| Description: | On 11/29/2012 when the ship was in port, it was noticed that the dry air flow into the
humidigraph was low, about 5 l/min rather than 20 l/min as required. The operators were
directed to check the valve and the HEPA filter.
On 12/5/2012, the operators reported that the Petras air drier had failed totally and it
was later determined that the air pump in the Petras air drier had failed. The humidograph
was repaired 12/13.
Since dry air from the humidograph is used to prepare air flowing into the dry
nephelometer, the data for this instrument is questionable or invalid during the time the
humidograph was out of service and during the time leading up to the failure of the air drier.
Data for this period should be used with caution, if at all. |