Narrative:

The following policy has been implemented in ZZZ. The effects of the policy are unsafe -- it has the potential of hiding bleed air leaks. During days of extreme high temperatures; heat buildup in the aft equipment bay on the CRJ200 has caused cargo fire bottles to partially thermal discharge; thus causing the cargo fire bottle low EICAS message. In order to combat this problem; we have rented portable air conditioning units; along with generators; in ZZZ that have ducts that can be placed in the aft equipment bay. Effective immediately; maintenance control will be tasked with daily monitoring of the fleet on the ground in ZZZ. If the ambient air temperature reaches 95 degrees and an aircraft (CRJ200 only) is sitting on the ground for 1 hour or more (scheduled or unscheduled); maintenance control will contact the ZZZ lead technician and advise him that the aircraft requires cooling of the aft equipment bay. Maintenance control will generate an OTS indication that the aircraft requires cooling of the aft equipment bay. Maintenance in ZZZ will make every effort to ensure that the aircraft receives cooling. Placing a ground air cart on the aircraft for the sole purpose of cooling the aft equipment bay is an unsafe practice. The aircraft are made to operate in the temperatures at ZZZ. The effect of putting a ground air conditioning cart on the aft equipment bay can and will hide bleed air line leaks. I refused to follow the above policy due to unsafe procedures. An inspection of the bleed ducts before installation of the ground air cart is necessary. Callback conversation with reporter revealed the following information: reporter stated he is in maintenance control and believes the maintenance directive does not address the issue of pneumatic bleed leaks. The overheat detection system for hot bleed air leaks may not be triggered by a bleed leak; but the cumulative heat build-up in the aft equipment bay will cause a thermal discharge in the cargo fire bottles. Reporter also feels if his company would at least require that mechanics check for pneumatic leaks before attaching the ground air conditioning cart to the aircraft; this would satisfy the issue of known bleed leaks in that compartment area. The cargo fire bottles have a visual pressure gauge on each bottle; as well as the EICAS system cockpit warning fire bottle low pressure indication. Previous reports have been filed; but his company management has not acted on his suggestions.

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Original NASA ASRS Text

Title: CRJ-200 CARGO FIRE BOTTLES TEND TO PARTIALLY DISCHARGE IN HIGH HEAT CONDITIONS. MECHANIC BELIEVES COMPANY DIRECTIVE TO ADDRESS ISSUE IS UNSAFE.

Narrative: THE FOLLOWING POLICY HAS BEEN IMPLEMENTED IN ZZZ. THE EFFECTS OF THE POLICY ARE UNSAFE -- IT HAS THE POTENTIAL OF HIDING BLEED AIR LEAKS. DURING DAYS OF EXTREME HIGH TEMPS; HEAT BUILDUP IN THE AFT EQUIP BAY ON THE CRJ200 HAS CAUSED CARGO FIRE BOTTLES TO PARTIALLY THERMAL DISCHARGE; THUS CAUSING THE CARGO FIRE BOTTLE LOW EICAS MESSAGE. IN ORDER TO COMBAT THIS PROB; WE HAVE RENTED PORTABLE AIR CONDITIONING UNITS; ALONG WITH GENERATORS; IN ZZZ THAT HAVE DUCTS THAT CAN BE PLACED IN THE AFT EQUIP BAY. EFFECTIVE IMMEDIATELY; MAINT CTL WILL BE TASKED WITH DAILY MONITORING OF THE FLEET ON THE GND IN ZZZ. IF THE AMBIENT AIR TEMP REACHES 95 DEGS AND AN ACFT (CRJ200 ONLY) IS SITTING ON THE GND FOR 1 HR OR MORE (SCHEDULED OR UNSCHEDULED); MAINT CTL WILL CONTACT THE ZZZ LEAD TECHNICIAN AND ADVISE HIM THAT THE ACFT REQUIRES COOLING OF THE AFT EQUIP BAY. MAINT CTL WILL GENERATE AN OTS INDICATION THAT THE ACFT REQUIRES COOLING OF THE AFT EQUIP BAY. MAINT IN ZZZ WILL MAKE EVERY EFFORT TO ENSURE THAT THE ACFT RECEIVES COOLING. PLACING A GND AIR CART ON THE ACFT FOR THE SOLE PURPOSE OF COOLING THE AFT EQUIP BAY IS AN UNSAFE PRACTICE. THE ACFT ARE MADE TO OPERATE IN THE TEMPS AT ZZZ. THE EFFECT OF PUTTING A GND AIR CONDITIONING CART ON THE AFT EQUIP BAY CAN AND WILL HIDE BLEED AIR LINE LEAKS. I REFUSED TO FOLLOW THE ABOVE POLICY DUE TO UNSAFE PROCS. AN INSPECTION OF THE BLEED DUCTS BEFORE INSTALLATION OF THE GND AIR CART IS NECESSARY. CALLBACK CONVERSATION WITH RPTR REVEALED THE FOLLOWING INFO: REPORTER STATED HE IS IN MAINT CONTROL AND BELIEVES THE MAINT DIRECTIVE DOES NOT ADDRESS THE ISSUE OF PNEUMATIC BLEED LEAKS. THE OVERHEAT DETECTION SYSTEM FOR HOT BLEED AIR LEAKS MAY NOT BE TRIGGERED BY A BLEED LEAK; BUT THE CUMULATIVE HEAT BUILD-UP IN THE AFT EQUIPMENT BAY WILL CAUSE A THERMAL DISCHARGE IN THE CARGO FIRE BOTTLES. REPORTER ALSO FEELS IF HIS COMPANY WOULD AT LEAST REQUIRE THAT MECHANICS CHECK FOR PNEUMATIC LEAKS BEFORE ATTACHING THE GROUND AIR CONDITIONING CART TO THE ACFT; THIS WOULD SATISFY THE ISSUE OF KNOWN BLEED LEAKS IN THAT COMPARTMENT AREA. THE CARGO FIRE BOTTLES HAVE A VISUAL PRESSURE GAUGE ON EACH BOTTLE; AS WELL AS THE EICAS SYSTEM COCKPIT WARNING FIRE BOTTLE LOW PRESSURE INDICATION. PREVIOUS REPORTS HAVE BEEN FILED; BUT HIS COMPANY MANAGEMENT HAS NOT ACTED ON HIS SUGGESTIONS.

Data retrieved from NASA's ASRS site as of January 2009 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.