April 16, 2011

Biological Agents | Facility Audit

Biological agents include bacteria, viruses, fungi, other microorganisms and their associated toxins. They have the ability to adversely affect human health in a variety of ways, ranging from relatively mild, allergic reactions to serious medical conditions, even death. These organisms are widespread in the natural environment; they are found in water, soil, plants, and animals. Because many microbes reproduce rapidly and require minimal resources for survival, they are a potential danger in a wide variety of occupational settings.

Following are some of the most virulent and prevalent biological agents:
  • Anthrax. Anthrax is an acute infectious disease caused by a sporeforming bacterium called Bacillus anthracis. It is generally acquired following contact with anthrax-infected animals or anthrax-contaminated animal products.

  • Avian Flu. Avian influenza is a highly contagious disease of birds which is currently epidemic amongst poultry in Asia. Despite the uncertainties, poultry experts agree that immediate culling of infected and exposed birds is the first line of defense for both the protection of human health and the reduction of further losses in the agricultural sector.

  • Bloodborne Pathogens and Needlestick Prevention. OSHAestimates that 5.6 million workers in the health care industry and related occupations are at risk of occupational exposure to bloodborne pathogens, including human immunodeficiency virus (HIV), hepatitis B virus (HBV), hepatitis C virus (HCV), and others.

  • Botulism. Cases of botulism are usually associated with consumption of preserved foods. However, botulinum toxins are currently among the most common compounds explored by terrorists for use as biological weapons.

  • Foodborne Disease. Foodborne illnesses are caused by viruses, bacteria, parasites, toxins, metals, and prions (microscopic protein particles). Symptoms range from mild gastroenteritis to life-threatening neurologic, hepatic, and renal syndromes.

  • Hantavirus. Hantaviruses are transmitted to humans from the dried droppings, urine, or saliva of mice and rats. Animal laboratory workers and persons working in infested buildings are at increased risk to this disease.

  • Legionnaires' Disease. Legionnaires' disease is a bacterial disease commonly associated with water-based aerosols. It is often the result of poorly maintained air conditioning cooling towers and potable water systems.

  • Molds and Fungi. Molds and fungi produce and release millions of spores small enough to be air-, water-, or insect-borne which may have negative effects on human health including allergic reactions, asthma, and other respiratory problems.

  • Plague. The World Health Organization reports 1,000 to 3,000 cases of plague every year. A bioterrorist release of plague could result in a rapid spread of the pneumonic form of the disease, which could have devastating consequences.

  • Ricin. Ricin is one of the most toxic and easily produced plant toxins. It has been used in the past as a bioterrorist weapon and remains a serious threat.

  • Severe Acute Respiratory Syndrome (SARS). Severe acute respiratory syndrome (SARS) is an emerging, sometimes fatal, respiratory illness. According to the Centers for Disease Control and Prevention (CDC), the most recent human cases of SARS were reported in China in April 2004 and there is currently no known transmission anywhere in the world.

  • Smallpox. Smallpox is a highly contagious disease unique to humans. It is estimated that no more than 20 percent of the population has any immunity from previous vaccination.

  • Tularemia. Tularemia is also known as "rabbit fever" or "deer fly fever" and is extremely infectious. Relatively few bacteria are required to cause the disease, which is why it is an attractive weapon for use in bioterrorism.

  • Viral Hemorrhagic Fevers (VHFs). Along with smallpox, anthrax, plague, botulism, and tularemia, hemorrhagic fever viruses are among the six agents identified by the Centers for Disease Control and Prevention (CDC) as the most likely to be used as biological weapons. Many VHFs can cause severe, life-threatening disease with high fatality rates.

April 13, 2011

Ionizing Radiation | Facility Audit

Ionizing radiation sources can be found in a wide range of occupational settings, including health care facilities, research institutions, nuclear reactors, and their support facilities, nuclear weapon production facilities, and other various manufacturing settings, just to name a few. These radiation sources can pose a considerable health risk to affected workers if not properly controlled.

Although ionizing radiation has been used in workplaces since 1896, its use has grown significantly in recent years. For example, the use of X-ray equipment to inspect luggage, packages, and other items has become very widespread. Currently, ionizing radiation is also used to neutralize harmful biological agents, including anthrax, as well as microorganisms in certain food.

There are also many common uses of ionizing radiation in manufacturing and construction. Ionizing radiation is used, for example, in inspecting welds, measuring the thickness of microelectronic wafers, developing polymers in the rubber and plastics industries, and measuring and inspecting the quantity and quality of goods produced.

What is Ionizing Radiation?
Ionizing radiation is radiation that has sufficient energy to remove electrons from atoms. In this section, it will be referred to simply as radiation. One source of radiation is the nuclei of unstable atoms. For these radioactive atoms (also referred to as radionuclides or radioisotopes) to become more stable, the nuclei eject or emit subatomic particles and high-energy photons (gamma rays). This process is called radioactive decay. Unstable isotopes of radium, radon, uranium, and thorium, for example, exist naturally. Others are continually being made naturally or by human activities such as the splitting of atoms in a nuclear reactor. Either way, they release ionizing radiation. The major types of radiation emitted as a result of spontaneous decay are alpha and beta particles, and gamma rays. X-rays, another major type of radiation, arise from processes outside of the nucleus.

