Only the enforcement of the new silica rule has been delayed until September 23, 2107.  The Federal OSHA silica rule is still being implemented and will take effect on June 23, 2017.

OSHA says in their memorandum they are delaying the enforcement because they hope to develop additional guidance materials and train their compliance officers.

I suspect that many individual state plan OSHA (like Cal-OSHA, etc) may also delay like Federal OSHA, whether or not they announce it.

The new silica rule for construction is a lot of work, retooling, and training. If you haven’t started, there’s no time to lose. I would suggest you start by:

  • Examine the tasks you perform which may have dust exposure (grinding, concrete cutting, milling, etc.)
  • Refer to the Federal OSHA Small Entity Guide and see if you are properly tooled (have the correct equipment to control exposure)
  • If the tasks aren’t listed in Table I – then you have more work to do (look at alternative control methods)
  • Train your employees. Both in general awareness & for the competent person. Consider making your own company training video (like this one). Don’t worry, it doesn’t have to be awesome Hollywood cinematography…but having a training which is specific to your company, tools, and activities is best.

There is a lot more to the rule, but the above steps are the best place to start.

At this point, the OSHA silica rules are forthcoming, what should you be doing to prepare?

  • Read the OSHA Small Entity Guide. Initially it is daunting – 103 pages, but much of it is specific to tasks from Table 1 and the full rules are within it, as well. Plus, they have pictures!
  • Identify tasks which could have silica exposures silica-grinding
  • Train employees, identify your “competent person(s)” – my suggestion is: Superintendents/Project Managers
    • Warn those on your projects: NO VISIBLE DUST on any tasks (cutting, finishing, dry sweeping, etc.)
  • Document activities with airborne silica exposures below 25 ug/m3
  • Identify possible solutions for overexposures
    • Verify airborne levels with personal air sampling
  • Start a process to log the number of days with (any) exposure – >30 is inclusion into medical
  • Find a medical provider that can have medical screen performed & with a B reader

*Thanks Andrew for the photos*


Exciting news! In just a few months we will be releasing free training materials!

In summary: I applied (and obtained) a grant through OSHA to produce training materials for the four major health hazards in construction. We are titling it, “Focus 4 Health Hazards for Construction”.  (similar to the Focus 4 Susan Harwood training materials available at OSHA)

Indented audience is for younger construction workers in hazard recognition of, 1. silica, 2. noise, 3. asbestos and 4. lead (pb) in construction. A short video (1-4 minutes) for each subject gives an introduction to the hazard. And, to follow up a training power point presentation (and short summary) will also be available to further instruct people in how to control and protect themselves.

On a personal level…it has been exhausting, and I’ve learned a lot!  From obtaining the grant, to hiring a videographer, filming, securing filming sites, and quarterly reports…. exhausting.  But, I’m confident you (and others) will enjoy it. Subscribe (via email) to keep updated. You can also follow me on instagram: “adventuresInIH”. (link coming)

grant filming

You’ve probably heard the Federal silica proposed-rule has moved in it’s next step towards being a promulgated-rule.

And, you’ve hopefully looked at my prior post about the positives and negatives of the rule. I am usually not in favor of more rules, but as a safety person, my overall opinion is the new rule would be good.

However, there is some opposition (EHS Today Summary Article) from a few industry groups and associations, including ARTBANAM, and the ACC in an article to plastic manufacturers. And just recently a lawsuit was filed to stop the rule. They have some good arguments, of which, I think the best are: THERE ARE ALREADY OVEREXPOSURES at the current PEL, and silica related deaths have been in decline for decades.

The ACGIH and NIOSH have been recommending lower airborne limits for years. If you are a construction firm, hopefully you already have (engineering & administrative) controls and respiratory protection in place. If not, the best time to start was yesterday, and the next best time is tomorrow.

cut off saw


OSHA has recently announced the final time frame for the proposed silica rule. February 1, 2015 is their anticipated rule promulgation. However, we will see if anyone protests this new information, and if the date for final rule “sticks”.

AIHA broke the news (at least to me) and you can see their summary here. If this is the first you’ve heard about this new rule, then it’s time to do some research, and I might recommend starting here. There are quite a few new requirements, including a lower permissible exposure limit (PEL).

dust exposure

These pictures will come as no surprise. But, silica dust exposures (and nuisance dust) is an ongoing issue. Bottom line: if you have dust, you need to add some controls.

