Inhalation Rates for Risk Assessments Involving Construction Workers in Canada

ABSTRACT

A Monte Carlo simulation was performed to generate probability density distributions describing hourly inhalation rates of male and female construction workers. Ranges of oxygen uptake and ventilation rates reported in the literature for various construction trades were manipulated in a simulation to generate hourly inhalation rates for male construction workers. The resulting inhalation rates can be represented by a log normal distribution with mean ± standard deviation of 1.40 ± 0.51 m³/h. Hourly inhalation rates for female construction workers were scaled from those of their male counterparts using relative awake-time inhalation rates of men and women of the general public. Female construction workers' inhalation rates can be represented by a log normal distribution with a mean ± standard deviation of 1.25 ± 0.66 m³/h. If the nature of the work is well understood, male and female construction workers' hourly inhalation rates can be scaled according to the construction trade. Construction trade-specific scaling factors were developed and range from 0.78 for electricians to 1.11 for ironworkers.

Key Words:

• construction workers
• hourly inhalation rates
• time-activity-ventilation
• human exposure factors
• probability density functions

ACKNOWLEDGMENTS

The authors gratefully acknowledge Health Canada, Contaminated Sites Division, which funded development of the inhalation PDFs for construction workers and provided helpful comments and critique.

Notes

*Allan et al. (2007);

**Williams (2001).

*From Abdelhamid and Everett (2002).

** Coefficients of variation are included in this table for convenience but were not used in the development of the recommended scaling factors.