Prior to removing the access doors to a pressure vessel for internal maintenance it should be ensured that all pressure has been relieved. As well as a zero indication on a pressure gauge which other measure, from the options given should be taken to confirm this prior to commencing the work?
Правильный ответ:
Open the drain valve while pressure still shows on the gauge and to check it is clear. Outflow should cease as the pressure gauge reaches zero.Ваш ответ:
Open the drain valve and when the outflow stops slacken off the drain valve flange bolts and “crack” open the flange in case the drain is blocked.