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Teaching forklift maintenance is vital

May 1, 2003 By    

by Bill McGlinchey

Concerns for the environment have moved indoors. The health and safety of employees in the workplace have long been an issue with OSHA, but more recently the Environmental Protection Agency has promulgated large spark ignited (LSI) engine emission regulations that are already impacting the forklift market.

Historically, the forklift industry has been plagued by misleading and often conflicting reports of the relative tailpipe emissions from various fuels. This has led many of the estimated 95,000 end-users in this market to switch between those fuels without the benefit of accurate, apples-to-apples information.

The Propane Education & Research Council recently funded a Forklift Technician Maintenance Training Program to focus on the proper adjustment and measurement of forklift fuel systems, particularly those running on propane.

The task of estimating the environmental impact of reduced emissions as a result of a technician-training program has proved to be a difficult one. The question, however, is no less valid as this attempt to answer it.

Previous calculations were based on empirical estimates of the effect of reduced carbon monoxide using percentage volume exhaust gas analyzers. They beg the question: Percentage volume of what? Today’s EPA regulations require mass measurements. However, emission inventory models developed for over-the-road vehicles are not applicable to the indoor market.

This model uses the latest ISO C2 steady state drive cycle as the basis for mass estimates of carbon monoxide at various levels. The data is from a GM 1.6L forklift running on propane.

It should be noted that a complete emission model would consider additional crankcase, diurnal, hot soak, refueling and running losses, as well as the actual drive cycle results. But it was felt that these were beyond the scope of this analysis.

Extrapolations for the mass emission inventory and subsequent reductions for various scenarios can be made from these laboratory measurements.

Ambiguity begins with the estimate of the current propane forklift population. The most recent figures come from the EPA in their latest LSI emission regulation documents. The complete report – Final Regulatory Support Document: Control of Emissions from Unregulated Nonroad Engines – can be found at: www.epa.gov/otaq/largesi.htm.

Current EPA figures based on sales data from the Industrial Truck Association, the growth rate per year, scrap page, etc. set a year 2000 baseline of 499,693 units. Of those, an estimated 95 percent run on propane. This gives us a starting population of 474,708 units with pre-catalyst, open-loop technology, the target population of the Technician Training proposal.

Further, the EPA bases its inventory estimates on an average forklift horsepower rating of 69 hp and an average usage of 1,800 hrs per year. I will use these same estimates.

This suggests a range of four to 57 tons of carbon reduction per unit per year if carbon monoxide were reduced closer to a stoichiometric value of 0.5 percent. The implications of this are significant. The training proposal specifically focuses on the pre-2000 ‘gross polluters’ of the forklift market. Values of 4 to 8 percent CO are not uncommon.

How many forklifts will be affected by the training? The program requires a minimum of 20 classes for the first year and a minimum class size of 15 students. If these included 10-15 different companies, the number of companies impacted would be 200 to 300. The number of forklifts affected, based on the Gas Research Institute study average of four per company, is conservatively 800 to 1,200 units.

In conclusion, one could reasonably estimate that in the first year of the pilot training program the environmental impact in terms of potential carbon monoxide reduction could be between 3,000 and 68,000 tons, based on the severity of the starting fuel mixture and the ability of the technician to properly adjust and maintain a stoichiometric air-fuel ratio.

McGlinchey is president of AFV Consulting LLC, which received the recent PERC grant to study forklift emissions. He served 10 years as facility manager for the National Alternative Fuels Training Consortium at West Virginia University before retiring in June 2002.

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