Dental Lab Worker Safety

Previous PEL was 100 μg/m3 (100 micrograms of silica per cubic meter of air)
New PEL is 50 μg/m3 (50 micrograms of silica per cubic meter of air), averaged over an 8-hour day.
New requirement: Measure the amount of silica that workers are exposed to if it may be at or above an action level of 25 μg/m3 (25 micrograms of silica per cubic meter of air), averaged over an 8-hour day.

Previous PEL was 2.0 μg/m3 (2.0 micrograms of silica per cubic meter of air
New PEL is 0.2 μg/m3 (.02 micrograms of silica per cubic meter of air), averaged over an 8-hour day.
New requirement: Measure the amount of Beryllium that workers are exposed to if it may be at or above an action level of .01 μg/m3 (.01 micrograms of silica per cubic meter of air), averaged over an 8-hour day.
Establishes a Short-Term Exposure Limit (STEL) for beryllium of 2.0 μg/m3 over a 15-minute sampling period

The employer must assess exposures, develop and implement written exposure control plans, and provide workers with training specific to beryllium and silica. Employers must offer medical examinations to certain exposed workers.

A dress code should be established based on identified workplace hazards. Employers try to develop dress codes using OSHA as a reason for certain attire. In most states an employer may set whatever dress code they desire, but you should consult with a local attorney to ensure that your dress code doesn’t infringe on any employment law in your state. OSHA requires you to identify all workplace hazards and if wearing shorts or open-toed shoes presents a safety hazard, then you have the right to require long pants and closed-toed shoes. You should review OSHA’s Personal Protective Equipment Standard.

It is your responsibility to protect visitors from hazards by use of warning signs, verbal warnings, and/or PPE, such as safety eyewear. If it is a technical person, such as trainer or consultant, who will be working in the lab, even if just for a day, then you should tell them the lab’s dress code to abide by when working onsite.

OSHA 1910.37 requires that all emergency exits be marked with lighted Exit signs. They must be clearly visible and illuminated to 5ft candles and be a distinctive color. The word EXIT must be at least 6” high and the width of the letters no less than ¾” wide. They can be battery powered, self-luminescent or electroluminescent.

It is mandatory that the employer offer the Hepatitis B vaccination to all Category I Task employees. The employer should coordinate with their company’s doctor or health dept to administer the vaccine and it should be offered at the expense of the employer and on company time (not on the employee’s own time nor at the employee’s cost). Mileage is also reimbursable to the employee if they must drive to the doctor’s location for the vaccine. If a Category I Task employee refuses the vaccine, then the employee needs to sign the Refusal of Vaccination form (they can always change their mind later). Other Category employees can be offered it, but it is not required, nor does it have to be provided/paid for by employer.

According to the BBP standard the vaccinations must be administered by a licensed health care professional. It is the employer’s responsibility to ensure that all the expenses incurred by the employee while receiving the vaccinations are paid for by the employer. It is the employer’s responsibility to ensure that the healthcare professional has a copy of the BBP standard, the details of the incident and any medical records applicable to the case.

At the current time, the CDC (Centers for Disease Control) does not recommend a booster for Hepatitis B for responders to the vaccine. The question here is whether the employee has had a titer test after he/she completed the 3-vaccine series to determine if he/she responded to the vaccine. If the employee knows he/she was a responder to the original series, then the answer is “no” the employee does not need a booster. If the employee does not know if he/she responded to the original series, then the employer should offer the complete series again. The only exception is if they are HepB positive, then the employer is exempt from offering the vaccine, but this must be documented, signed and put in the employee’s medical file. The vaccine should be administered as follows:

3 shot series – spans 6 months

Titer drawn 1-2 months after 3rd shot

If positive, covered for life. No need to draw titers.

If negative, repeat the shot series, draw titer 1-2 months after third shot.

If still negative, the employee needs to be counseled by physician regarding what he/she will do if they have an exposure and that they must receive the HepB anti-globulin within 7 days of their exposure.

