occupational hygiene


Confession: I missed the assessment of this hazard the first time.

Awhile back I performed air sampling during aluminum welding. The welders were cordial and let me crawl over their welding equipment, poke around old boxes of wire and metal stock. I did not think there were any “real” hazards. We did find some airborne levels of various metals. From the picture can you tell who did the most welding?

welding mce

After I had performed the sampling and the report was sent, I was asked if I had checked for ozone (O3)? I admitted I hadn’t and asked if it was an issue? Well, apparently it is (or rather, might be).

I went back to the shop, begged for another chance, and performed ozone sampling. It wasn’t difficult, but eating crow was the hardest part.

More information on the subject can be found at: NIOSHUK- HSE. Ozone is formed when the UV radiation hits oxygen. The ACGIH TLV is variable (see table below)ozone acgih, and the OSHA PEL is 0.1 ppm.

Health: Ozone, O3, can cause lots of different respiratory illnesses. These can include a decrease in lung function, aggravation of asthma, throat irritation/cough, chest pain, shortness of breath, inflammation of lungs, and a higher susceptibility to respiratory illnesses. ACGIH classifies it as an A4, or not a suspected carcinogen.

Luckily the results were found to be non-detectable (“IH talk” for none-found). Which only means I didn’t find it, not that it is not there. I sampled for a long time (530 minutes) because they were working 10 hour shifts. But, they only welded for a total of approximately 1.5 hours during that time.

If welders are in a confined area, or a small space with limited ventilation, the results might be significantly different.

 

I am the current chairperson of the AIHA Consultant’s Special Interest Group (Consult SIG). We conducted a survey and asked the AIHA membership of industrial hygiene consultants what their needs are, and how, as a group, we could help them. A summary of the survey result findings was just published in the November, 2014 AIHA’s, The Synergist, titled, “What IH Consultants Want“.  

We didn’t make the front page. But hey!, we weren’t on the last page either (second page to back, ha).

Nov 2014 Synergist

I cannot publish it here due to copyright infringement, but email me if you want information on the results of the survey.

Instead of explaining how to calculate safe levels of chemical mixtures, this will be a reminder.

The American Conference of Governmental Industrial Hygienists (ACGIH) in their Threshold Limit Values (2014), has an excellent explanation of how to calculate a safe level of exposure. However, in summary, if separate chemicals have the same health effects (effect the body in the same way), they may do three things:

  1. Additivity – the sum of their exposure & health effect is A+B. More on this below.
  2. Synergy – the sum of their exposure is MORE than A+B. This is bad, and hard to calculate.
    • Similar in principle to smoking and asbestos. If you smoke and have asbestos exposure, you are worse than just the additive.
  3. Antagonism – the mixed chemicals cancel each other out. It usually never works this way.
    • But, as a terrible example, it would be like acid rain dissolving styrofoam. (I don’t think that’s true, BTW)

Back to Additive (Additivity):additive

If two chemicals (or more) in a mixture have similar health effects (central nervous system, or effect the kidneys, for example), then, until you know otherwise, you should assume they have additive effects. Have your favorite Industrial Hygienist use your air monitoring data to calculate the additive effects using the ACGIH Additive Mixture Formula.

This is useful for combining both full shift air monitoring data, short term, and ceiling exposures. Extreme caution should be used if the chemicals are carcinogenic (as low as reasonably achievable (ALARA) is best here), or if they are complex mixtures (diesel exhaust).

It’s a bit confusing, but worthy of reminding ourselves of chemical mixtures.

It is officially summer and construction road crews & roofing is in full swing. Some projects require the use and application of coal tar pitch. Not only is it stinky, it is is hazardous.

Here’s some info:

  • Uses
    • Roofing
    • Asphalt seal coating
    • Pharmaceutical treatment for psoriasis (scalp/skin condition)
    • Graphite industry (in the production of graphite)
  • General
    • Coal tar pitch is actually a make-up of a bunch of different substances (maybe even 10,000 of them)
    • Contains lots of polycyclic aromatic hydrocarbons (PAHs) and other chemicals including: benzene, pyrene, benzo(a)pyrene, phenanthrene, anthracene
  • Exposure
    • can be exposed by inhalation, ingestion (is this likely?), or exposure to skin, eyes
    • considered a carcinogen if the product contains more than 5% of coal tar
    • cancers include: skin, scrotal, lungs, bladder, kidney & digestive
    • increases your sensitivity to sunlight (easier to sunburn)
  • Safety
    • Pick a sealant/coating that does not contain coal tar. A list of some can be found here.
    • Avoid inhalation & skin/eye contact
    • Train your employees. A sample safety SDS (MSDS) can be found here.
    • Wear the correct PPE.
    • Air sample to determine exposures. OSHA has a method (58).
  • Resources

asphalt

This question gets asked a lot, and in many different ways. Such as:asbestos iron

  • Will I get hurt if I touch asbestos? (aka: How long can I be exposed?)
  • What if I have done siding removal/cutting pipe/removed TSI (etc) on an asbestos containing product, am I safe?
  • If I am only doing going to do touch asbestos for 20 minutes (or ___ time), will I still be in compliance?
  • I am disturbing less than 3 square feet of asbestos, I can do this legally, right?

