Hazardous Communication Standard and Hazardous Waste Regulations in Dentistry

Eve Cuny, MS

May 2020 RN - Expires Saturday, December 31st, 2022

American Dental Assistants Association


Chemical agents are used every day in health care settings throughout the United States. Dental offices rely on chemicals to disinfect contaminated surfaces, etch teeth before application of resin restorations, disinfect canals during root canal treatment, and for countless other purposes. These benefits do not come without some risks. Inappropriate handling, use, and disposal of chemicals have been responsible for injuries, illnesses, and environmental pollution. In response to concerns about exposure to hazardous chemicals in the workplace, the U.S. Occupational Safety and Health Administration (OSHA) issued the Hazard Communication Standard in 1983. The latest update was published in 2012. This broad regulation applies to all workplaces that have at least one employee. Because the same rule applies to industrial and professional settings, a thorough review of the regulation as it relates to the practice of dentistry is necessary. At first glance, the regulation would seem to apply to those workplaces that have large amounts of hazardous chemicals in use on a regular basis. However, the Hazard Communication Standard applies to all workplaces that have at least one employee that is exposed to potentially hazardous chemicals on the job. Additional rules for hazardous waste complete the cycle of responsibility for hazardous materials in the workplace.

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About 43 million American workers are exposed to chemicals in the workplace. Chemical exposures may cause or contribute to many serious health conditions such as organ damage, respiratory failure, illness, cancer, burns, sterility, and dermatitis. There are more than 600,000 existing chemical products, with hundreds more entering the marketplace every year. Often employers and employees are unaware of the potential adverse effects of these chemicals. Of occupational concern is proper usage, storage, handling, and first aid procedures associated with chemicals. In response to these issues, the Occupational Safety and Health Administration (OSHA), a division of the U.S. Department of Labor, issued the Hazard Communication Standard in 1983. This standard was revised in 1987 and again in 1988. In 2012, OSHA adopted major changes to align with the United Nations' Globally Harmonized System of Classification and Labeling of Chemicals. The standard addresses specific issues related to chemical hazards in the workplace and gives guidelines for developing a Hazard Communication Program. However, OSHA does not dictate how the provisions of the regulation must be met. It is the responsibility of each employer to assess the hazards present in the workplace and determine the appropriate level of training and precautionary measures.

Additional regulations that relate to hazardous chemicals in the workplace exist. Most notable are the requirements for hazardous waste storage and disposal. In this article, the requirements of the Hazard Communications Standard and hazardous waste regulations including means of compliance as they relate to the practice of dentistry will be discussed.


A matrix of regulations applies to hazardous chemicals and this may create confusion for those trying to meet regulatory requirements. Briefly stated these regulations fall into three general areas. Hazard Communication is an OSHA regulation, and as such, has provisions that are intended solely to protect the health of the working people of the United States. This regulation will be outlined in detail later in this article. Hazardous Materials Registration is required in many locations to provide emergency response personnel with access to information about chemicals that may pose a special hazard in the event of fire or other emergency. It is simply a list of all chemicals in the workplace that is submitted to the local health department upon their request. The registration may also require the employer develop a written hazard response plan and address additional issues such as proper storage and labeling of chemicals in the workplace. The third area of concern with chemicals is the storage, transportation, and disposal of chemical waste products that may pose a threat to the environment or to human health.


The Environmental Protection Agency (EPA) regulates chemicals as they relate to the environment. A hazardous waste is a waste, or combination of wastes which because of its quantity, concentration, or physical or chemical properties may:

1. Cause or significantly contribute to an increase in mortality or an increase in serious irreversible illness, or
2. Pose a substantial present or potential hazard to human health or the environment when improperly treated, stored, transported, or disposed.

A discharge to the water, land or air chemicals that may be hazardous is under the jurisdiction of the EPA. The EPA classifies hazardous chemicals into four major categories. The categories include chemicals that are flammable, corrosive, toxic, or reactive. Specific guidelines for classification of hazardous waste exist and may vary from state to state. In general, the classification definitions are as follows:


• It is not aqueous and when mixed with an equivalent weight of water, produces a solution having a pH less than or equal to 2, or greater than or equal to 12.5.
• It is not a liquid and when mixed with an equivalent weight of water produces a liquid that corrodes steel at a rate greater than .250 inch per year at a temperature of 130F.