Now there is a two-shot series called HEPLISAV-B.  On November 9, 2017, HEPLISAV-B(, Dynavax Technologies Corporation, Berkeley, California, USA), a single-antigen hepatitis B (HepB) vaccine with a novel immunostimulatory sequence adjuvant, was approved by the Food and Drug Administration for the prevention of hepatitis B virus (HBV) in persons aged ≥18 years. The vaccine consists of 2 doses administered 1 month apart (1). On February 21, 2018, the Advisory Committee on Immunization Practices (ACIP)* recommended HepB-CpG for use in persons aged ≥18 years.

There are several actions you can take. Besides the usual Standard Precautions, you can rinse the impression with water and use a soft brush to remove the excess blood. Also, you can gently scrub the impression with a mixture of stone and water, or you can soak the impression in an enzyme cleaner. Always confer with the manufacturer of the impression material prior to taking any steps to clean the items prior to disinfection.

The first step is to take an inventory of all items in the lab and then begin procuring SDSs for the items. SafeLink offers an SDS online access service that can help you with this task. After you have the SDS, then you should begin labeling all containers that do not contain enough information to provide warnings of the hazards. You must determine a system to use for quick reference to the hazards.  Some dental labs are still using the National Fire Protection Agency’s system (NFPA) or the Hazardous Materials Identification System (HMIS). These systems use numbers to indicate the severity of the hazard from 0-4. Another labeling system is the GHS Pictograms. OSHA requires the Pictogram to have a red border to make it more visible. The Globally Harmonized System (GHS) requires manufacturers to use Pictograms on their product labels so you should be seeing them on products that you use in your business.  They can also be found on the product’s SDS.  This is a very simple system to use. Begin labeling with secondary containers, i.e. those products that have been removed from the original container and placed in a secondary container. You may want to begin with the hazardous items such as acids, porcelain, metals, cleaning agents, investment, gypsum, etc. If a drawer contains one product, then you could label the drawer. Don’t forget to label the bins used for storing the plaster or gypsum or investment.

OSHA requires all rotary equipment to have guards or shields. Most eye injuries in dental labs seem to occur in the model department. Remember that you don’t want to create a greater hazard by installing a shield, for instance, on the model trimmer if it impairs the worker from seeing well enough to perform the task. If you decide not to install the guard, then you need to have the workers wear close fitting safety eyewear or goggles.

Lockout is the placement of an energy isolation device on a piece of equipment to render it inoperable. A lockout uses a lock to hold an energy isolation device in a safe position and prevents the energization of the machine or equipment. Tagout is when a tag is placed on a piece of equipment to indicate that the equipment being controlled may not be operated until the tagout device is removed.

We did some air monitoring and we were found to be in the acceptable range…

Therefore, we setup a voluntary system for wearing the dust mask and/or respirator. If the associate wishes to wear the mask, do we have to have a medical evaluation and fit test performed before they can wear it?

It will depend on the type of respirator that you’re providing.  If it is the N95, then you don’t have to do the fit testing and medical questionnaire when it’s voluntary. You do need to give a copy of Appendix D to each of your employees who work with hazardous chemicals but use of the respirator is optional.

You just need to have the items to treat whatever type of injury you can treat such as a minor cut or burn or to stop a bleed prior to getting the employee to an emergency facility to treat them. Remember that it increases your liability when you provide any oral medications unless you have a nurse or doctor on staff to dispense them.

We recommend a stand-alone model and one that is a single action. You would need to find a location central to everyone and a place where it can be plumbed to water or purchase one of the portable eyewash stations that is self-contained. The eyewash must deliver 15 minutes of continuous flushing, be within 10 sec walking distance (approx. 55ft) from the hazard and have an unobstructed path of movement.

ANSI does NOT approve the personal eyewashes because they cannot deliver 15 minutes of continuous flow to both eyes. They are single use only and have a limited shelf life. They are not a substitute for plumbed or portable eyewashes.

It is an OSHA requirement under the Bloodborne Pathogen Standard that no consumable products are allowed in risk areas. We have defined those areas in the dental lab as Receiving, Denture Repair, Die Trim when clinically poured models are trimmed, and shade taking.

It is also a requirement under the Hazard Communication Standard that the employer provide a Safety Data Sheet to employees for hazardous chemicals used in the workplace. If the SDS indicates that ingestion is a route of entry, then no consumable products can be allowed in the areas where the chemical is used. Remember that eye drops, lip balm, etc. are consumable items, too.

