Although neither OSHA’s occupational noise exposure regulation nor the powered industrial truck standard address the use of headphones in the workplace, OSHA has issued Letters of Interpretations that do not recommend the practice. A major concern for a forklift operator is that the operator will increase the volume of the headphones high enough to drown out workplace noise. This can result in the operator not hearing alarms and shouted warnings, as well as exposure to noise levels that exceed the OSHA permissible exposure levels.