• Normally unstable and readily undergoes violent change without detonating.
• Reacts violently with water.
• Forms potentially explosive mixtures with water.

When mixed with water, it generates toxic gases, vapors, or fumes of a quantity sufficient to present a danger to human health or the environment.
• Contains enough cyanide or sulfide to react with a pH between 2 and 12.5 and generate toxic gases, vapors, or fumes in a quantity sufficient to present a danger to human health or the environment.
• Is capable of detonation or explosive reaction if it is subjected to a strong initiating source or heated under confinement.
• It is readily capable of detonation or explosive decomposition or reaction at standard temperature or pressure.
• Is a forbidden explosive per 49 CFR Sec. 173.51, Class A explosive per 49 CFR Sec. 173.53 or Class B explosive per 40 CFR Sec. 173.88.


• A liquid other than an aqueous solution containing less than 24% alcohol and has a flash point less than 140 F.
• A liquid capable under standard temperature and pressure of causing a fire through friction, absorption of moisture or spontaneous chemical charges and when ignited burns so vigorously and persistently that it creates a hazard.
• Ignitable compressed gas.
• Oxidizer as defined in 49 CFR 173.151.


• An acute injurious effect exhibited immediately or shortly after exposure.
• A chronic injurious effect exhibited later.

It is often difficult, if not impossible, for the dental team to determine what may be a hazardous waste. Fortunately, most counties have readily available resources to assist in making these determinations. The local Department of Toxic Substances Control or the Department of Public Health are commonly the local agencies responsible for administration of hazardous waste and hazardous materials regulations. Often, the companies that offer hazardous waste disposal services are able to provide dental offices with the necessary information to comply with the hazardous waste regulations. These companies often offer additional services such as labeling of wastes, proper containers, training, and inspection.


Manifests are required tracking documents that must be completed for every hazardous waste. The exemption is for wastes that will be recycled such as amalgam. The manifests are provided by the hazardous waste hauler and provide the regulatory agencies with a means to calculate amounts of hazardous wastes from a single business, a specific location, or an industry. In some states, the dental office must submit a copy of the manifest to the EPA within thirty days of the date the waste was picked up. The waste hauler should not retain the copy that is to be mailed by the generator of the waste. Some companies will offer to mail in the required copy as a service to their customers. It is not a good practice to relinquish that responsibility.

Instructions for management of the manifest should appear on the back of the document. A copy of the manifest must be maintained and available for inspection for a minimum of three years. Because of "cradle to grave" laws that make every generator of hazardous waste responsible for the hazardous waste until it is destroyed, it is prudent to retain all manifests, keeping only those required for inspection accessible to the regulatory agencies. Manifests that are more than three years old should be boxed and stored with other important, but inactive, records. Hazardous waste regulations vary greatly from state to state and county to county. Some locations may require specific permits for any type of in-office treatment, such as silver recovery for recycling. Additionally, many locations provide exemptions for metal waste that can be recycled as scrap, including amalgam.

All hazardous waste must be labeled with the identity of the substance and the starting date for accumulation. Time limits for storage exist, and will vary depending on location. In general, small quantity generators such as dental offices may store hazardous waste up to one year.

Hazardous waste may not be placed with the regular trash, poured down the drain, or discharged to the environment in any manner. The local state or county toxics division of the public health department generally sets specific limits. These limits can vary greatly in different locations and may make the difference in how some products must be disposed. In some locations, the developer from x-ray processing units does not contain silver in amounts that exceed the discharge limits. In other locations, especially in counties where certain types of manufacturing take place, limits are strict enough to require all x-ray-processing chemicals be handled as a hazardous waste.

The dental team rarely has the resources to perform a hazardous waste determination. Local regulatory agencies, and in some cases, component dental societies, are a good resource for determining specific limits and requirements for a given area. Some commonly found dental products that are usually classified as regulated hazardous waste are glutaraldehyde, x-ray fixer, and scrap amalgam (unless recycled), among others (Table 1).


