Staying in compliance with the Permissible Exposure Limit (PEL) is now becoming more of a concern. The National Advisory Committee on Occupational Safety and Health (NACOSH) is calling on the Office of Management and Budget (OMB) to finish its review of OSHA’s proposed silica standard so that the rule (RIN 1218-AB70) can be issued. With possible new regulations regarding silica, having a dust vacuum system that can operate without interruption will become crucial in order to maintain lower PEL ratings and minimize the cost of these new regulations.

When it comes to dust containment not all vacuum systems are equal. Some (such as the CDCLarue vacuum systems with Pulse-Bac technology) use techniques to prevent the filters from facing with dust and clogging during operation. This reduces dust migration on the filter while maintaining the PEL for extended periods of use.

Clogged vacuum filters are the main reason contractors exceed PEL ratings. For years the use of conventional vacuum systems has been the norm with the same outcome, filters face with dust then clog and the vacuum begins to lose suction power and fill the jobsite with hazardous dust. It is a flaw found in all conventional vacuums systems. Some vacuum systems overcome this flaw and are able to maintain safe PEL ratings for extended periods of use. This is achieved because the filters do not clog during operation. For example, the Pulse-Bac systems pulses the filter to allow suction power (flow rate and lift) to remain constant for as long as the vacuum is in operation. This keeps the user in compliance with regulations without giving up productivity and profits.

Preventing the filters from clogging is crucial if you want to maintain a safe PEL rating. Vacuums operate by pulling air through the filter via a motor. Air is then exhausted by the motor back out into the work space. Conventional vacuums deliver constant vacuum pressure on the filters via this motor. This constant pressure is what causes the filter to clog. Eventually the pressure from the vacuum motor will pull dust through the filter causing dust to migrate through and into the vacuum motor (dust migration). Once this migration occurs the filters need to be changed or dust will continue to be exhausted from the vacuum and into the air. This can cause the dust levels to exceed the Permissible Exposure Limit and reach unhealthy levels.

Conventional vacuums are inefficient at stopping the filter from clogging. They rely on the user to stop working and either shake the filter clean, trigger a compressor for blow back, or simply replace the filter to keep working.

Paying an employee to stop and clean filters can cost you plenty. This is one of the many hidden costs associated with conventional vacuums. These vacuums start off capturing dust but after a few minutes filters clog and the jobsite becomes foggy with dust. By the time it is noticed it is often too late.

The human eye can see dust around 40 microns but the average silica particle is 3 microns. By the time you see it in the air, you have been breathing it. This potentially harmful failure occurs because the vacuum no longer has enough air flow (cubic feet/minute, CFM) to capture the dust being generated by the tool or equipment attached to it.

The technology in the CDC Larue vacuums virtually stops dust migration by continually pulsing dust and debris off the filter. This process prolongs the filter life and reduces cost to maintain the vacuum lowering the cost of operation and increasing productivity.

The patented filters capture dust particles as small as 0.12 microns putting the systems at the cutting edge of vacuum technology. This is the only brand of vacuum equipment with a fully automatic filter cleaning system that requires no shakers, compressors, or buttons to push. Just turn it on and go to work. The vacuum does the rest.

Chris McCutchen is vice president of sales and marketing at CDCLarue Industries, Inc., Tulsa Okla. For more information on these products, visit