Should a manual high-pressure gate valve be installed in front of an electric high-pressure gate valve?

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I’m a instrumentation technician and am reaching out for help regarding this issue. The factory has installed a new incinerator that generates steam using high-pressure bubbles; there is a 10MPa high-pressure electric gate valve in place. During testing yesterday, the process engineers said that they were conducting trials, and therefore the high-pressure gate valve couldn’t be tested – if it were opened, steam would flow through. I thought it would be sufficient to close the manual valve upstream, but the engineers said there is no such manual valve; the first valve after the bubbles emerges is this electric gate valve. I asked what would happen if the gate valve failed, and they said it isn’t mentioned in the drawings, as they built everything according to those drawings. I’m not sure whether this is normal or not. I’d appreciate it if experts could advise me and let me know if there are any relevant standards