7.C.8.4.3 Cutting and Puncturing Tools
Hand injuries are the most frequently encountered injuries in laboratories. Many of these injuries can be prevented by keeping all sharp and puncturing devices fully protected, avoiding the use of razor blades as cutting tools, and using utility knives that have a spring-loaded guard that covers the blade. Appropriate cutting techniques and the use of the proper or specialized tools should also be considered. Dispose of razor blades, syringe needles, suture needles, and other sharp objects or instruments carefully in designated receptacles rather than throwing them into the trash bin unprotected. (See Chapter 4, section 4.E.9.)
Minimize glass cuts by use of correct procedures (e.g., the procedure for inserting glass tubing into rubber stoppers and tubing, which is taught in introductory laboratories), through appropriate use of protective equipment, and by careful attention to manipulation. Protective equipment is not fail-safe and should not be relied on to prevent cutting injuries. A variety of adapters are available that render glass tubing and rubber stoppers largely obsolete. Technique is also important. In the case of a slip or a break, the resulting motion should not be in the direction of the person. For example, perform cutting operations with the cutting motion moving away from the body.
7.C.8.4.4 Noise Extremes
Any laboratory operation that exposes trained laboratory personnel to a significant noise source of 85 decibels or greater for an 8-hour average duration should have a hearing conservation program to protect from excessive exposure. Consult an audiologist or industrial hygienist to determine the need for such a program and to provide assistance in developing one.
7.C.8.4.5 Slips, Trips, and Falls
The risks of slips, trips, falls, and collisions between persons and objects are reduced by cleaning up liquid or solid spills immediately, keeping doors and drawers closed and passageways clear of obstructions, providing step stools, ladders, and lifts to reach high areas, and walking along corridors and on stairways at a deliberate pace. Floors that are likely to be wet, for example around ice, dry ice, or liquid nitrogen dispensers, should be slip resistant or have a slip-resistant floor covering. Make paper towel dispensers available for wiping up drops or small puddles as soon as they form. Avoid clutter in the laboratory to reduce the temptation to “make space” on the bench by storing items on the floor, which can create a trip hazard.
7.C.8.4.6 Ergonomics and Lifting
Both standing and sitting in a static posture and making repeated motions have been shown to cause a variety of musculoskeletal problems. Problems due to poor ergonomics include eyestrain, stiff and sore back, leg discomfort, and hand and arm injuries. Each situation needs to be evaluated individually. However, personnel who spend significant time working on video display terminals should use furniture appropriate for these tasks, proper posture, and perhaps special eyeglasses. Also, people who use the same tools and hand motions for extended periods of time should take breaks at appropriate intervals to help prevent injuries.
Lifting injuries are one of the more common types of injuries for trained laboratory personnel. The weight of the item to be lifted is a factor, but it is only one of several. The shape and size of an object as well as the lifting posture and the frequency of lifting are also key factors in determining the risks of lifting. The National Institute for Occupational Safety and Health (NIOSH) has developed a guide that should be consulted to help determine lifting safety (Waters et al., 1994). Personnel who are at risk for lifting injuries should receive periodic training.
7.D.1 Compressed Gas Cylinders
Precautions are necessary for handling the various types of compressed gases, the cylinders that contain them, the regulators used to control their delivery pressure, the piping used to confine them during flow, and the vessels in which they are ultimately used. Regular inventories of cylinders and checks of their integrity with prompt disposal of those no longer in use are important. (See Chapter 5, section 5.E.6 for information on storing gas cylinders, and Chapter 6, section 6.H, for discussion of the chemical hazards of gases.)
A compressed gas is defined as a material in a container with an absolute pressure greater than 276 kPa, or 40 psi at 21 °C or an absolute pressure greater than 717 kPa (104 psi) at 54 °C, or both, or any liquid flammable material having a Reid vapor pressure greater than 276 kPa (40 psi) at 38 °C. The U.S. Department of Transportation (DOT) has established codes that specify the materials to be used for the construction and the capacities, test procedures, and service pressures of the cylinders in which compressed gases are transported. However, regardless of the pressure rating of the cylinder, the physical state of the material within it determines the pressure of the gas. For example, liquefied gases such as propane and ammonia exert their own vapor pressure as long as liquid remains in the cylinder and the critical temperature is not exceeded.
Prudent procedures for the use of compressed gas cylinders in the laboratory include attention to appropriate purchase, especially selecting the smallest cylinder compatible with the need, as well as proper transportation and storage, identification of contents,