Contributed by Bob Chabot

The Future of Heavy-Duty Cab Environments

Will future environmental cabs be government-regulated or free market-driven?

Cleaning up heavy-duty, off-road operator enclosed cab environments is an ongoing struggle. Medical research shows extended exposure to a wide variety of airborne particulates can be harmful to operators. Industry experience also tells us that extended exposure to a wide variety of airborne particulates is harmful to equipment. Both have consequences that can be measured in dollars and lives.

Without consultation, government regulation can lead to dead ends

The business of removing dirt from the air prior to its entry into an intake on an engine or the HVAC system knows no geographic boundaries. Airborne particulate — whether at a coal mining operation in Alabama, a sandstone quarry in Australia or inside a waste recycling facility in Europe— has a devastating effect on heat exchangers, evaporator cores, electronic equipment and the environment inside an operator cab.

As industrial engineers grapple with finding cost-effective and safe solutions, governments have mandated and are considering more regulations and specifications for cleaning up cab environments. For example, the U.S. Occupational Safety & Health Administration (OSHA), has developed industry-specific, maximum exposure level measures for most airborne toxins, gases and particulates. Regulations typically focus on PELs during a work shift as the primary guideline.

In the past, the health effects of hazardous working environments were considered part of the job. Today, keeping workers healthy has governments, labor unions and insurance companies pushing to reduce workplace exposure to breathable dust and airborne toxins commonly associated with operating heavy duty equipment. These measures include Occupational Exposure Limits (OEL), Permissible Exposure Limits (PEL) and Time Weighted Average Exposure Limits (TWA).

Under the guise of ‘public safety,’ regulators have sometimes moved ahead of, and often independently from, research scientists and cab manufacturers when mandating air quality standards that were not achievable with known technologies. This lack of consultation can lead to misallocated capital, increased machine cost, a frustrated engineering community and consequences worse than the original concern.

Setting the Bar

The Centers for Disease Control published Key Design Factors of Enclosed Cab Dust Filtration Systems in 2008, which has become the seminal work in understanding the fundamental requirements of heavy duty cab and HVAC design. It demonstrated that high-efficiency filtration and zero seal leakage are required to provide high-quality air environment to the HVAC and cab operators. To read the complete study, click here. (Images — Centers for Disease Control)

Measuring ‘In-Use’ Heavy Duty Emissions Data
The Portable Eemissions Measurement (PEM) unit — developed by the EPA, Sensors Inc. and Eastern Research Group — can be temporarily fitted by crane to heavy duty equipment to measure CO2, CO, THC and NOx emissions while the equipment is in use. (Image — Sensors Inc.)

“Sometimes, in trying to solve a relatively harmless problem we create a far more dangerous one,” notes Jeffrey L. Moredock, vice president of sales for Sy-Klone International < Link —http://www.sy-klone.com> . He cites a U.S. regulation that required that diesel engine exhaust be reburned to reduce the black smoke or unburned diesel fuel emissions. Reburning the exhaust caused subsequent emissions to go from relatively large particle to much smaller particles in the 0.3 micron size range. The human respiratory system cannot clear itself of these smaller particles, which remain in the lungs and are more likely to cause illness.

In addition, the accurate and practical measurement of cab air quality with sensitive testing instruments is challenged by real-world humidity, high dust concentrations and intense vibration. In 2009, for example, the European Union approved a regulation that required so high a degree of accuracy in the measurement of the contaminants in agricultural sprayer cabs that even the most sophisticated labs in the world would have a difficulty measuring. Any original equipment manufacturer (OEM) shipping to Europe was faced with an expensive, impractical, unfeasible task.

Recently, the Society of Automotive Engineers <Link to article — http://www.sae.org/mags/SOHE/9258 > reported the EPA and its research partners have developed a portable emissions measurement unit that can be temporarily fitted by crane to heavy duty equipment. The EPA says that in a small field project, it was able to determine, while in-use, time-resolved (1-hz) gaseous pollutant mass emission rates (CO2, CO, THC and NOx) of heavy duty equipment. It remains to be seen if this device can maintain its efficacy amidst humidity, dust and vibrations over time.

Cleaner Air Plus Cost Reduction
T A Hall General Contractors Inc. operates a coal operation in Alabama. Their machines run continuously and experienced regular premature HVAC failure – on average every three months – due to coal dust clogging the evaporator core. The average repair cost per incident exceeded $7,000. After installing Sy-Klone’s International’s RESPA® Cab Air Quality System equipped with Gideon® particle separation technology, the new machine experienced no HVAC failure in the following six months of operation and there was a dramatic reduction in filter replacement. The above images show the evaporator core before (left) and six months after (right) operating with the new technology (right). (Image — Sy-Klone International)

Those closest to the problem are in the best position to solve it

Modern environmental cabs and associated HVAC systems must increase operator productivity, reduce breathable particulate and work maintenance-free for longer periods of time. In the absence of industry-provided solutions, it’s true that regulators will mandate change ‘in the public interest,’ without regard or concern for the impact on cost or productivity. Consequently, industry cannot wait for the government to regulate them before taking action.