The answer is:   it depends.

Or, an alternative answer: if you think you are disturbing asbestos; you’d better verify (by performing an air sample).

Nowadays there is no excuse for exposing employees, tenants, neighbors to asbestos. And, really, if you are working with asbestos, you need to be extra diligent to inform everyone about the hazard. The worst situation isn’t from a single exposure to asbestos, or an OSHA fine. The worst situation is this:  when you don’t pre-plan, and then verify your exposure levels. Because, someone will make up a worst case scenario, and at that point, you are already behind.

 

 

Can we measure an exposure accurately with just one sample? (statistically, no.) Also consider: Can we measure a “worst case” scenario and be OK for the rest of the project? (again, hypothetical question)

There was a blog post, here by Mike Jayjock, which reminded me of how silly our data points (aka industrial hygiene sample results) are in the big picture of statistics.  I’m slowly reading a book titled, “Control Banding” by David Zalk who is with Lawrence Livermore National Labs. The CDC also has a section on control banding here.

Another side of this is a common practice we all perform called Risk Analysis. There is much on the subject, but essentially it’s similar to triage at an emergency room. What is the easiest, best thing you can do: given what you have available and what you are able to muster?safety triangle

Too often (myself included) we perform air monitoring for a specific situation and use that information as the gospel-truth. Well, this might be like living in the United States and never traveling. We meet a very nice person from the Ukraine. They seem very typical Eastern European and have a thick accent, but are they really like everyone in Russia? Is this person typical? Are they exactly like every other person from Russia?

This type of stereotyping is the same as taking one sample and drawing conclusions about all exposures. You might be right, BUT…you might be wrong.

There is a fun app you can download called, IH DIG by Adam Geitgey (Apple & Android).  This app illustrates the importance of using statistical tools, rather than guessing. (It’s a game)

Sorry I do not have many answers in this post, just a lot of questions.

Let’s clarify: You are a working adult. You are feeling symptoms (of some sort). And, you think it’s from something your exposed to while at work (in construction). This could include, but will not, the flu-bug. Below is a list of the most common construction illnesses.

Most Common Construction Illnesses:

  1. Upper respiratory
    • could be from silica, drywall, dust, asbestos, nuisance dust, chemicals (I won’t even try to list all of them)
  2. Skin (dermal, dermatitis) damage –
    • From: concrete, abrasion, chemicals
  3. Eyes
    • mostly from things that get into the eye.
  4. Cumulative trauma (ergonomics) or inflammation
    • repetitive motion, over a day hurts, imagine this for years
  5. Burn (heat or chemicals)
    • Usually around hot work like welding, but this can occur when using certian chemicals
  6. Hearing loss
    • cumulative trama to the ears when exposure is above about 85 decibels for any extended period of time.
  7. Poisoning– General or systemic
    • From: poison ivy, stinging needles, dog bites, bees, etc.

This list may vary depending on many things including what type of construction you are in; GC, heavy, civil, specialty, etc.  I put this list together to get a picture of where we see illnesses. However, as previously mentioned, and, everyone knows, the FOCUS FOUR is really where most injuries occur in construction.

We have seen the most prevention of illness due to one single device:

back supportthe back support.   ha. just kidding, of course.

This has to be one of the coolest types of cutting. Raw obliteration of metal.

As you know, hexavalent chromium (Cr6) is generated when the metal, chromium, is heated. Cutting this metal with a plasma torch is an easy way to heat it up quickly.  We performed air monitoring on one employee performing plasma cutting on #304 stainless. Luckily the employee was wearing a 1/2 face tight fitting respirator (and skin protection due to the body readily absorbing Cr6) and we found exposures at 36% of the exposure limits (they were within the acceptable limits). This employee was able to stand away from the cutting due to the machine he was using. He did not do this task all day and no engineering controls (ventilation) was used. 

****Caveat: Please do your own air sampling. Conditions and environment may not be similar to your environment, and they can change rapidly. One sampling event rarely indicates all conditions. We’re talking about people’s health!****Keep in mind welding safety

plasma cutting

And a close up of the cutting machine without the motor & tracks:

cutting bevel

People are inspiring. Starting in 2014, I would like to profile prominent professionals in the health, safety and construction industry.

