By Safety Management Group
There are many hazards around workplaces that are all too easy to ignore, because they seem to be benign. One of those is the use of vacuum. Workers may encounter vacuums both in the permanently installed systems that are used in many healthcare-related and industrial environments, and in the devices that are used to remove dust and debris from worksites. In this article, we’ll examine the hazards and safe practices associated with both types.
Vacuum Systems
Hospitals, pharmaceutical production facilities, and laboratories are all examples of the types of businesses that may use built-in vacuum systems when performing normal tasks. Typically, these systems involve vacuum lines from multiple locations that are drawn to a central unit.
Workers may underestimate the hazards associated with vacuum systems. After all, it’s just a matter of air moving away from them — much like the suction involved in using a vacuum cleaner at home. But vacuum systems in these settings tend to be far more powerful. When something goes wrong, the results can include shattering and flying glass, chemical splatters, and even combustion.
The dangers can be even more substantial. For example, two plumbers working in a California university laboratory in 2001 were trying to solder a fitting on a copper vacuum line. The line burst open, causing serious injuries. Investigators detected traces of acetate and copper perchlorate in the line, which evidently combined and then exploded from the heat of the soldering torch.
That’s why workers who use or work around vacuum systems need to be cognizant of the potential hazards. Depending upon the nature of their tasks, they may need to wear face shields, safety glasses, or other types of personal protective equipment to protect them from fragments or chemical splatters. Workers should also avoid striking equipment attached the vacuum line or causing unnecessary pressure on components.
If the vacuum will be used near liquids such as solvents or corrosive gases, a cold trap should be installed to prevent those materials from being drawn into the pump. The cold trap must be large enough and have a temperature that’s low enough to properly condense any vapors that may be encountered. When vacuum equipment is being used, the cold trap should be checked regularly to ensure that it isn’t blocked. And, if condensate somehow travels past the cold trap and enters the vacuum pump, that pump should be replaced.
Industrial Vacuums
Dust and debris are normal byproducts of most industrial activity. At the very least, they can irritate workers’ eyes and noses and cause problems with the lungs. Some dust and debris may even be toxic. And dust and debris that are made up of combustible material present an even more serious hazard: the potential for explosions.
Vacuum equipment is engineered to remove dust and debris from jobsites, and then to store it safely while waiting for disposal. While vacuums made for industrial settings may look a lot like the shop-vac in your home’s garage or basement, they are designed very differently.
Explosions. Many industrial vacuums are engineered to ensure that they will not trigger explosions when handling combustible materials. For explosions to occur, five conditions must be present. The material being collected must be combustible, it must be stored in a closed container (such as the interior of a vacuum), there must be enough oxygen present to allow combustion, the material must be dispersed within the container, and there must be a spark or other ignition source. When designing explosion-proof vacuums, engineers seek to eliminate one or more of those conditions. For example, they use special materials that do not generate sparks, such as hoses that do not create static electricity.
Filtration. To prevent dust and contaminants from being expelled in exhaust air, many vacuums are equipped with highly efficient filters. The two most common types are HEPA-certified (High Efficiency Particulate Air), which will remove 99.97 percent of particles larger than 0.3 microns in size, and ULPA (Ultra Low Penetration Air), which stop 99.99 percent of particles as small as 0.12 microns in size.
Other types of filters meet the special needs of specific applications. As an example, vacuums for use on jobsites where sticky waste materials may be present often use filters that have a PTFE (Teflon) non-stick surface.
Collection. Removing dust and debris from the worksite is only the first role a vacuum must serve. The materials it captures must also be collected and stored in a way that protects workers, and that allows for safe disposal. Most vacuums used with hazardous materials have some type of disposable container to minimize the potential of contact. Depending upon the application and need, choices may include everything from simple paper bags, to paper bags with electrostatic properties, to polyliners. Sophisticated systems used in medical research and pharmaceutical applications may use sealed plastic containers.
Supervision issues
Identifying and having the correct type of vacuum system for the nature of the hazard is only part of providing protection to employees. Supervisors need to ensure that employees understand the hazard and follow all of the steps involved in minimizing it. Depending upon the type of material, there may be a preferred way to clean it, and specific types of personal protective equipment may be necessary. By ensuring that workers are in compliance with every aspect of the process, supervisors will ensure that the equipment is serving its purpose effectively.