If sling are to be used in chemically abnormal atmospheres or in constant high temperatures, then seek confirmation of advice before use.

如果吊带用于非正常的化学环境中或用于持续的高温条件下，使用前应征求确认建议。

youdao

Officials are saying there is some evidence of the use of chemical weapons but the US has talked about the need for further confirmation and a UN investigation before being sure.

BBC: Syria chemical weapons claims: UK and US tread cautiously