Industrial Hygiene in Construction

The latest push from NIOSH is ridiculous, in a bad way. It’s titled, “Recognizing N95 Day” on September 5. I’ve written about these types of respirators before.

Let’s start with:

• NIOSH estimates 20 million workers exposed to airborne health risks
• N95 (s) are the most commonly used respirator
• NIOSH certifies all respirators. And, OSHA requires all respirators to be certified by NIOSH
• All certified respirators must have an “assigned protection factor”, which is a level of protection they are able to achieve
• N95 respirators are certified to provide a protection factor of “up to” 5 times the exposure limit

For the record, I am not disputing how NIOSH certifies respirators, or if these respirators can achieve a protection factor of 5 (5x the exposure limit). I will also add that in the healthcare setting (hospitals) these might have a useful role.

Here’s the problem:

• If you need a respirator, you would NOT choose a N95. They are terrible fitting.
  • To put it another way: if you had to work in an environment which had a dangerous airborne hazard, would you CHOOSE this respirator?
  • Or another way: “There is a chance this N95 respirator might protect you, wear this just in case”. (?)
• If you have fit tested these types, you know they are hard to fit, and at best, mediocre in their protection. At times it is hard to fit test a tight fitting 1/2 face respirator on someone who is clean shaven.
• N95 respirators are handed out (like candy) at construction sites for any task which “may be hazardous”.
• Let’s be honest:
  • these are “comfort” masks. AKA:  peace of mind, not for protection.
  • these are cheap. That is why most employers buy them.
• And, let’s mention:
  • exposure levels can vary (have you measured the worst case scenario?)
  • change out schedule? Do your workers wear the same respirators every day? Do they change them when they start getting hard to breathe?
  • facial hair (no one who is on a jobsite has this, right?)
  • there are knock-off N95 respirators which actually aren’t certified (they’re fake)

In this instance I wish NIOSH would spend money on training people to use the correct type of respirator. Or, how to adequately measure the hazards found at various sites.

As a quick review. If you need to wear a respirator, here are the proper steps.

I was visiting a friend and in their neighborhood all of the curbs were cut for driveways (they were not poured for the cutouts). 

This might have saved some time for the carpenters forming & pouring the concrete. But it created additional work for the concrete cutters and the finishing of the driveways.

This lack of pre-planning created:

• additional time to cut the curb,
• dust (and silica, for sure),
• the use of additional water (hopefully) to control the dust,
• respirators (& cartridge filters),
• exposure to noise, dust, silica

I don’t know the circumstances why this occurred, but I wonder if the person planning the development thought of the exposures to other human beings?

ps. Sorry for my blogging absence. Have been on vacation! (for some of it)

There are only a few instances when you are not required to perform fit testing. The main reason not to perform fit testing is if the employees are wearing a respirator voluntary. (meaning: it’s not required)

So, how do you know if it’s required? It’s required when:

• You have overexposures to a substance (it’s required by OSHA to wear a respirator- so make sure you know, perform air monitoring), or
• If everyone is wearing a respirator during this task (it’s probably also required, just not formally- ie. spray finishing, or my favorite sanding drywall dust) or,
• If your company policy requires them to be worn (management says: it’s required to wearing a respirator during this task).

So, if you choose voluntary to wear a respirator and there is NOT a policy, or law, that says you HAVE to wear one then, you don’t need fit testing. (but you do need a few other things, Appendix D, etc.)

There is only one other exception:

• loose fitting hooded /helmet atmosphere supply respirators (when used in areas not immediately dangerous to life and health (IDLH))

Some employers choose to use these types of respirators because:

• the employee wears a beard
• it is convenient to use
• offers eye/face/neck protection
• it offers a greater protection factor
• it’s easier to don/doff (take on/off)

These guidelines for fit testing are different than medial testing before wearing a respirator, as spoken about here.

There is a lot of confusion about N95 paper dust masks. And, it is confusing. The reason is because NIOSH has rated this type of equipment as a respirator. Prior to this, it was called a “comfort mask”. This name sounded better than calling it, “a worthless false sense of protection”. It is now called a, “dust mask”, or a “filtering face-piece”.

Here is what is required by OSHA if you wear this type of respirator (N95, or similar):

• Employees must read and sign Appendix D (of the OSHA respirator standard)
• Employees must clean, inspect, and store their dust mask

That’s it.

UNLESS you are wearing this because:

• Your employer requires it
• You have overexposures
• or, nobody “wouldn’t wear it”. (meaning: it’s an industry practice, and when when we do this XXX task, everyone wears this type of respirator– this is the same as your employer requiring it)

If  any of the above statements are true, then you have more to do. Here are links for more information:

Voluntary Use of respirators

Getting ready to wear a respirator

Professionally I do not recommend these type of respirators. Email me if you’d like to know why.

Before you can wear a respirator here’s what has to happen:

If you’re an employer and your employees wear a respirator, they are required to have a medical approval (Appendix C of OSHA respiratory standard). more details here.

The employee fills out the confidential questionnaire and then submits it to the medical provider of the employer’s choice. 95% (I made that # up) of the time, based upon the questionnaire ONLY, they give an approval to wear a respirator.

Occasionally, some employees are requested to come into the medical office to have a spirometry test performed, which tests for lung function. (a video of how it is done, cool accent included) This tests provides more information for the physician/nurse to determine if wearing a respirator will be too difficult for an employee to wear.

The cost for either test is usually pretty close to the same price… spirometry test, or not.

Here’s my suggestion:  Have every employee perform a spirometry test before wearing a respirator. This helps to guarantee they are capable of wearing a respirator. Maybe they forgot to list a risk factor, maybe they have a hidden serious lung problem, or, maybe they lied on the questionnaire so they can wear a respirator and keep their job.?

