Hazardous Area Classification and Ventilation of Golf Cart StorageArea

[joerob]

I am currently reviewing a new golf clubhouse which includes a golf cart storage area in the basement. These golf carts are battery powered, and thus undergo re-charging. I know that during the re-charging process, hydrogen gas if given off. The storage area is equipped with a hydrogen gas monitoring system which turns on and exhaust system when the hydrogen level is detected as 20% of the lower explosion limit (lel), and shuts off power to all of the battery chargers and alarms if 40% lel is reached.

In addition to the above, I am considering incorporating the following measures. I feel that the cart storage area should be electrically classified as a Class I, Zone II hazardous location, since failure of the ventilation system could lead to the presence of dangerous level of hydrogen in the area. Additionally, I am considering de-energing all devices in the area if 40% lel is reached, not just the chargers. And finally, all equipment that is to remain operational in the event that 40% lel is reached should be installed in accordance with Class I Zone II requirements, such as the hydrogen detection system, emergency lighting, fire alarm, etc. The remainder of the equipment does not need to be classified for non hazardous areas as it would be de-energized.

Does anyone have any experience with golf cart storage area ventialation and classifications? Do the above measures of using Class I Zone II components seem like overkill since by shutting the battery chargers off, the release of additional hydrogen should be limited, or should all equipment in the area be of Class I Zone II type?

Comments are appreciated.

 

Dear Joerob:

I don't have experience in this king of areas, but I believe you're approaching the issue the right way. Although I would also consider evaluating the ventilation system. This system must be designed and installed according to the proper electrical classification due to the use or application of the equipment. One more thing to consider is the natural ventilation. How does the outside air or wind affect the room ventilation? Does the natural ventilation influences over the mechanical ventilation performance?

If you still consider at the end to classify the area as Class 1, Zone II, then the ventilation system must by in accordance with it.

 

[Slowzuki]

I have a follow up question to this, what hazard grouping are common electrical outlets?

I can't seem to find an answer other than my intuition says they spark.

We are trying to find out if normal outlets can be used in a Class 1 Division 2 area if gas detection, shut down and ventiulation requirments are met.

Ken