Alternatively gas agitation can be used but it isnot recommended when processing films onspirals. If gas burst agitation is in use thennitrogen must be used to agitate the developerwhereas air can be used for the stop bath, fixerand wash. Do not use air to agitate the developersolution. To set up gas burst agitation follow theequipment manufacturer’s instructions, if none aregiven then as a starting point set the gas pressureto 0.3–0.9 bar (5–14 psi) and the agitation cycleto 2 seconds gas on 8 seconds gas off.Alternatively a lower rate of agitation can be usedof one gas burst every other second for elevenseconds in each minute but development timesmay need to be adjusted.