Personal Protective Equipment

Assigned Protection Factor, or APF, means the workplace level of respiratory protection that a respirator or class of respirators is expected to provide to employees when the employer implements a continuing effective respiratory protection program. Maximum Use Concentration, or (MUC), means the maximum atmospheric concentration of a hazardous substance from which an employee can be expected to be protected when wearing a respirator, and is determined by the assigned protection factor (APF) of the respirator or class of respirators and the exposure limit of the hazardous substance. The Maximum Use Concentration is usually determined mathematically. The formula requires you to multiply the assigned protection factor signed protection factor specified for a respirator by the permissible exposure limit, short-term exposure limit, ceiling limit, peak limit, or any other exposure limit.

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Penetration is the movement of chemicals through materials on a larger scale. This happens frequently in the workforce through holes created and tears in workers Personal Protective Equipment (or PPE).

Permeation is the process where a chemical dissolves in or is able to move through a barrier, this is done on a molecular scale. This often happens at such a small scale there is often no visible evidence of the chemicals permeating PPE and workers are completely unaware until they are harmed. Degradation is when the presence of a chemical has the ability to physically deteriorate the material of the PPE and its physical properties are changed due to the exposure.

There are two main types of respirators, Air Purifying Respirators, or APR, and Supplied Air Respirators, (SAR). 

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Air Purifying Respirators are where the air the w

orkers breathe is purified using cartridges or canisters. This group of respirators are further divided into three categories: particulate, gas & vapor, and combination. Particulate respirators are intended to catch particulates in the air such as dusts, fumes, mists, and other vapors. Combination respirators normally are used in areas that contain risks of both particulates and gases and vapors. Supplied Air Respirators are respirators where the air workers breathe is supplied from another source that is uncontaminated. There are separated into three categories. The categories are airline, combination, or self-contained breathing apparatus, or SBCA. Airline Respirators use a lightweight airline hose to deliver clean, breathable air from an uncontaminated source. Combination respirators have an auxiliary self-contained air supply that can be used if the primary supply fails. Self-Contained Air Breathable Air respirators consist of a wearable, clean air supply pack and normally used when there is a short time need to enter and escape from spaces that are or may be immediately dangerous to life.

Qualitative fit tests are based on the human senses smell, taste, or overall reaction to the chemical in order to determine if there is any contamination into the respirator piece. Quantitative fit tests measure the actual concentration of the contamination. A Written hazard assessment is used to identify a hazard in a workplace. For example, to assess the need for masks needed for workers who work in coal mines.

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Noise

Noise Reduction Ratings, or NRR’s, are units of measurement that are used to help determine the usefulness of hearing protection devices and to minimize sound exposure inside a workplace or working environment.  These ratings are shortened to Db, a term used to categorize the power or density inside a sound. Ear plugs are made at different levels to accommodate for high sound exposure and ratings. Hearing protection equipment has to be tested and accepted by the American NationalStandards Institute (ANSI),  and also has to be in compliance with the Occupational Safety and Health Administration (OSHA). The Noise Reduction Rating is rated on a positive sliding scale that justifies the higher the number, the more capability of the device for noise reduction.

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The Noise Reduction Rating is calculated by taking the noise exposure of the environment in decibels, subtracting by seven, then dividing by two. For example, if you are working in an environment where the noise of exposure is 90db and you are wearing ear plugs with an NRR of 33dB, the calculation would be 33-7 = 26. 26/2 = 13. That means your new noise exposure level would be 77db. Multiple reduction devices can be worn at the same time to reduce your exposure.

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Standard Threshold Shift, or STS, is the occupational noise exposure standard. It is known as a change in hearing threshold, relative to the baseline audio of the employee. It equates to a hearing loss of 10db or more at 2000, 3000, and 4000 hz or Hertz, in either ear. Over time, someone with STS will eventually have a hard time understanding people talking to them and have a hard time generally hearing other sounds in their atmosphere. Through aging, Standard Threshold Shift usually occurs naturally. Technically not naturally, but through the course of life. Having hands on jobs increases your likelihood of hearing damage because you are exposed to loud sounds on a more regular basis for longer amounts of time over the course of your career, jumpstarting hearing loss. This is why older people have a tougher time hearing than younger people do.

