estaban contaminando
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contaminar

Aunque no todas las mangas contienen fibra de vidrio, todas se estaban contaminando porque la misma cortadora que se usaba para cortar las primeras se usaba para cortar las demás mangas y terminales.
Although not all of the harness sleeves contain fiberglass, all of them become contaminated with its dust because the same cutting machine used to cut fiberglass sleeves is also used to cut other sleeves and terminals.
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