Narrative:

During the climb at 250 KTS; we received a hydraulic 1 lo pres caution message. We ran the QRH which specified turning on the hydraulic 1(b) pump and to monitor the system. The psi was down at 500 psi and climbed slowly up to 2;800 psi and held there. The temperature was at 40; climbed to 45; then cooled to 27 degrees C enroute. By landing; the temperature was up to 33 or so and we figured this was due to warmer air near the surface as system 2 was indicating roughly the same upon landing. The tank quantity indication indicated dashes (--) and thus; we had no clue how much fluid was in the tank. Being that the electric pump was maintaining pressure; we figured there had to be enough for the pressure to return and remain constant. Once this pressure was restored; we got another message; hydraulic edp 1A. We ran the QRH which basically said to monitor the system and note how long the engine driven pump was running without fluid. We took another look at the low pressure QRH and looked again at the decision tree. We had pressure but we had no clue how much was in the tank. We then got on arinc to call maintenance control to discuss our findings and they agreed with us that since we had pressure; there had to be enough fluid in the tank to keep pressing on to [destination] and not divert to the nearest suitable airport. We all agreed that if the pressure would subsequently drop; a landing at the nearest suitable airport would be required and I ascertained a few airports along the way that would be suitable. We continued to [destination] without incident and upon post flight walk around; hydraulic fluid was dripping from the aft equipment bay; a quick look inside revealed nothing other than a wet aft bay. Contract maintenance eventually showed up and we were rescheduled to deadhead back to base. I didn't like the way the decision tree was presented: 'system 1 quantity readout is less than 5% or pressure is less than 1;800 psi; or pressure is rapidly decreasing' being that there is no comma (;) between 'less than 5% or pressure is less than 1;800...'; are those two items grouped together and separate from 'or pressure is rapidly decreasing'; or are there three conditions in which you would have to divert to the nearest suitable. A better way to word the QRH decision tree could be: system 1 quantity readout is less than 5%; or pressure is less than 1;800 psi; or; pressure is rapidly decreasing. Then it would be perfectly clear that if you had one of three conditions; you must follow that route and land at the nearest suitable. In our case; we had pressure; but had no clue how much quantity was in the tank. Had we known the quantity was less than 5%; we would have landed at the nearest suitable. [Someone] could ask maintenance how much fluid is required to keep the electric pump running.

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Original NASA ASRS Text

Title: A CRJ-200 Captain reported loss of pressure in #1 hydraulic system and encountering some confusion with the QRH. After consulting with Maintenance they decided to continue to destination.

Narrative: During the climb at 250 KTS; we received a HYD 1 LO PRES caution message. We ran the QRH which specified turning on the Hydraulic 1(b) pump and to monitor the system. The PSI was down at 500 PSI and climbed slowly up to 2;800 PSI and held there. The temperature was at 40; climbed to 45; then cooled to 27 degrees C enroute. By landing; the temperature was up to 33 or so and we figured this was due to warmer air near the surface as System 2 was indicating roughly the same upon landing. The tank quantity indication indicated dashes (--) and thus; we had no clue how much fluid was in the tank. Being that the electric pump was maintaining pressure; we figured there had to be enough for the pressure to return and remain constant. Once this pressure was restored; we got another message; HYD EDP 1A. We ran the QRH which basically said to monitor the system and note how long the engine driven pump was running without fluid. We took another look at the low pressure QRH and looked again at the decision tree. We had pressure but we had no clue how much was in the tank. We then got on ARINC to call Maintenance Control to discuss our findings and they agreed with us that since we had pressure; there had to be enough fluid in the tank to keep pressing on to [destination] and not divert to the nearest suitable airport. We all agreed that if the pressure would subsequently drop; a landing at the nearest suitable airport would be required and I ascertained a few airports along the way that would be suitable. We continued to [destination] without incident and upon post flight walk around; hydraulic fluid was dripping from the aft equipment bay; a quick look inside revealed nothing other than a wet aft bay. Contract Maintenance eventually showed up and we were rescheduled to deadhead back to base. I didn't like the way the decision tree was presented: 'System 1 quantity readout is less than 5% or pressure is less than 1;800 PSI; or pressure is rapidly decreasing' being that there is no comma (;) between 'less than 5% or pressure is less than 1;800...'; are those two items grouped together and separate from 'or pressure is rapidly decreasing'; or are there three conditions in which you would have to divert to the nearest suitable. A better way to word the QRH decision tree could be: System 1 quantity readout is less than 5%; or pressure is less than 1;800 PSI; or; pressure is rapidly decreasing. Then it would be perfectly clear that if you had one of three conditions; you must follow that route and land at the nearest suitable. In our case; we had pressure; but had no clue how much quantity was in the tank. Had we known the quantity was less than 5%; we would have landed at the nearest suitable. [Someone] could ask maintenance how much fluid is required to keep the electric pump running.

Data retrieved from NASA's ASRS site as of April 2012 and automatically converted to unabbreviated mixed upper/lowercase text. This report is for informational purposes with no guarantee of accuracy. See NASA's ASRS site for official report.