Industrial Vaccuum Cleaners: They're Not Your Mother's Cleaning Tools

The relative cost of even the most elaborate central vacuum system is minute compared to the loss of life that occurs from secondary explosions or the fines levied against a company that fails to proactively protect their workers.

Although the majority of companies aren't in willful violation of the standards, a lack of understanding of housekeeping standards and misconception of the relatively low cost of vacuum systems prevail in the industry. Often times, the addition of industrial vacuum cleaners to the housekeeping routine produces additional cost benefits in terms of increased production, reclamation or wage savings.

APPLYING HOUSEKEEPING STANDARDS

The proper selection of an industrial vacuum cleaning system is based primarily on the application. In some cases, small air and electric-powered drum- style units will suffice, while others require a central large electric and diesel powered units for multiple users and filtration systems capable of capturing particles that are invisible to the naked eye. Often, users may assume they need a custom, one-of-a-kind solution when their application actually calls for a standard, pre-engineered product.

Some applications require sophisticated customized vacuum cleaner installations. For other applications, compact, off-the-shelf vacuum systems are perfectly adequate when replacing crude or unnecessarily hazardous cleaning methods, such as the use of compressed air hoses for blowing debris.

H.R. 849 would compel OSHA to issue an interim and final combustible dust standard to help prevent deadly explosions. Many proponents want OSHA to mandate combustible dust safety through the use of NFPA codes, and companies are urged to proactively follow these guidelines when setting up a good housekeeping program.

The NFPA standards that the OSHA Hazard Alert refers to being applicable to dust explosion hazards are NFPA 654, 61,484,664 and 655. In brief, the standards call for establishing regular cleaning frequencies to minimize dust accumulation on walls, floors and horizontal surfaces such as equipment ledges, above suspended ceilings and other concealed surfaces. The standards further state that vigorous sweeping or blowing down with steam or compressed air only should take place after the area or equipment has been vacuumed, due to the creation of dust clouds by the other methods.

Standards also call for vacuum cleaners to be specified for use in Class II hazardous locations or be a fixed pipe suction system with a remotely located exhauster and dust collector. When flammable gasses are present, vacuum cleaners need to be listed for Class I and Class II hazardous locations.

NFPA 61 for food and agricultural processing plants has somewhat reduced precautions compared to the previously listed standards. NFPA 484 for combustible metals requires that dust and particles be cleaned with non-conductive scoops or soft, natural brushes or brooms before the dust is vacuumed. In addition, vacuums are suggested to pick up dust that is too small to be picked up with brushes. Blowing combustible metal dust with air compressors is not permitted.

For cleanup of truly explosive materials such as gunpowder, rocket propellant, sodium azide and aluminum powder, which can explode if collected in dry form, a submerged recovery vacuum cleaner is available and designed specifically to pick up explosive powders safely. The explosive or hazardous material is submerged under fluid to render it inert. The unique design includes not only a high liquid level safety shut-off, but also a low liquid safety shutoff to prevent vacuum operation if insufficient liquid is in the drum.

HOUSEKEEPING FOR FINE POWDERS AND CHEMICALS

Industrial vacuum cleaner experts are skilled at designing systems around a company's particular needs. For instance, a custom job shop fabricator faced potential flammability issues because they couldn't adequately sweep the fine powder coating residue from the floor, lights, booth walls and components of their facility. Shop-type vacuums they had been using posed a static electric shock to the workers and productivity suffered. Not only did they have to vacuum, but they also had to clean by hand using wet rags to prepare booths for the next powder-coating job.

To eliminate any shock, fire or explosion hazard associated with electric or engine driven units, the fabricator installed a Venturi compressed air-powered vacuum with antisparking vacuum inlets and grounding lugs; static conductivity from end to end, including a static conductive hose with internal ground wire; and grounded end cuffs, which prevent static build up.

To further reduce sparking danger, static-conductive filters rated 99.9 percent efficient at one micron were used, which virtually eliminated any fine particle discharge from the vacuum's exhaust back into the work area. This helped to create healthful, productive breathing conditions in the workplace.

Furthermore, a unique pulse jet filter cleaning system on all the company's air vacs not only increased color changes in the powder coating industry but also ensured high vacuum efficiency while virtually eliminating clogged or “blinded” filters. By simply pushing a button on the air vac, the operator can backwash the filter with compressed air instead of taking the vacuum apart to clean the filter by hand.

For many manufacturers and processors, industrial vacuum cleaners now are being completely integrated into production and process systems, and are quickly becoming a key component of critical strategic issues that range from productivity to environmental safety and worker health.

Regardless of the political aspects of any combustible dust legislation, companies need to be proactive in implementing standard housekeeping practices. Since 2006, there have been nearly 100 reported dust fires and explosions, and no company executive wants to be responsible for allowing the makeup of a catastrophic explosion.

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Lisa Zocco is a technical writer based in Long Beach, Calif., specializing in industrial manufacturing and B-to-B industries. To learn more about industrial vacuum cleaning systems for production lines and other dust-intensive areas, visit http://www.vac-u-max.com.