Using high-pressure air or gases to blow off or dry parts can create embolisms—small bubbles in the bloodstream that cause blockages—if the nozzle comes in contact with your body. The law requires that you use special nozzles designed to prevent this risk. Alternatively, the gas pressure may be limited to allow gas to be used safely to clean and dry parts. The Laboratory Safety Advocate’s office has developed an inexpensive kit to help. Learn more in High Pressure Blow-Off Gas.
Tag: physical-pressure
Related specifically to pressure hazards, including compressed gases and vacuum
Protect your face with a face shield
When a hazard involves a lot of energy or aggressive chemicals, your face may be at risk as well as your eyes. Also, Z87.1 or Z87.1+ rated eye protection may not be adequate to protect your eyes, so additional protection might be prudent. If you could injure your face in an accident, use a face shield to protect your face – learn more in High energy facial protection.
Protect your eyes from physical hazards
Physical hazards require eye protection designed for physical hazards. Always wear safety glasses or goggles when working with manual or power tools that may produce small particles (e.g., sanding, milling, cutting, hammering, scraping, etc.); working with tools that can generate droplets or a strong (>20psi) fluidstream, whether the fluid is air, water, or something else; processes producing lots of dust or other particles in the air (e.g., blowing leaves or snow from the sidewalk). Learn more in Physical hazard eye protection.
Is your plastic gas tubing an over-inflated balloon?
Many labs use compressed gases, and often we use pressure regulators to step down the 2000-3000 psi in the cylinder to the use pressure. If the regulator can produce more than about 30 psi outlet, your plastic tubing might be in danger of rupture. Read more about how to fix this without buying a new $500 regulator in How to prevent plastic tubing rupture.
Incident report: Tank damage, Krieger Hall, May 2014
While performing experiments in a large water tank, a researcher placed an incandescent spotlight in front of a 2-inch thick Plexiglas observation window. During the experiments, the lamp slipped and came to rest against the window surface. The window melted one-third of the way through, compromising its mechanical integrity.
Learn more about this incident in Incident tank damage Krieger May2014.
Incident report: Regulator overpressure, Ames Hall, Feb 2014
A researcher was attempting to change the acetylene pressure on an atomic absorption spectrometer by adjusting the pressure regulator. He inadvertently set the pressure well above 15psig, despite the signs (and the red markings on the regulator) warning not to do so. When acetylene pressure exceeds 15psi, the gas can liquefy; in this state, acetylene can suddenly and explosively polymerize. Fortunately, this did not occur, although the regulator was ruined from overpressurization.
Learn more about this incident and its implications in Incident Ames Feb2014.
Lab air can kill you
Equipment, experiments, and people often get dirty—a lab bench covered with cement dust, a drill press clogged with metal shavings, wet glassware that needs drying, or even a researcher covered with sawdust after cutting a wooden part. Some people look to the compressed air tap or cylinder in the lab as a quick way to clean off.
Did you know this can kill?
Even a relatively low-pressure stream of air can propel chips, dust, and parts through the air at high velocity; the flow from a 20psi air line can be supersonic. If this material strikes someone, it can cause serious injury. If the injury is to the eye, the victim may be permanently blinded.
Even worse, a few tens of psi pressure can easily inject air beneath the skin, inflating body parts like balloons—and causing excruciating pain. If air reaches the bloodstream, it can cause air embolisms—blockages in narrow blood vessels—as well as clots & ruptures in vital areas such as the brain. Uncontrolled air injection can be deadly.
Read tips for safely handling compressed air at Compressed air misuse.
OSHA Compressed gases and equipment information
OSHA maintains a page with laws, regulations, good practices, and links to further information, all covering work with compressed gases and equipment.