H3.1 —— Exposure to Weather, Above Ground Only (室外,地面以上)
H3.2 —— Exposure to weather, above ground; or protection from weather and risk of moisture entrapment (室外,地面以上或者是室内但是有浸淡水风险)
H4 —— Exposure to weather in ground(室外,地面以下)
H5 —— Exposure to weather in ground or freshwater; permanently wet (室外,地面以下或者是永久浸淡水),
H6 —— In ground or seawater; permanently wet (室外,地面以下或者是永久浸海水)