Platform of rock crusher (photo courtesy BP)
silica 5

Crusher operations (photo courtesy BP)silica 6

Grinding asphalt with a Bobcat (photo courtesy AH) silica 7

NIOSH (and with the help from some other groups) released a document this last week titled, “Best Practice Engineering Control Guidelines to Control Worker Exposure to Respirable Crystalline Silica during Asphalt Pavement Milling”cold milling machine

The issue: These machines are used to remove asphalt roads. They have a drum with teeth on them that essentially chew up the road and asphalt. A lot of respirable silica is generated (based upon the amount of silica in the rocks). The drums get really hot so water is used to cool it.  However, it does not control the respirable silica dust.  I’ve written (or, maybe complained) about the issue here, in 2010. And, I was informed, some good people were working on it.

The solution: The quick summary is: add more water and ventilation. Not rocket science, right? However, after reading this document, it might be. There’s a lot of information and specifics on what worked, and what didn’t. It was almost too much detail, but I suppose if you have a $200k+ machine, it is worth the time to figure it out. Below are some details:

  • Case studies – adding water and increasing the pressure flow decreased airborne dust
  • Tracer gas studies for ventilation effectiveness
  • Checklists and flow rate controls
  • Diagrams for where to direct water

Another benefit was the documentation of other’s work. There are numerous references  (5 pages!) to scientific articles. I did not notice any cost to implement the recommended changes, and I am curious to know what adding the ventilation system might run. Overall the document is good.

Finally, if you hold-on and continue reading to Appendix C, let me know what that all-means.  🙂



I was asked to summarize my thoughts on the OSHA proposed silica rule (which is currently pending). I’ve done it before, but since it was for the ASSE’s Industrial Hygiene Practice Specialty, it seemed fitting to post it on this site as well.

Wondering what is happening with the OSHA crystalline silica rule? In aviation terms it’s called a holding pattern. This airplane may-or may not-land. And, it is anyone’s guess.

If you haven’t heard, Federal OSHA is proposing to reduce the airborne silica permissible exposure limit (PEL) to 50 µg/m³. It is difficult to say how much lower this new rule will be, since the current standard relies on a calculated formula to obtain the exposure limit. However, for rounding purposes, let’s just say it’s a 50% reduction in the PEL. This limit is the same at the NIOSH Recommended Limit but still above the ACGIH (2006) Threshold Limit Value of 25 µg/m³.

Over the last year my views on this rule haven’t changed much: It’s a mixed-bag. There are still overexposures to silica. However, will the new rule change behavior?

To show some of the contrast, let me explain. Overexposures to airborne crystalline silica are still occurring. However, silica deaths have continued to decrease over the recent past (without the new rule). But, will the small employers comply? Or just wait to be cited? There is rarely a perfect solution for all situations. I’d like to provide a perspective balance to both sides of the rule.

The obvious benefit to lowering the silica exposure limit will be to protect overexposures to silica. I believe the rule will accomplish this in a number of ways. Any new rule will generate increased awareness for the subject of silica. The new rule will drive OSHA compliance by both lowering the PEL and by compliance with their additional controls. This will drive changes and modification to industries. Innovation will be spurned for controls and the need to comply.  In turn, this will create more discussions on the topic, the solutions, and overall awareness.

The new rule will get closer to the ACGIH TLV and update the health standards. The original rule was from the 1970s. And, OSHA is on the prowl for ways to update their current PELs.

Health and safety consultants will have an occasion for additional revenue in training, air monitoring, recommending controls, and other opportunities.

The new rule allows for alternatives to sampling. Rather than air sampling, you can choose to “over protect” and assure employees are controlling silica exposures.  This is a great solution for short duration tasks where exposure monitoring is prohibitive (see Table 1 from OSHA’s Fact Sheet). They emphasize control measures for silica.

There are very few new products and control measures for mitigating silica exposure in industry. Technology has somewhat sidestepped innovating products for dust capture and control for concrete work. Hopefully new products will be created to control silica. If nothing else, maybe we will see frequent job safety analysis (JSA, JHA) as a common practice to control exposures.


However, there are notable weaknesses to the proposed rule. The obvious downside is employers are expected to spend money. This will be an additional cost to doing business. Money will be spent on citations, controls for silica, labor during the activities, and for consultants to verify exposures are below the PEL.

This new rule will also allow OSHA to issue citations easier.  There are many items in the new rule which are beyond merely lowering the exposure limit. I imagine compliance officers will cite for failure to implement controls, or other technical aspects, rather than measuring the airborne dust and finding overexposure. Look for more drive-by citations.

And, there will be more confusion. Remember explaining to people how to calculate the current PEL? Well, in the short term, it won’t get easier. Although the PEL will be a fixed amount, there will be other things to explain. And, remember all the OSHA rules for leaded paint? The new rule is similar in how it allows you to provide adequate PPE and controls for “interim” work without measuring airborne levels.  Imagine you are a smaller contractor employer. This will be confusing and a lot of background work in order to use a jackhammer for one small project.

