in the clear

Stephen KingのThe Girl Who Loved Tom Gordonを読み始めました。
家族で山歩きに来ていた９歳の少女Trishaは小用の為に皆から離れ、そのせいで遭難してしまいます。
つい最近、世界的に有名な女性登山家が遭難したとのニュースを思い出しましたが、Trishaは大丈夫でしょうか？
Halfway out, something moved under her. She looked down and saw a fat black snake slithering through the leaves. For a moment every thought in her mind disappeared into a silent white explosion of revulsion horror. Her skin turned to ice and her throat closed. She could not even think the single word snake but only feel it, coldly pulsing under her warm hand Trisha shrieked and tried to bolt to her feet, forgetting that she wasn't yet in the clear. A stump of branch thick as an amputated forearm poked agonizingly into the small of her back.
"in the clear" は慣用句のようなので辞書を見ます。
・Collins Dictionary: free of suspicion, guilt, or blame: You ought to be able to alibi each other, put everyone in the clear.
・The American HeritageR Dictionary of Idioms: Free from danger or suspicion of wrongdoing, as in: The evidence showed that the suspect was actually in the clear.
ここではまだ蛇の危険（？）から逃れてはいないの意味のようです。
上の引用個所の最後に出てきた "small" は 12/31/2011 にカズオ・イシグロのNever Let Me Goで覚えた単語です。