Machinists may work alone or with tool programmers to check new programs to ensure that machinery will function properly and the output will meet specifications. Because a problem with the program could damage the costly machinery and cutting tools, computer simulations may be used instead of a trial run to check the program. If errors are found, the program must be changed and retested until the problem is resolved. In addition, growing connectivity between computer-aided design software and CNC machine tools is raising productivity by automatically translating designs into instructions which are understood by the computer controller on the machine tool. These new CAM technologies enable programs to be more easily modified for use on other jobs with similar specifications, thereby reducing the time and effort.
Most machine shops are well lit and ventilated.
Nevertheless, working around high-speed machine tools presents certain dangers, and workers must follow safety precautions. Machinists must wear protective equipment such as safety glasses to shield against bits of flying metal and earplugs to protect against machinery noise. They must also exercise caution when handling hazardous coolants and lubricants. The job requires stamina because machinists stand most of the day and may lift moderately heavy workpieces. Some tool programmers work in offices that are near, but separate from, the shop floor.