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an exchange rate is the increase of decrease in decibels corresponding to twice or half the noise fdon.e this rate is used to calculate the time that an employee is allowed to be in a particular environment. OSHA uses an exchange rate of 5db. For example, if the exchange rate is 5db, 90db produces twice the noise dose that 85 db produces when the exposure is constant.

To best illustrate different sounds, I decided to measure both high and low noise environments.  I first measured the floor in my apartment, because I was the only person home and it was very quiet. For the high noise environment measurement, I used the Pigskin Bar on Court street while I was working one night. The screenshots for both are attached below. Potential adverse effects that may occur by staying in the Pigskin for extended amounts of time, and those would be temporary hearing loss and possibly permanent hearing loss.

Benzene Sampling

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Air Testing is used to test and analyze the air in a workplace. This could be in a construction zone, office, government building, school, mall, or anywhere else where business takes place or people live.  Although air testing has not always existed, it is now essential in our day to day lives because of all of the chemicals and pollutants that exist today that are hazardous to our health. Poor air quality can lead to unfortunate health changes in the environment and in individual’s bodies. Results for exposed people can range from sore eyes, burning in the nose and throat, nausea and headaches. Extreme results could be allergies, heart disease, cancer and other longer-term diseases/results. Employers who do not comply with air quality standards get in legal trouble.

Molds, bacteria, asbestos, dust, gases and fumes, pesticides and other chemicals are examples of common air pollutants found in buildings in workplaces.

Pump Callibration is the process of using a metering instrument to determine the airflow rate created by the sample collector. Callibration of the flow of a sample through the sampling is important and needs thoroughly checked before and after each sample. In class, we did a benzene sampling test. We used the formula included in the associated powerpoint to calculate our answer, and after the math was done, our answer equaled 14.7, or two liters per minute. 0.75parts per million (PPM) is less than the occupational exposure limit, meaning it was in acceptable amounts in our classroom. We were not overexposed to benzene in class.

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The “breathing zone” is technically the five to ten inch radius surrounding a worker’s nose and mouth. This area is specifically targeted because the mouth and nose are the modes of entryway through inhalation and ingestion.

As mentioned above, some substances will not show effects for years after exposure. For example, asbestos can linger in the inhalant’s lungs and eventually cause irreversible damage to their health and life longevity.  

Occupational exposure limit, or OEL, is determined by OSHA. Occupational Safety and Health Administration, or OSHA, is a part of the United States Department of Labor. The OSHA administrator is the Assistant Secretary of Labor for Occupational Safety and Health. OSHA deals with assuring the health standards of the workforce by setting and enforcing standards to protect people. Other tasks involve training, outreach, educating and assisting the workforce.

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On the Center for Disease Control and Prevention’s webpage is listed the National Institute for Occupational Safety and Health, (NIOSH) . There are different methods to testing substances in the workplace’s air, surfaces, and blood and urine of the workers there.

When testing, the flow rate, sample’s stability and sample itself impact the outcome of the test. Flow rate is the volume of fluid which passes per unit of time. Sample stability is the capability of a material to retain the initial property of a measured constituent for a period of time within a certain time period. Instability is present when a change occurs in one of the measurements taken.

Airborne Hazards

Airborne Hazards

When gas is inhaled, the body uses the lungs and the respiratory system to process it. The respiratory tract has multiple parts that consist of three regions: the upper, middle, and lower regions. Naturally, each region has a different function. The respiratory system begins with the upper part. This is called the nasopharynx region or the head region.  includes the nasal cavity and soft palate, both of which are connected to the lower part by the pharynx, (also known as the throat). Leading down the larynx brings you the tracheobronchial region. This region includes the trachea, bronchi and lungs. The nasopharyngeal region removes large particles, the tracheobronchial region moves air to the pulmonary spaces. The pulmonary, or alveoli region. The pulmonary region takes care of the gas exchange with the lungs through respiration.

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The mucociliary elevator is an organ in the body that humidifies gases and defends the lungs from infection of particulate, chemical and microbiologic matter. This organ consists of single layer, stacked cells that appear to be in different layers, separated into two parts: the mucus-producing goblet cells and the ciliated epithelium. The cilia on the epithelium are pulsating constantly, pushing mucus up and out into the throat. The mucocilliary elevator catches infectious microorganisms and by getting them stuck in the mucus, defending the body from infections.

