Just curious about accuracy of airport weigh scales...

[WOODMAN]

This sounds paranoid, but is something I have been wondering about for many years now. I am painfully aware of airline weight restrictions on my checked bags, and so I am fairly anal about checking the weight of my bags before I go. Also, I have two different portable weigh scales that I take with me for use on the run. The first is a spring dial scale, and the second is an electronic digital model. Both are hand held devices. I also have a pretty good personal weigh scale at home. I have tested all of these with commercial bags of water softener salt, which are labeled at 40 or 50 pounds, depending on type. I have tried several different bags to get rid of any variance in the packing weight in them, but I have to assume that the labeled weight is pretty accurate. Now, The spring scale can vary a pound or two, and can be sort of hard to read, as you have to look at it while holding it up loaded. Two people work better for this. The digital scale is easier, as it locks the weight reading for you to examine after putting the bag down. This scale is almost always right on the nuts with what the salt bag says it weighs. The home scale is also within a pound or so of the listed weight. Now, with all this, I am fairly certain what my bags weigh, and I always load them to about 45-46# in order to avoid that cursed 50 pound weight limit. But here is the thing. When I get to the check in counter, and the bags go on the scale, they are almost always about 2-3 pounds heavier than when I left home. Curious, wouldn't you say? This has happened to me so many times that I always allow about a 4 pound cushion per bag to deal with this. Now what do you think is going on here? Do you think the bags are picking up ambient moisture from the air during their ride to the airport? I wonder what is going on... Any ideas? Woody

 

[irishsquid]

Do you have to PAY for excess weight? Maybe the old finger on the produce scale trick being used by the airlines?

 

[boulderjohn]

I have occasionally had readings that I thought were wrong myself. However, the scales are regulated. Inspectors come through the airports with official weights to verify the readings. (I saw this being done on the news a couple of years ago.)

 

[DandyDon]

I know that they are regulated, but I am still cynical. I want to do a test sometime soon at my local airport: weight my roll-on with 49-50# total, then check the various airlines at my local airport to see what each scale says.

For now, I limit myself to 48# on my digital scales and hope...!

 

[dmoore19]

Aren't the scales at a federal airport certified by the USDA? That makes me feel sooooo much better.

 

[DandyDon]

DOT probably. The same department that oversees scuba tanks.

 

[boulderjohn]

The problem is, of course, that although they are regulated, they can go bad between tests and there would be no way of knowing. I once flew to Key Largo and back. My dive bag gained 14 pounds while in Key Largo. I know that the gear was still not perfectly dry, but that seems like a lot of weight gain for a little moisture.

 

[WOODMAN]

. My dive bag gained 14 pounds while in Key Largo.

Darn, I knew it! It's that dratted ambient moisture in the air again. I guess I am going to have to hermetically seal my bags after packing, but I guess that would cause me grief with TSA, I suppose. No easy answers, are there? Woody

 

[boulderjohn]

Darn, I knew it! It's that dratted ambient moisture in the air again.

If anything, it was the moisture in the water, not the air. There is no way your gear will be perfectly dry the day after you were diving. Hermetically sealing wet gear won't help.

Of course, I am still joking about that.

 

[DandyDon]

Gear dries slowly in 100% rh ocean breezes, but 14#? That's almost 2 gallons of water.