The TLV for carbon monoxide is 25 ppm according to the Ministry of Labour in Ontario. Consider the following example:

1) A mechanic in an automotive repair shop is exposed to the following carbon monoxide levels over an 8 hour shift.

a. 3 hours @ 28 ppm/hr

b. 4 hours @ 42 ppm/hr

c. 1 hour @ 22 ppm/hr

> Is the worker over-exposed during the duration of the work shift? (To complete the calculation, add up the doses for every hour of the shift and divide by 8 hours to determine average exposure. Show your work for full marks - round your answers to 2 decimal places).

> What is the primary concept of hazard recognition and the hierarchy of hazard control?

> Going through the Hazard Control Hierarchy - explain how the types of interventions in the hierarchy might be applied to this example to provide potential solutions.