It is also beneficial for pre-employment screening, claims defense, and for a baseline in health. The specific results are usually NOT view-able by the employer, but they can be subpoenaed.

If you operate a ready-mix plant and have concrete trucks, you are aware of this process. Once a year (hopefully, only once) a person must climb into the drum of the ready-mix truck and chip off excess concrete. What happen during regular use, is that some concrete hardens, which usually sets-up over and around the blades. Access into the drum is by either the 3×4 hole in the side, or down the chute.

Yes, it is a confined space (def’n: 1. large enough to enter, 2. not designed for occupancy, and 3. limited entry/egress).

Here are a list of the possible hazards:

• silica dust (from chipping concrete)
• noise exposure
• hazardous atmosphere (curing concrete uses up oxygen, which we DO need BTW)
• slipping hazard (drum is round inside)
• heat stress (if you’re trying to do this activity in the summer)
• eye hazard (chipping)
• electrical hazard (if you’re using water & have an electric hammer)
• lock out / tag out (if the truck drives away, or if the barrel starts turning)

There are many resources available (see below). Some things to keep in mind; ventilation (fans, etc) to control the airborne silica dust are usually not effective (too much dust versus exhaust). Water controls are best, but you must limit the amount of water and the direction of the sprayer. I suggest looking at what others have done.

Keep in mind, if you perform this activity you will need (as a company):

• respiratory program (medical, fit test, written plan)
• confined space program (multi gas meter, written program, attendant?)
• lock out /tag out policy or procedures
• training (for each of the above, and for this specific activity)

At this point I know what my contractor-friends are thinking…I will subcontract this out!   ha. If you do, please make sure your sub is doing it right.

Resources:

Georgia Tech – good presentation & guidance

Georgia Tech/OSHA – Safe Work Practices (in Spanish too!)

Teamsters H&S hazards & controls

Illinois DCEO – Consultation on ready mix cleaning

There are two types of fit testing, 1. quantitative and, 2. qualitative. For quantitative fit testing you’ll need a machine (ex. Portacount),  a respirator that will protect more than 50x the limits (>full face).  I will not cover this type of fit testing in this post, but it is very similar.

For qualitative fit testing you will need:

A medical clearance (not needed if you are wearing a paper dust mask) for each employee wearing a respirator.

Respirator w/P-100 filters (1/2 face respirator or more protective), aka HEPA filters, purple in color.

fit test kit -your choices are: saccharine, irritant smoke, Bitrex, or isoamyl acetate-bananas. Buy it online, or at your local safety supplier. Look at their instructions.

My preference is to use irritant smoke. The reasons are;

1.  if they cough, it means they smelled it.
2. it doesn’t require a containment to be built to perform the fit testing.

The employee must be clean shaven around where the mask touches the face.  I allow “short” goaties where the facial hair does not touch the mask. The fit test procedures are easy to follow and found inside the kit. There are 8-steps, do each one for about 1 minute each.

As you fill out each individual’s form, make sure you include:

• if the employee is clean shaven
• what type of respirator is being worn (size, brand, model)
• what type of filters are being worn
• what type of fit test kit you used

While you have the employee captive, you might as well give them some training. Here are some questions and/or points to note.

• did you train them on positive & negative fit checks?
• why are they wearing a respirator?
• what are the limitations of their respirator?
• how will they store the respirator?
• how will they sanitize it?
• will they share their respirator?

Finally, sign and date the form. It expires one year from this date. Simple? yes.  Easy to forget something? yes.

There is much confusion over the requirements and best practices of employees using respirators voluntarily.

Let me first clarify. You must do air monitoring (or have other verifiable information) that employees are not REQUIRED to wear respirators (if they are overexposed to something, you must protect them). Also, they cannot voluntarily wear a respirators if there is a known hazard above the exposure limit (the employee cannot opt-out of wearing a respirator and be overexposed).

Some points about voluntary use:

• Assuming the above statement (s) is true, firstly, you do not have to allow them to wear respirators. I am sure this is arguable from a human resources/PR/legal stance. However, if you have documented no overexposure and have not provided a respirator, they should not need to wear one.
• Next, the employees need to be educated and you need to prove it. Having them sign Appendix D of the OSHA respiratory rule is a minimum. Training them would be better.
• What respirator are they wearing? A paper dust mask (N95, P100, or similar) is a respirator. If they are wearing anything other than this type of mask they need a medical evaluation (Appendix C of respiratory standard).
• If they are wearing a 1/2 face tight fitting negative pressure respirators (or more protective ones) the company needs to have a written respiratory program.
• Fit testing is not required to be performed
• Maintenance, inspection, storage, and training should always be done. Can you verify that the employee does this?

I personally do not recommend the paper dust masks (N95, or similar) for this simple reason. Why would you wear this type of respirator if you could have a 1/2 face, tight fitting one with the correct cartridge? The cost difference is negligible, the protection is better, and you can be assured of a better fit. If you’re going to do it, do it right.

OSHA states that:

• Medical exam – must be completed prior to wearing a respirator. The individual must be examined again if there are significant changes to their medical/respiratory system.
• Fit Testing– this must be performed yearly (either qualitative or quantitative fit test, depending on the respirator) and be performed for each type of respirator worn (not for each filter used)
• Fit Checks- these are performed every time an individual puts on a respirator. Cover the inlets and breathe in (mask should collapse). Cover the exhale valve and breathe out (mask should expand)

Individual cards for employees are not required. Sometimes, when filing the medical exam, the physician/medical reviewer, will not require the individual to come into the office. As a best practice, I would have every employee fill out the paperwork and see someone in the medical office. Employees have every reason to want to pass this “exam” and they may leave out things on the written exam that are easily discovered (or may be obvious) when someone sees them in person.