And, analytically, the airborne levels attempting to be achieved are so low, they are at the laboratory detection limits. With laboratory I currently use, to reach the detectable minimum PEL you will need to sample for at least 80 minutes (200 Liters). There is some newer sampling equipment which makes these levels easier to achieve. But, guess what? That will cost more money.  In addition, contained in the rule are mention of specific medical evaluations and facilities for those with continued overexposures. There are not enough medical facilities to support the number of people who need them.


Overall, I believe the new silica rules will help reduce overexposures to silica. The increase in awareness across the US will bring more attention to the danger. Employers who are doing absolutely nothing to control silica will get caught, punished, and hopefully change their ways. For employers already in compliance, there will be a small, but manageable, learning curve. I also see many contractors using interim controls (Table 1) as a guide to easily protect employees on short tasks with high silica exposures.

To stay ahead of the curve, the AIHA has released (2013) a white paper for guidelines on skills & competencies in silica specific to construction. It is a great outline for training your employees. Another great resource for awareness and silica control measures is As a reminder, pre-task planning is still one of the best methods for health and safety.

 Here’s my sampling outfit.

my silica bag


Here’s my top 5 gifts for Christmas in the (my) occupational hygiene world of construction:

  1. A new carbon monoxide monitor.
    • Not just a “normal” $40 model. A Nest Protect Fire & Carbon Monoxide monitor, which is in the $100 range. This thing is sweet. Talks to you, sends you a text message. Here’s a review from Cool Tools. Or, just buy it here.
  2. High flow air pump, Gast model.
    • I have some other flow rate pumps up to 5 liters per minute (LPM), but this one is great for flow rates 10-up to 28 LPM (depending on the model). Good for high volume area type samples and vacuum wipe sampling. You must have 110 power available, but once calibrated, it’s a done-deal. They can be bought for under $250. Grab a rotometer too, if you don’t have one.gast pump
  3. Wireless response system to use during training.
    • Attendees have a wireless response keypad and the trainer can ask a multiple choice question. It allows the audience to reply. The results then show up on the screen. Great for anonymous responses, or a general overview from your audience. There are several vendors, here’s an example, and the leader in the industry is Turning Point. I think these are in the $500-$1,000 range.
  4. A bulk asbestos example kit.
    • A bunch of “typical” building materials which are asbestos containing. In sealed glass jars, of course. I don’t know where you’d buy this sort of thing. I wish I would have kept all of my samples over the years.
  5. A dedicated short term silica sampling kit.
    • SKC has a new sampler which can sample at a higher flow rate  of 8 LPM, compared with the usual 2.5, or 1.8 LPM. (which, if you think through the math; allows you to achieve a detection limit with a lower sample volume, and a shorter time duration) Unfortunately, you must purchase a new SKC Leland pump/charger, PPI sampler, calibration junk. Total cost is probably in the $2,000 range.


I titled this post, “hazards of drywall”, but it encompassing most of the common hazards of plaster, mud, gypsum, wall-hangers, tapers, and acoustic employees.

  1. Corrosive drywall.

    I have not dealt with this subject on a personal level. However, AIHA has a new guidance document titled, “Assessment and Remediation of Corrosive Drywall: An AIHA Guidance Document“, which is a clarification of an earlier white paper document from 2000, titled, “Corrosive Drywall“. The danger is from a specific type of drywall which was imported from China. After installation it is known to emit sulfide vapors, which corrode copper (electrical wires), and can give off a sulfur smell (HT to JeffH in Ohio).

  2. Asbestos in mud/plaster.

    Be aware, some older buildings (pre 1980s) may have asbestos in the mud compound or plaster (not as common). This will be a concern if you are performing demo on these walls. Info here.

  3. Silica (dust) in joint (mud) compound.

    Some types of silica I have found to have silica. This can be an issue when sanding. AND, if you install drywall like me…you do a lot of sanding. More information from an earlier post can be found here. NIOSH has some suggestions too.

  4. Leaded sheetrock. If you are installing (or demo) leaded sheetrock, you NEED to protect yourself. Airborne levels of lead can approach the exposure limits, even during installation. More info here.
  5. Lead in paint. If you’re tying into existing plaster/drywall and there’s paint, you need to know if there’s lead in it. Sanding on the paint is a good way to be exposed. More info here.
  6. Ergonomics. Hanging the wallboard takes a toll on your body after 20 years (or less). Not to mention sanding. Washington OSHA (L&I) has a good demo.
  7. Noise. Cutting steel studs, powder actuated tools (there’s lead exposure too, you know).
  8. Skin hazards. Cutting, but also dermatitis from prolonged exposure to dust.
  9. Eye hazards. Dust, carpentry, etc. Working overhead is an easy way to get falling items in your eyes.
  10. Falls. Last on my list, but certainly not the least. Scaffolding, working from ladders, and using stilts, to name a few.

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