The idea originally came from a publication  called, The Synergist,  published by the AIHA. At the back of their magazine they introduce someone in the industry. I have always enjoyed hearing about how others got into this field and where their paths have taken them. Unfortunately, this publication is (mostly) only for people in industrial hygiene. Which (IMO) does little to promote the profession to others outside of it.

 

Illa Gilbert-Jones, CIH, CSPIlla 2014

How did you get started in IH?
I was in the Masters program at the University of Washington and started out with an emphasis on toxicology. I noticed that those in industrial hygiene in the class before me we’re getting job offers so I decided to also complete the industrial hygiene courses.

What is your background?
My career started at Boeing Company as a safety administrator just before completing my masters. From there I have worked as an industrial hygienist for Bayer Corporation Product Safety for the chemical business, primarily isocyanates. I also worked in their Corporate Safety/Industrial Hygiene group before moving to Phoenix where I worked for Phelps Dodge Mining Company as the Corporate Occupational Health Manager. Although a copper mining company, Phelps Dodge also had smelters, refineries, copper magnet wire, and carbon black facilities with classic industrial hygiene issues-heavy metal fumes. After leaving Phelps Dodge, I did a short stint with Clayton Environmental in California before taking a position with a paint manufacturing/distribution as the Security, Safety, Health & Environmental Manager. After a few years in California, we returned to the Northwest where I worked for SAIF Corporation for over 7 years as a safety management consultant.

You are starting a new position, can you tell us what you will be doing?
On January 1st I accepted the position as Program Administrator for Oregon Fatality Assessment & Control Evaluation (OR-FACE). OR-FACE operates under a NIOSH grant. The program is research based and designed to identify and study fatal occupational injuries. The goal of the FACE program is to prevent occupational fatalities by identifying and investigating work situations at high risk for injury and then formulating and disseminating prevention strategies to those who can intervene in the workplace. More specifically,
• Identify traumatic occupational fatalities through a statewide surveillance network
• Investigate selected traumatic occupational fatalities
• Have a multidisciplinary team analyze the surveillance and investigation data
• Develop and disseminate prevention strategies for these injuries
• Collaborate with other states and NIOSH to develop prevention strategies to decrease the rate of occupational injuries and fatalities

What has been the most satisfying aspect of the field?
Similar to all occupational safety & health professionals, satisfaction is in observing and experiencing improvements in work conditions by reducing risk of contaminant and physical exposures. It is especially satisfying after struggling time-after-time to influence decision makers and then a breakthrough finally occurs and they become safety advocates.

What is the most fun part?

Developing relationships with those as passionate about injury/illness prevention and in giving back to the profession by mentoring those new to the field.

What is the challenging part?

The realization that the job is never done. Serious injuries and fatalities continue to happen. For occupational illnesses from chronic exposure it is very difficult to influence change today for a negative outcome in the distant future.

What advice do you have for those getting started?

Never be satisfied with small changes, be persistent and try all options in pursuing what you believe to be right. Always look for opportunities to increase yours and others in subject knowledge. Additionally, expand your expertise into areas that are normally grouped with industrial hygiene, e.g., safety, risk management, environmental.

What are your hobbies and outside interests?

I try to please my artistic side by learning and writing calligraphy. On the physical side, I try to go to water aerobics regularly, bicycling, and also use a wrist fit-bit to track my daily steps.

What do you see for the future of IH?

Practicing industrial hygiene creates skills for investigating and understanding several layers of causes. These skills enable an H&S professional to critically look at all possible solutions. Because of these skills, I believe industrial hygienists can be successful in a lot of different field. I have seen IH’s become HR Managers, Lab Managers, and of course HSE Managers. The future of IH is taking on more complex issues such as determining true body burden from exposure and in understanding genetic susceptibility to disease from these exposures.

Editor: Thank you Illa! You are inspiring. You may contact Illa directly at OHSU, or at: illagjones {at}gmail.c0m

If you really have an indoor air quality and mold/fungus issue, it usually stems from moisture. I’ve talked about it before, here. The simplest answer is to find the water. Control the moisture and you inevitable will control the future indoor air quality concerns. Once you have found (and controlled) the water, then it is time to repair the damage and lingering water (which can’t evaporate).

The issue is: where does moisture come from? Well, it ‘can’ come from almost any direction:

EPA moisture control

  • from above (rain, roof vents, skylights)
  • from below (moisture in flooring, concrete)
  • walls (penetrations into the exterior, or windows and flashing)
  • out of thin air (relative humidity)

The EPA has written a new document titled, “Moisture Control Guidance for Building, Design, Construction and Maintenance“. As a contractor, how do you know when the clean up is too much to handle? I’ve written a bit more about it here.

The best time to clean up a moisture issue was yesterday, but the second best time to clean it up is today. Don’t let it sit, it usually doesn’t get any better.

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