Moisture
While relative humidity measures the percentage of water in the air at a particular temperature , as in grains of moisture per pound of dry air , GPP measures the weight of water in the air . Relative humidity is different because it is a relative measure denoted by the percentage of moisture in the air , which changes with air temperature . Impact In mechanics and physics , shock is a sudden acceleration , positive or negative , caused by impact or some other physical force . Impact is a transient physical excitation measured in g-force , where weightlessness denotes a zero g-force value , while gravity ’ s effect on weight is equal by definition , to 1g .
Results In-Transit Temp The environmentally controlled vehicle can achieve the temperature and humidity parameters within 1 to 2 minutes after vehicle and HVAC is turned on .
Mean-kinetic temperature results show that the tray temperature levels were within designated temperature and humidity parameters while vehicle is out on routes ( engine running , stopped and engine off for pick-up and delivery even for extended periods ) .
EC van could maintain the temperature within the standard range and remained very consistent .
Neither SUV ( tray in the back of the vehicle ) with air conditioning , nor trunk of passenger car could maintain tray temp below 75 degrees F .
Moisture weight stayed within the 50 to 60 gpp range . Tray humidity in all vehicles for dynamic testing stayed below the 60 % maximum per standards .
In-Transit Relative Humidity
Humidity levels during the dynamic testing for inside the environmental controlled vehicle and the tray stayed within the standard range .
Additionally , data showed that Dew point stayed within the comfortable range .
Dew Point
Dew Point values : less than or equal to 55 is dry and comfortable , 55 to 65 becomes sticky to hot , and greater than 65 is oppressive .
Additionally , data showed EC vehicles can maintain dew point for trays while personal vehicles cannot maintain the lower values and can be a significant concern for moisture within the trays .
Dew point stayed within the comfortable range of 54 degrees F for EC vehicle ( 1 hour 15 minutes ).
Dew Point in the back of the SUV started at 54 degrees F but rose to 60 degrees F , a sticky and hot range ( 1 hour 10 minutes ).
Dew point in the trunk of a passenger car started at 54F but quickly rose ( less than 30minutes ).
april 2024 • www . healthcarehygienemagazine . com •
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