The Hazard Communication Standard is intended to ensure the evaluation of the hazards of all chemicals produced or imported, and the communication to employers and employees of appropriate handling and safe use of chemical products. This regulation is also called the employee "right-to-know" law. The responsibility for providing information is as follows:

• Chemical manufactures and importers:Determine the hazards of each chemical or product.
• Chemical manufactures, importers, and distributors:Communicate the hazard information and associated protective measures downstream to customers through labels and Safety Data Sheets (SDS).
• Employers:Identify and list hazardous chemicals in the workplace. Obtain Safety Data Sheets (SDS) and labels for each hazardous chemical. Develop and implement a hazard communication program including the items identified in this article.

This regulation is performance oriented, which means that the specific methods by which to comply are not dictated by the regulatory agency. Each employer must become familiar with the requirements of the Hazard Communication Standard and ensure compliance. It is permissible for the employer to delegate certain tasks to staff members, such as maintaining a current inventory and ensuring a SDS is available for each product. The employer cannot delegate responsibility for compliance and should maintain overall control of the program.


All employers must develop, implement, and maintain a written hazard communication program for the workplace. This written program must describe how the requirements for container labeling, SDS, and employee information and training will be met. The written program must contain a list of the hazardous chemicals in each work area, who is responsible for the program, how the criteria for labels, SDS and training will be met, and the means by which the employer will inform employees of hazards of non-routine tasks. If there are several dentists working in one clinic or practice, they must inform other employers of hazards and protective measures. Numerous resources are available from OSHA to assist with understanding and complying with the Hazard Communication Standard. These resources may be found at www.osha.gov/dsg/hazcom/index.html.

Self-evaluation is an important tool in ensuring compliance. The following checklist will help ensure compliance with the regulation.

1. Obtained a copy of the rule
2. Read and understood the requirements
3. Assigned responsibility for tasks
4. Prepared an inventory of chemicals
5. Ensured containers are labeled
6. Obtained SDS for each chemical
7. Prepared written program
8. Made SDS available to employees
9. Conducted training of workers
10. Established procedures to maintain current program
11. Established procedures to evaluate effectiveness

Container Labeling

All containers of hazardous chemicals must be labeled before shipment. The determination of what must be on the label is the responsibility of the manufacturer, distributor, or importer. This means that all containers entering the dental office have been properly labeled and do not require additional labels to be affixed. The information that is required includes:

• Product Identifier (may be name, code, batch, etc.)
• Signal Word ("Danger" or "Warning")
• Pictogram (Figure 1)
• Hazard Statement
• Precautionary Statement
• Name and address of the chemical manufacturer, importer, or other responsible party.

Because it is the manufacturer's responsibility to provide the appropriate label, dental office personnel do not need to add additional labels as items are received in the office. If a chemical product is to be removed from its original container and placed in another container for use by an employee, labeling of the secondary container is required. The one exception is if that product is intended for use by the employee placing it into the secondary container during that work period (i.e.: placing temporary resin material into a plastic cup for use at chairside). The containers requiring a label be applied by the dental staff would include containers such as spray bottles of disinfectant, small bottles used at chairside containing product poured from a larger container, containers of sterilant/disinfectant, x-ray processing baths and auto-processing units, ultrasonic units, containers of gauze soaked in disinfectant, etc. A simple method of determining if a product requires a warning label is to check the original container. If there is a warning label on that container, one must also appear on the secondary container.

This information may be communicated through words or symbols. There are several ways of complying with this requirement. The easiest and least expensive is to request adhesive labels from the distributor. These are generally available for products such as spray disinfectant and x-ray processing chemicals. Products for which adhesive labels are not available may be labeled with a computer-generated or a typewritten label may be made and secured to the container with waterproof tape. Commercial labels such as those employing color-coding or the National Fire Protection Association (NFPA) hazard numbering system comply with the regulation. These tend to be more expensive and require additional training of personnel to understand the hazard codes.

Hazardous Chemical Inventory

It is important to conduct a complete inventory of the dental office to identify the hazardous materials that must be included in the Hazard Communication Program. It is best to methodically inventory all areas of each room in the office. All products that contain a hazard warning on the original label should be listed on the inventory. The name of each manufacturer should also appear on the inventory with the corresponding product. Exceptions to the rule do exist and are outlined in the following section.


Safety Data Sheets (SDS) are to be provided by the manufacturer, importer, or distributor for each hazardous substance. Additionally, the manufacturer or distributor must provide updated SDS when appropriate. Employers must have a SDS for every hazardous chemical that they use, and the SDS for each product must be available to employees in the workplace. In order to determine if all needed SDS have been obtained, a list of chemicals needs to be compiled. Conducting an inventory as described above will do this. Only items that contain a hazard warning on the original label need be included on the inventory list. A sample inventory form is provided in Figure 2.

