▁stays ▁in ▁the ▁house , ▁where ▁it ▁is ▁bre athed ▁in ▁by ▁the ▁residents , ▁harm ing ▁their ▁health . ▁Near ly ▁ 2 ▁million ▁people ▁are ▁killed ▁each ▁year ▁by ▁ind oor ▁air ▁poll ution ▁caused ▁by ▁open - fire ▁cook ing , ▁mostly ▁women ▁and ▁children , ▁according ▁to ▁the ▁World ▁Health ▁Organ ization ▁( W HO ). ▁The ▁cutting ▁of ▁large ▁amounts ▁of ▁fire wood ▁also ▁end angers ▁local ▁for ests ▁and ▁e cos ystem s . ▁ ▁Non - g overn ment al ▁organizations ▁( NG Os ) ▁such ▁as ▁Rot ary ▁International ▁are ▁act ively ▁assist ing ▁home own ers ▁in ▁construct ing ▁more ▁fuel - efficient ▁and ▁safe ▁wood - burn ing ▁st ov es . ▁One ▁design ▁is ▁called ▁the ▁Just a ▁st ove , ▁Just ▁st ove , ▁E cost ove , ▁or ▁La ▁Est