The finding is from a study of 627 current or former smokers surveyed as part of the National Survey of Midlife Development in the United States.
Researchers asked respondents whether they worked with anyone who smoked in their immediate work area or lived with a smoker.
Having both the presence of smokers in the workplace and in the home significantly increased the odds that a respondent was also a current smoker.
Working with a smoker was linked to almost three times greater odds of smoking, whereas living with a smoker was linked to more than six-fold greater odds of smoking.
For those people living with a smoker, their smoking was unrelated to whether or not their work colleagues smoked.
"Our findings suggest that worksite smoking interventions could be made more effective if they included a focus on educating workers' families about the health effects of smoking and the benefits of home smoking bans," lead author Carole K. Holahan, Ph.D., professor of kinesiology and health education at the University of Texas, Austin, said.
The study in the American Journal of Health Promotion.