Some potentially hazardous materials are exempt from the hazard communication standard and do not need to be included in your written program. The products which are exempt and may be found in a dental office include hazardous wastes (regulated by EPA), food, food additive, drugs, cosmetics, medical devices, alcoholic beverages, and consumer products unless employee exposure is greater than exposure to an ordinary consumer. Products such as sodium hypochlorite used for root canal irrigation and disinfection are subject to the regulation. Products such as abrasive cleaners used to clean non-contaminated surfaces in the same manner they would be used in a household are not subject to the regulation. The amount and use of the consumer product will determine whether or not it must be listed on the inventory sheet and a SDS maintained.

Once the inventory has been completed, a SDS for each item listed must be collected and provided in an accessible area for the employees using the listed products. It is generally easiest to compile a binder with the SDS collected in alphabetical order, by common name. For very large clinics or dental practices, it may be necessary to provide separate binders for different areas. The key to determining if separate files are needed is to determine if the SDS for products being used by employees are easily accessible to those employees during their use of the products. If first aid information is needed due to accidental exposure to a hazardous substance, the employee should not have to spend time searching for the SDS binder. Placing SDS in a binder and placing it on a shelf does not comply with the Hazard Communication Standard. Employees must receive training in how to safety handle, store, and dispose of hazardous materials, and must understand the health hazards associated with each material. Employees must also know how to recognize an accidental release, perform proper cleanup procedures, and the first aid requirements in case of accidental exposure through contact, ingestion, or inhalation.

The SDS must be in English, reference the common name of the product, and contain information regarding the specific chemical identity. There are commercial programs, both written and computer software, available which provide numerous SDS with chemical generic names. This would not meet the requirements for the dental office of referencing the common name (i.e.: the specific brand of disinfectant used). The manufacturer or distributor must provide the SDS. If the SDS for a particular product is not provided, the employer must request it. This request should be in writing. If the requested SDS is not received with 25 working days, it is required that the employers notify the local OSHA office regarding the distributor or manufacturer's failure to comply. The manufacturer has a responsibility to prepare and supply the SDS, but it is the employer's responsibility to ensure the information is available.


When receiving a shipment of supplies, the inventory list should be checked to ensure an SDS is on file for that product. If a new brand of product is being used, or a distributor provides an updated SDS, the new SDS should be placed in the SDS file, and the old one discarded. Training on proper handling, storage, personal protection, and accidental release detection is required before a new chemical product may be used. It should be clearly stated in the written Hazard Communication Program who will be responsible for maintaining the SDS file and inventory. Additionally, all training should be well documented by outlining the content of the training session, who conducted the training, and who attended.

All SDS must contain at least the following information:

• _ Identification, including product identifier, manufacturer or distributor contact information, recommended use, restriction on use;
• Hazard(s) identification;
• Composition/information on ingredients;
• First-aid measures;
• Fire-fighting measures;
• Accidental release measures;
• Handling and storage;
• Exposure controls/personal protection;
• Physical and chemical properties;
• Stability and reactivity;
• Toxicological information;
• Ecological information;
• Disposal considerations;
• Transport information;
• Regulatory information; and,
• Other information.


Hazard communication training must be provided to employees who may be exposed to hazardous chemicals in the workplace. In addition, training of all employees of the requirements adopted in 2012 must take place by December 1, 2013. This training must be provided at the time of initial assignment, whenever a new hazard is introduced into the workplace, or if the employee is reassigned.

There are minimum requirements for employee information and training that must be met. At a minimum, the discussion topics must include:

• The existence of the hazard communication standard and the requirements of the standard;
• The components of the individual hazard communication program;
• Operations in work areas where hazardous chemicals are present;
• Where the employer will keep the written hazard evaluation procedures, written program, and SDS forms.

