Standard Methods 23 says you may use plastic bottles for BODs. The 22 edition says it “prefers” glass bottles for dilution water. Can you use plastic for dilution water; such as plastic carboy with stopcock?
There is an interesting study on the subject on internet.
Do a search: Comparative study disposable plastic vs. traditional glass BOD5/CBOD5 Bottles by Marel harstad. It may help you take your decision.
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