Chemical vapor RP offers opportunity

June 1, 2002
MEMBERS of the cargo tank engineering committee at the Truck Trailer Manufacturers Association (TTMA) deserve a round of thanks from the tank truck industry.

MEMBERS of the cargo tank engineering committee at the Truck Trailer Manufacturers Association (TTMA) deserve a round of thanks from the tank truck industry. They wrapped up three years of hard work with the publication of TTMA's new recommended practice for chemical vapor recovery.

The vapor recovery system being recommended by TTMA was developed with extensive input from cargo tank builders, hardware manufacturers, tank truck carriers, and the chemical industry. It is a very workable solution, and the equipment is already on the market.

Tank truck carriers are pretty clear in their enthusiasm for the TTMA recommended practice, which is entitled “Recommended Practice Number 102-02: Vapor Line Configurations for DOT407 and DOT412 Cargo Tanks.” Bill Mangus, safety director for Usher Transport Inc, comments on the recommended practice in an article on Usher Transport that starts on page 14.

“We welcome the new chemical vapor recovery RP from TTMA,” he says. “I hope that NTTC (National Tank Truck Carriers) and the chemical industry will get behind this RP to promote uniformity at the loading racks. We need a standardized vapor recovery system because it's hard to make our trailers versatile enough to handle the variety of systems now in place at chemical plants.”

The recommended practice is something that has been needed for a long time by chemical transporters and the industry they serve. It provides what should be one of the best opportunities for the chemical industry to move toward the same level of vapor recovery standardization that has been in place in the petroleum industry for decades.

Chemical vapor recovery has gained prominence in recent years as federal and state regulations target emissions of chemical vapors, such as volatile organic compounds. One of the most recent regulatory actions was in April 2002, when the Environmental Protection Agency published a Notice of Proposed Rulemaking on National Emission Standards for Hazardous Air Pollutants: Organic Liquids Distribution (Non-Gasoline).

The regulatory activity has been particularly aggressive along the Gulf Coast and in other areas with high concentrations of chemical production facilities. However, more areas of the United States are almost certain to be targeted in the future.

Environmental rules may be the driving force, but vapor recovery, combined with bottom loading, also provides a safety benefit. It keeps drivers and other workers off the tops of tank trailers, which minimizes the potential for falls.

The importance of the safety factor should not be minimized. Even though we haven't seen much regulatory activity, fall protection is on the radar screen at government agencies, such as the Occupational Safety and Health Administration. Chemical vapor recovery and bottom loading give the tank truck and chemical industries an opportunity to show that they are taking a proactive role in preventing falls during loading and unloading operations.

Unfortunately, the current lack of uniformity in vapor recovery systems and chemical plant loading racks means that drivers are still required to clamber on top of tanks. Even worse, they have to lug along the special hardware needed to match up with each plant's vapor recovery system. This just creates more of a fall potential.

Vapor recovery system chaos means that chemical transports must carry an assortment of fittings, not just for the loading rack but for the delivery location as well. If the right fitting isn't on board, the driver must return to the terminal for the right equipment or jury-rig an alternative. The jury-rigged arrangement may or may not be leak-tight.

The solution to all of these problems is now available through the TTMA recommended practice. It's time to embrace the opportunity to standardize chemical vapor recovery.