A formal training program is required. A summary of the training contents should be provided along with a list of employees attending the training session, the name of the person conducting the training, and the date of training. These records should be kept for a minimum of three years. OSHA has identified the minimum requirements for the content of a hazard communication training program as follows:

• How the hazard communication program is implemented in the office, how to read and interpret information on the SDS, how employees can obtain and use available hazard information;
• The hazards of chemicals in the work area;
• Protective measures to prevent exposure;
• Specific procedures to provide protection such as personal protective equipment, work practice and engineering controls; and
• How to detect the presence of a hazardous chemical (smell, appearance, etc.).


The Hazard Communication Program applies to all dental offices. It is possible to have a simple program, which can easily be updated as needed. The most important considerations are appointing a person who will be responsible for maintaining the inventory and ensuring employee training be conducted and documented. Once a program is in place, annual retraining and periodic discussion at staff meetings should keep everyone up to date on the safe handling of chemical products.


OSHA maintains a website with information related to the Hazard Communication Standard, including copies of the regulation, links to state OSHA programs, fact sheets, sample pictograms and numerous other resources to assist in compliance. The materials may be accessed at: www.osha.gov/dsg/hazcom/index.html

Hazard Communication. Final Rule. Federal Register Volume 77, Number 58 (Monday, March 26, 2012)] [Pages 17574-17896]

About the Author

Eve Cuny, MS
Eve Cuny is the Director of Environmental Health and Safety and Associate Professor at Pacific Dugoni School of Dentistry. Ms. Cuny is a consultant to the ADA Council on Scientific Affairs and the FDI Education Committee. She has served as an expert reviewer and advisor to the Centers for Disease Control and Prevention and is past chairperson of the Organization for Safety, Asepsis and Prevention (OSAP). She is the primary author of the World Health Organization's guide to infection control in oral health care and has published numerous articles and textbook chapters on safety and infection control. She has lectured widely on infection control and patient safety throughout the world.


ACGIH - (American Conference of Governmental Industrial Hygienists) - an organization of professional personnel in governmental agencies or educational institutions engaged in occupational safety and health programs; establishes recommended occupational exposure limits to chemical substances and physical agents.

Acid - any chemical that undergoes dissociation in water with the formation of hydrogen ions; have a sour taste and may cause severe skin burns; turns litmus paper red and have pH values of 0 to 6.

Acute effect - adverse effect on a human or animal that has severe symptoms developing rapidly and coming quickly to a crisis.

Acute toxicity - acute effects resulting from a single dose of, or exposure to, a substance; ordinarily used to denote effects in experimental animals.

Adenocarcinoma - a tumor with glandular (secreting) elements.

Adenosis - any disease of a gland.

Aerosol - fine aerial suspension of particles sufficiently small in size to confer some degree of stability from sediment (e.g., smoke or fog).

Alkali - chemical substance that forms soluble soaps with fatty acids; also referred to as bases; may cause severe burns to the skin; turns litmus paper blue and have pH values from 8 to 14.

Allergic reaction - abnormal physiological response to chemical or physical stimuli.

Anesthetic - a chemical that causes a total or partial loss of sensation; overexposure to can cause impaired judgement, dizziness, drowsiness, headache, unconsciousness, and even death; examples include alcohol, paint remover, and degreasers.

ANSI - (American National Standards Institute) a privately funded, voluntary membership organization that identifies industrial and public needs for national consensus standards and coordinates development of such standardize.

Aquatic toxicity - adverse effects to marine life that result from being exposed to a toxic substance.

ASTM - (American Society for Testing and Materials) the world's largest source of voluntary consensus standards for materials, products, systems, and services; a resource for sampling and testing methods, health and safety aspects of materials, safe performance guidelines, effects of physical and biological agents and chemicals.

Ceiling limit (PEL or TLV) - maximum human exposure limit for an airborne substance that is not to be exceeded even momentarily.

CAA - (Clean Air Act) enacted to regulate/reduce air pollution; The U.S. Environmental Protection Agency administers CAA.

Carcinogen - substance or agent capable of causing or producing cancer in mammals, including humans

CAS - (Chemical Abstract Service) an organization under the American Chemical Society; abstracts and indexes chemical literature from all over the world in "Chemical Abstracts"; CAS Numbers are used to identify specific chemicals or mixtures.

CFR - (Code of Federal Regulations) a collection of the regulations that have been promulgated under United States Law.

Chronic effect - adverse effect on a human or animal body, with symptoms that develop slowly over a long period or that recur frequently

Chronic toxicity - adverse (chronic) effects resulting from repeated doses of or exposure to a substance over a relatively prolonged period; used to denote effects in experimental animals.