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Airborne Hazards are harmful air pollutants that when inhaled, can lead to the development of cancer and other diseases.

There are four ways to intake these pollutants: inhalation, ingestion, injection and absorption. Airborne hazards are a concern for many different workplaces. To reduce the chances of contamination through injestion and inhalation, a dust mask or respirator is suggested to be worn in the concerned workplace. Wearing these will help reduce the amounts of dust, gases, biohazards, fumes or other particulates that can make an impact on the body.

Unrelated to wearing a mask or not, different people’s bodies react differently to airborne hazards. The extent of the effect is having can be less or more depending on how long the person contacted was exposed to it, how much they were exposed, the concentration of the hazard in the air, and whether they were wearing a type of protection or not. The negative health effects are not always immediate, sometimes effects take years or even decades to become apparent.

There are 5 airborne hazardous materials that potentially could invade the respiratory tract. Gas, vapor, dust, mist, and fumes, in order from smaller to largest, respectively.

Lung impairments fall into two categories: Obstructive lungimpairments and restrictive lung impairments.  Obstructive lung impairments make it more difficult to exhale completely from the lungs. Examples of obstructive lung disease are emphysema, asthma, chronic bronchitis, and cystic fibrosis. Restrictive lung impairments make it difficult to fully expand their lungs and chest to fill them with air. Examples of restrictive lung disease are obesity, autoimmune disease, scoliosis, idiopathic pulmonary fibrosis and interstitial lung disease. The same central condition occurs for both: shortness of breath.

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Toxicology

Toxicology is defined by Merriam-Webster Dictionary as a science that deals with poisons, their effects, and the problems associated with them. These problems can include clinical, industrial and legal related problems. Basically, toxicology studies poisonous chemicals and reactions to them; therefore, a person who studies these poisons is considered a toxicologist. The different branches of toxicology include clinical toxicology, pharmacology, forensics, and OSHA aspects.

The chemicals studied by toxicologists have four major routes of entry into the human body. These routes include inhalation, absorption, ingestion, and injection. Inhalation is to be breathed in through the lungs. Absorption is through skin contact. Ingestion is when something is eaten through the mouth. And injection is typically performed with a needle into the skin.

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Inhalation is the most common entryway for chemicals in the workplace. Injection is less likely to happen unintentionally at the workplace given how specific the entryway is.  

Irrelevant of how the chemical or drug entered the body, the distribution of the chemical into the body is the same. To remove the hazard from the area, try to isolate the hazard and provide a local exhaust. If that is not possible, help the exposed workers fewer shifts to minimize impact.

Biotransformation is the chemical changes made by an organism on a chemical compound. There are two different phases involved in biotransformation. Phase I involves oxidation, reduction and hydrolysis reactions. Oxidation is when electrons are released (ex: rust). Reduction is when oxygen is removed from the compound, and hydrolysis is a reaction involving a bond breaking due to water. This occurs mainly between an ion and water molecules. These three reactions make up phase I work to convert the original compound into a more polar metabolite. Phase II involves conjugation reactions. These reactions result in the formation of water-soluble compounds. Different ages of life change which phase the body metabolizes with typically.

The medical definition of Dose-Response explains that dose-response is the pattern of which your body responds to varying dosages of a chemical or drug. For example, nicotine, cocaine, morphine, and other amphetamines dose-response curves are similar.

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In toxicology, the median lethal dose is 50%, commonly abbreviated as LD50. This percentage is referring to the time when 50% of the animals in a group of test animals dies. It is a method to measure the acute toxicity of a material. This is not to be confused with LC50, meaning lethal concentration in the air or in water. Chemicals have a broad range of effects on our health. Toxicity tests are useful in many situations to help prevent overexposure.

Toxicity is influenced by many different factors. The dosage, exposure route, and absorption ability influence toxicity, as well as the injesting person’s life stage, metabolism, gender, health, and nutritional status. Pregnant women’s toxicity is influenced differently than that of a non-pregnant woman as well.

In some cases, reactions to chemicals or drugs are completely abnormal and unpredicted, (formally called idiosyncratic responses). This can happen because of genetic predispositions or immune system issues or anything in between. These reactions could be abnormally extreme or the opposite. 

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