Industrial Hygiene in Construction

As common as it sounds, falls in construction are still the #1 killer.

Go to www.osha.gov/stopfalls

This site has good information, reminders, training, and resources.

I love the show, “Dirty Jobs” with Mike Rowe. I find it fascinating what people are willing to do for work. Many of the jobs on the show have a true element of danger. Either a pinch point, an animal bite/kick, struck-by, heat/cold extreme, confined space, etc.

Did you ever consider what makes something hazardous?

My “deep thought for today” (thanks Jack Handy) is that education and training can make a job less hazardous. If you know how to do it right, and you know the risk, it doesn’t seem as dangerous anymore. The risk is there, but you know how to handle it, so the “hazard” seems to fade. This week I’ve given two separate asbestos classes to two different employers. At the beginning the employees were genuinely concerned about the hazards. By the end, they looked a lot more comfortable about upcoming project.

Is it any surprise that the HazCom standard is the most OSHA cited rule year over year?

So, keep up the training! Educate the employees on the dangers.

When performing air monitoring it can be useful to take multiple samples on the same individual throughout the day. Here are some reasons to change out the filters:

• build up of dust on filter – can cause overloading
• break-out the exposure data. Morning versus afternoon, or by job tasks, or the physical area the employee is working in, controls vs. no-controls, etc.
• if you question the employees motives. If you think the employee might skew the results, multiple samples might give you better control- or at least tell you if one is way-out-of-line.

Once you have your data results, how do you combine them?

If you’re taking particulate (dust, lead, cadmium, silica, etc) and you have the concentrations (from the lab) here is what to do.

1. note the time (in minutes!) and the concentration results (mg/m3, ug/m3, etc) for each sample
2. multiply the time and concentration for each – then add each number together
3. finally, divide the above number by the total number of minutes sampled. This is your time weighted average (TWA).

Simple?! Yes. …And it’s really easy to make a mistake too. Check your math, and then eyeball the results and see if they make sense logically.

Here’s an example:

Andrew took three samples during one shift while Shelley was rivet busting through leaded paint. The first sample (118 minutes) was reported as 6.8 ug/m3 of lead, the second was for 245 minutes and had a concentration of 18 ug/m3. The last sample was taken for 88 minutes and was reported a level of 29 ug/m3. The overall results is 17.2 ug/m3 for the total time sampled. (Side: if you sampled for their entire exposure, and they worked longer hours, you could add those hours (assuming zero exposure) into the final time-in step three)

See the math below:

Do you measuring dust on your project/ workplace? If you are a safety professional and you are self-performing this type of sampling here are some tips.

• Measure for the full shift (including prep and clean up) – clean up can be the worst
• Depending on the type of dust, you might need to measure by either respirable, or inhalable (IOM) methodology.  -more on this at a later date
• Watch the dust filter build-up. You might want to change the filter out so as not to overload the cassette. Especially during clean-up.
  
• Have you checked for metals? Many types of dust can contain metals. Ask the laboratory for assistance.
• Consider the placement of the sampling filter. Do you want it downwind? On the collar? Is it on the best employee for sampling?
• Do you perform an area sample? These are not usually recommended, but sometimes they can give you great information.
• Information. Capture all the information that might be important to this sampling. Time, humidity, temperature, controls (or lack of), open doors/windows, employee practices, etc.