Combustible - term used to classify certain liquids that will burn, on the basis of flash points.

Common name - means used to identify a chemical other than its chemical name (e.g., brand name or generic name).

CPSC - Consumer Product Safety Commission.

CWA - (Clean Water Act) enacted to regulate/reduce water pollution.

Cytology - scientific study of cells.

Dermal toxicity - adverse effects resulting from skin exposure to a substance; used to denote effects in experimental animals.

Dysplasia - abnormality of development.

Dyspenea - sense of difficulty in breathing; shortness of breath.

Edema - abnormal accumulation of clear watery fluid in tissues.

Endocrine glands - glands that regulate body activity by secreting hormones.

Environmental toxicity - information obtained as a result of conducting environmental testing designed to study the effects on aquatic and plant life.

Epidemiology - science concerned with the study of disease in a general population.

FDA - U.S. Food and Drug Administration.

Fibrosis - abnormal thickening of fibrous connective tissue, usually in the lungs.

Flashpoint - minimum temperature at which a liquid gives off a vapor of sufficient concentration to ignite when tested using standard methods.

Fume - solid condensation particle of extremely small diameter, commonly generated from molten metal as a metal fume.

Hematoma - blood clot under the skin.

Hepatotoxin - substance that causes injury to the liver.

Hyperplasia - increase in volume of a tissue or organ caused by the growth of new cells.

Mist - suspended liquid droplets generated by condensation from the gaseous to the liquid state, or by breaking up a liquid into a dispersed state, such as splashing, foaming or atomizing; formed when a finely divided liquid is suspended in air.

Mutagen - substance or agent capable of altering the genetic material of a living cell.

Narcosis - state of stupor, unconsciousness, or arrested activity produced by the influence of narcotics or other chemicals.

Neoplasia - condition characterized by the presence of new growths (tumors).

Nephrotoxin - substance that causes injury to the kidneys.

Neurotoxin - material that affects the nerve cells and my produce emotional or behavioral abnormalities.

NIOSH - (National Institute for Occupational Safety and Health) non-regulatory government agency.

Oxidizer - chemical other than a blasting agent or explosive that initiates or promotes combustion in other materials, causing fire either by itself or through the release of oxygen or other gases.

PEL - (Permissible Exposure Limit) an occupational exposure limit established by OSHA's regulatory authority.

Pneumoconiosis - condition of the lung in which there is permanent deposition of particulate matter and the tissue reaction to its presence; may range from relatively harmless forms of iron oxide deposition to destructive forms of silicosis.

Ppm - (parts per million) the concentration of a gas or vapor in air.

REL - (Recommended Exposure Limit) maximum exposure limit to an airborne contaminant established by NIOSH; OSHA often subsequently adopts an REL as a PEL.

Reproductive toxin - substances that affect either male or female reproductive systems and may impair the ability to have children.

Sensitizer - chemical that causes a substantial proportion of exposed people or animals to develop an allergic reaction in normal tissue after repeated exposure to the chemical.

Silicosis - disease of the lungs (fibrosis) caused by the inhalation of silica dust.

Transplancental - agent that causes physical defects in the developing embryo.

Twa - (time-weighted average) exposure is the airborne concentration of a material to which a person is exposed, averaged over a total exposure time - generally the total workday (8 - 12 hours).

Vapor - gaseous form of a solid or liquid substance as it evaporates.

Table 1 – Common dental products classified as regulated hazardous waste

Table 1

Figure 1 – Pictograms for use under the Globally Harmonized System for Hazard Communication.

Figure 1

Figure 2 – Sample Inventory Form

Figure 2

COST: $0
PROVIDER: American Dental Assistants Association
SOURCE: American Dental Assistants Association | May 2020

Learning Objectives:

  • Describe the role of OSHA in regulating safe use of chemicals in the workplace and the required components of a written Hazard Communication Program.
  • Discuss types of hazardous wastes and the role of the Safety Data Sheet in identifying hazards associated with specific chemicals or chemical compounds
  • Review training requirements of the Hazard Communication Standard and procedures to ensure compliance with hazardous waste and hazard communication regulations.


The author reports no conflicts of interest associated with this work.

Queries for the author may be directed to justin.romano@broadcastmed.com.