We have found the best practice to be not to allow any consumable products in risk areas and production areas unless the employer can determine that there are no hazardous chemicals used in an area. To make it consistent throughout the work areas, we recommend eating, drinking, or use of consumable products be limited to the break room. Depending on the tasks performed in the administrative area, consumable products may be allowed in that area.

OSHA relies on other agencies to approve personal protective equipment to protect the worker from recognized hazards. They look to other agencies like ANSI and NIOSH to test personal protective equipment and equipment to ensure that it provides the protection that is intended. We are not aware of any testing that approves the use of a certain type of container in areas where hazardous chemicals are used.

Some states require a safety committee. If you’re in the states of CA, MN, WA or NC you should check the state plan to determine if you need a formal safety committee. We always recommend a safety committee to provide a way for employees to have their safety concerns addressed.

Training Records: OSHA requires that you retain bloodborne pathogen training records for employees for three years. Check Federal and State Employment laws for Retention of other Employee records.

Medical Records: OSHA requires that you retain Medical Records for length of employment plus 30 years.

OSHA has recommended that employers prepare and implement an Infectious Disease Preparedness and Response Plan.  This Plan is intended to prepare businesses for the current pandemic and help businesses deal with a future pandemic should it occur.  This Plan would contain the employer’s plans and policies relating to preventing exposures to its employees as well as the public and the employer’s stay-at-home when sick policy, employee screening procedures, visitor screening procedures, and return-to-work policy.  SafeLink Consulting has developed a COVID-19 Safety Management Program that assists in developing this Plan and its policies.

OSHA’s Respiratory Protection standard 29 CFR 1910.134 outlines the requirements which includes having a written program, completion of medical questionnaires by employees who will be required to wear a respirator, and fit testing of the respirator.

Fit testing is required prior to initial use of the respirator and annually for most respirators.  However, during this COVID-19 pandemic, OSHA still requires the initial fit testing but is not requiring the annual fit testing.  When fit test kits become easier to purchase, it is presumed that OSHA will retract this current exemption for annual fit testing.

You must document all your attempts to locate and purchase fit test kits.  That means to write down the date, company, and status of your order.  There are commercial companies that will do the fit testing for you so check the Internet for a vendor near you as this could be a good solution.

The purpose of this medical questionnaire is to determine if the employee is medically able to wear a respirator so it should be done prior to the employee being required to wear the respirator.  The form is on OSHA’s website or you can contract with a commercial vendor to have the medical questionnaire completed by each employee online.  After the form is completed, then a licensed healthcare provider must review the information and respond back to the employer if the employee can wear a respirator.

There’s a risk of exposure through co-workers who are not following safe protocols outside of work.  This would include risky behaviors such as not wearing facemasks, not observing social distancing, and not avoiding large gatherings.   The tasks in the lab that can present risk are pick-up and delivery personnel who are handling cardboard boxes, receiving personnel who are handling cardboard boxes during unpacking activities, technicians who provide shade verification services in the lab, and technicians who provide chairside services at the dental practice.  All these activities need to be assessed and appropriate safety practices be established for the protection of these employees.  The use of engineering and administrative controls should be considered first, but when they don’t control the risk then the use of personal protective equipment.

It would be appropriate for you to provide your dental clients who will be referring patients of your requirements.  The main requirement would be that you will not provide the services to any patients who are suspected or confirmed with COVID-19.  Most dental practices are screening patients upon arrival at their office, however, you shouldn’t totally rely on that screening.  It may or may not be the same day that the patient comes to your lab for the service.  You should also screen the patient just as you should screen your employees prior to providing the services.

It would be appropriate for you to provide your dental clients who will be referring patients of your requirements.  The main requirement would be that you will not provide the services to any patients who are suspected or confirmed with COVID-19.  Most dental practices are screening patients upon arrival at their office, however, you shouldn’t totally rely on that screening.  It may or may not be the same day that the patient comes to your lab for the service.  You should also screen the patient just as you should screen your employees prior to providing the services.