PENNSYLVANIA ASSOCIATION
Of
WEIGHTS AND MEASURES
PO BOX 2511
LANCASTER, PA 17608-2511
www.pawam.org
Press Release
Tech-Memo for L. P. Gas Sales
Spring has sprung, so let’s get out the “Barbie” and make sure the tank is full! It’s that time of year to enjoy the back yard or patio with one of our favorite products, the gas grille. Unfortunately, most consumers and many L. P. Gas industry folks fail to consider or follow many of the rules and regulations that were promulgated for reasons of safety and equity. Let’s discuss the basic requirements for the retail sale of L. P. Gas in portable containers. We’ll cover areas such as the tank or container, the required scale and the method of fill and sale.
L. P. Gas tanks haven’t changed much in the last thirty years with the exception of one or two safety enhancements. They are a welded steel container that will safely hold 20 pounds of compressed liquid product with about 20% head space left for vapor expansion during use or higher temperatures.
The capacity for portable containers is determined by taking the net weight of a tank filled with water (typically about 48 pounds) and multiplying that number by 42 %. (48lbs x 42 % = 20.16lbs. The tare or empty weight of a tank is typically about 18 lbs. This means a tank with a tare or empty weight of 18 lbs would weigh 38 lbs if properly filled. If you weren’t sure before, it should be perfectly clear now that in order to sell L. P. Gas in portable containers, you are required to have an approved scale in an appropriate division size. Based on all state (PA Title 70, 23.106 (d) and federal regulations (Title 49, 178.50-22), L. P. Gas in portable containers must be sold by weight.
This brings us to the scale and weighing procedures. Of course the scale needs to be NTEP or PA type approved and tested and currently sealed by a state or local weights and measures official. The scale must be placed on a level and stable base and be protected from environmental conditions such as wind, rain or snow.
The operator should place the container on a balanced scale to confirm whether the tank is partially or completely empty. The operator may then hook up the fill mechanism, bring the scale into equilibrium and then add to the beam the amount of weight intended for this fill. As the tank is filled, the operator must stay alert, as the beam will rise quickly to the top of the trig loop when the tank is properly filled. Utilizing the bleed off valve or the laboring sound of the fill pump to determine fill is not only incorrect, but very dangerous. After it has been determined that the tank is properly filled, the operator should remove the fill connector and re-check the weight of filled container. The total weight of tank and product should equal the stamped “tare” weight plus the intended fill weight.
A couple of last observations about selecting an appropriate scale with a reasonable division size and the practice of filling portable containers by the gallon with illegal meters.
The typical scale at an L. P. Gas filling station today has a division size of either 4 or 8 ounces. Think about how little sense this makes. The stamped tare weight on an empty tank is allowed an error or variation of 1 % or 2.88 oz. Additionally, the maximum allowable error on a twenty pound fill is 2 % or 6.4 oz. If you are using a scale with 8 ounce graduations, you have already wiped out most of both tolerances. Over the years we have noted some energy firms who have utilized a 300 pound scale with 1 ounce divisions. This is really the proper and appropriate device to be using if you plan to equitably and safely fill portable containers.
How can a consumer protect themselves from improper or illegal filling procedures?
First of all, you should look for the county or state approval decal on the scale. The date on that decal should be no more than 12 months old. After the fill is completed and the fill connector removed, have the clerk gross weigh your filled container. The weight should equal the filled weight plus the tare weight.
Many sales locations are utilizing uncompensated and untested liquid meters to fill portable tanks at retail. This is clearly an incorrect and illegal use of these liquid meters. Our suggestion is, do not utilize these locations if at all possible. Make sure your portable container is properly weighed and filled only by weight. If you have any questions on these procedures, contact PAWM at www.pawam.org .
Pennsylvania Weights and Measures: Setting the Standard for Equity in the Marketplace
*************************