In addition, as exposure measures become more stringent, complying becomes difficult. “If industry waits for the regulators to dictate cab design, they will find themselves bound by a spool of red tape that creates huge disincentives to innovation and ultimately creates a dependency that is unsustainable for the heavy equipment industry, its customers and its operators. Recognizing that health and safety also affect the company’s bottom line, OEMs must look for ways to reduce workplace exposure to breathable dust and airborne toxins,” says Moredock.

“Industry is in the best position to make cost -effective, consumer-driven improvements to their operator cabs which enhance the value of the machine and the marketability of their product,” he adds. “When regulators dictate solutions, they are often difficult to implement, costly to administer and ineffective in addressing the problems.”

Moredock shares an example where collaboration worked. “Recently, the Sy-Klone representative in Canada was following up with the Occupational Safety and Health Administration regarding their interest in our environmental cab solution — RESPA® with Gideon® particle separation technology — which we had demonstrated at a local trade show.”

“Curiosity regarding our product resulted in an invitation to demonstrate it to the OSHA staff. They also told us, ‘We are going to let industry figure out the best solution. However, we want to understand your RESPA® system, and we would appreciate your willingness to share it with our staff.’ This was a great response from a governmental agency and will be one reason, I believe, that Canada will be successful in getting real solutions into the market place.”

A fork in the road ahead

“The question is simple,” Moredock asserts. “Will industry act in the consumer’s best interest and provide the most cost-effective solutions, or will government regulation be the driving force for change? The best approach puts industry in the driver’s seat, as it results in lower costs, higher performance environmental cabs and ongoing technological advancement.”

Beyond operator safety, there are other compelling economic reasons for improving the air quality in an enclosed cab environment. The challenge of employing high-efficiency filtration to keep dirt off the evaporator core and out of the operator environment over extended periods of time allows the rethinking of HVAC and environmental cab design.

Conventional engineering effort has been focused on how to keep the HVAC system working properly while pressurizing the cab. The most common approach to cleaning air before it goes into the fresh air plenum is with a fresh air filter. But with very little loading, these filters become too restrictive for the fan to effectively pull air through it without stalling. To prevent this, a blower motor was then employed to draw more fresh air through the fresh air filter. Yet this also pulls 100 percent of the dirt in the air stream onto the filter, causing it to clog quickly and lose the ability to pressurize the cab. The addition of a nonpowered precleaner decreases blower motor efficiency, as it cannot overcome the restriction added by the precleaner.

A Global Industry-Led Solution
Sy-Klone International’s patented RESPA® Cab Air Quality System, equipped with powered Gideon® particle separation technology, allows mobile enclosed cab HVAC systems to perform at cleanliness levels previously impossible to attain required levels in many industries and jurisdictions around the world. (Image — Sy-Klone)

This typical industry approach has been a series of compounded band-aid attempts to improve filtration that resulted in low filtration efficiency, more frequent filter changes, filter seal leakage and machine downtime. Moredock says that adequate technology to bring environmental cabs into compliance exists and that the industry has the technology and know-how to resolve issues before they become objects of the regulators’ attention, anywhere in the world.

“The technology that allows for major advancements in cab air performance is relatively new and unknown to many cab manufacturers,” adds Moredock. “Nor is it is understood by many in the engineering community. In part, this is because the engineering issues associated with developing a functional environmental cab in a heavy debris concentration, high-vibration work environment are complex.”

Monitoring Protects Value
A pressure monitor and in-cab telemetry system proactively monitor critical, real-time data within a HVAC system. This enables cost-effective cab air filter changes and the identification of potential failures before they result in costly machine downtime. (Image — Sy-Klone)

An industry-led solution for a multi-industry, multijurisdiction problem
OEMs sell their products to more than one country, each with its own regulations that drive up costs further and decrease manufacturing efficiencies. On one hand, the operator cab is one of the least expensive environments in which to control air quality, making it a major factor in reducing the average daily exposure rate to harmful substances. On the other, the inability to provide high-efficiency fresh and recirculated filtered air had been the greatest roadblock to the development of sustainable, low-cost maintenance environmental cabs.

“But that has recently changed,” says Moredock. “The future of environmental cabs will include sustainable, low-cost, powerful engineering controls that will empower the operator and owner to maximize the productivity of the machine by minimizing operator and machine downtime. Sy-Klone International’s technology — the patented RESPA® Cab Air Quality System with a powered Gideon® precleaner — is one example of an industry-driven solution for clean, safe enclosed cab HVAC systems.”

“RESPA® is the bridge to the future of environmental cabs,” Moredock explains. “It is able to cost-effectively provide high-efficiency fresh and recirculation air filtration, long filter service life, cab pressurization and extended service intervals on HVAC components. In addition it provides high-quality air to the operator allowing for compliance to the myriad of air quality regulations within various industries and countries around the world.”

Moredock insists that by taking a proactive approach, environmental cab technologies will continue to advance. “Industry can grow with less regulatory burden, while also providing the customer with what they want — low cost, low maintenance, environmental cabs that protect the operator and increase productivity.”

Would you agree?