UMichel Hart, umhlali waseSan Diego, utyholwa ngokwaphula imithetho karhulumente wase-US ejolise ekuthinteleni ukusetyenziswa kweegesi ezibangela ubushushu. Akukho semthethweni ukungenisa i-hydrofluorocarbons (HFCs) ngaphandle kwee-allowances ezikhethekileyo ezikhutshwe yi-Arhente yoKhuselo lweNdalo (i-EPA) uHart utyholwa ngokuthenga izinto ezipholisa eMexico kwaye azithengise ngokungekho mthethweni e-US ngokuzifihla phantsi kwe-tarpaulin kunye nezixhobo.