Alpha Particles
Alpha particles are energetic, positively charged particles (helium nuclei) that rapidly lose energy when passing through matter. They are commonly emitted in the radioactive decay of the heaviest radioactive elements such as uranium and radium as well as by some manmade elements. Alpha particles lose energy rapidly in matter and do not penetrate very far; however, they can cause damage over their short path through tissue. These particles are usually completely absorbed by the outer dead layer of the human skin and, so, alpha emitting radioisotopes are not a hazard outside the body. However, they can be very harmful if they are ingested or inhaled. Alpha particles can be stopped completely by a sheet of paper.

Beta Particles
Beta particles are fast moving, positively or negatively charged electrons emitted from the nucleus during radioactive decay. Humans are exposed to beta particles from manmade and natural sources such as tritium, carbon-14, and strontium-90. Beta particles are more penetrating than alpha particles, but are less damaging over equally traveled distances. Some beta particles are capable of penetrating the skin and causing radiation damage; however, as with alpha emitters, beta emitters are generally more hazardous when they are inhaled or ingested. Beta particles travel appreciable distances in air, but can be reduced or stopped by a layer of clothing or by a few millimeters of a substance such as aluminum.

Gamma Rays
Like visible light and x-rays, gamma rays are weightless packets of energy called photons. Gamma rays often accompany the emission of alpha or beta particles from a nucleus. They have neither a charge nor a mass and are very penetrating. One source of gamma rays in the environment is naturally occurring potassium-40. Manmade sources include plutonium-239 and cesium-137. Gamma rays can easily pass completely through the human body or be absorbed by tissue, thus constituting a radiation hazard for the entire body. Several feet of concrete or a few inches of lead may be required to stop the more energetic gamma rays.

X-rays are high-energy photons produced by the interaction of charged particles with matter. X-rays and gamma rays have essentially the same properties, but differ in origin; i.e., x-rays are emitted from processes outside the nucleus, while gamma rays originate inside the nucleus. They are generally lower in energy and therefore less penetrating than gamma rays. Literally thousands of x-ray machines are used daily in medicine and industry for examinations, inspections, and process controls. X-rays are also used for cancer therapy to destroy malignant cells. Because of their many uses, x-rays are the single largest source of manmade radiation exposure. A few millimeters of lead can stop medical x-rays.

April 10, 2011

Compressed Gas, Equipment, Fire and Explosions | Facility Audit

Compressed Gas and Equipment

Hazards associated with compressed gases include oxygen displacement, fires, explosions, and toxic gas exposures, as well as the physical hazards associated with high pressure systems. Special storage, use, and handling precautions are necessary in order to control these hazards.

Some common troublespots associated with compressed gas include:
  • Improper handling of cylinders. Compressed gas cylinders require careful handling to prevent damage. When handling cylinders, move cylinders (securely fastened, in as near an upright position as possible) on special hand trucks. Take precautions not to drop or bang cylinders together. Also, ensure workers know not to roll, drag, or slide cylinders and never use cylinders as rollers or supports. Workers should also never lift cylinders by their caps or use magnets to lift cylinders. Cradles or platforms can be used to lift cylinders only if the cylinder was manufactured with lifting attachments.

  • Compressed gas cylinders not clearly identified. Never rely on cylinder color for identification, as this can vary with the supplier. Similarly, don't rely on cap labels as these are interchangeable.

  • Incorrect tools. Make sure you use only tools provided by the cylinder supplier to open or close a valve. Always be familiar with the supplier's guidelines and instructions.

  • Unsafe cylinders. Employers need to determine that compressed gas cylinders under their control are in a safe condition to the extent that this can be determined by visual inspection. Some items to look for are leaks, bulges, defective valves or safety devices, physical abuse, fire/heat damage, and detrimental rusting or corrosion. Cylinders with defects must not be used unless properly repaired and requalified. Employers must return defective cylinders to the supplier.

Fire and Explosions

Workplace fires and explosions kill 200 and injure more than 5,000 workers each year.

Fire is among the most deadly of workplace hazards and the most preventable of accidents. Because of the serious danger of fire, it's to your benefit to know about fires and what to do should a fire erupt.

OSHA regulates several aspects of fire prevention and response. Emergency planning, fire prevention plans, and evacuation that would need to be done in the event of a serious fire are addressed in the OSHA standard, §1910.38. In addition, the provision of fire extinguishers and other protection is addressed in §1910.157.

It takes a certain combination of three elements — oxygen, an ignition source, and fuel — to start a fire. Without one of these elements in the proper amount, the fire will not start, or if it has already started, will go out. Fire can be represented by a simple equation:
  • Fire = Ignition + Fuel + Oxygen

Chemical Fires
Many of the thousands of chemicals in use in the workplace are both highly toxic and highly volatile. Extreme caution must be used to prevent and fight fires resulting from chemical spills and accidents. Chemicals can cause serious injuries through physical (fire or explosion) or health (burns or poisons) hazards. Chemicals are classified by the inherent properties that make them hazardous.
  • Flammable — these chemicals catch fire very easily; hazards include property damage, burns and injuries that result when toxic and corrosive compounds are released into the air.

  • Reactive — a reactive material is one that can undergo a chemical reaction under certain conditions; reactive substances can burn, explode, or release toxic vapor if exposed to other chemicals, air or water.

  • Explosive — an explosive is a substance which undergoes a very rapid chemical change producing large amounts of gas and heat; explosions can also occur as a result of reactions between chemicals not ordinarily considered explosive.

Common Fire Hazards
Below are some areas to look at for identifying and preventing fire hazards:
  • Smoking areas;

  • Heating, ventilating, and air conditioning systems, including their pipes, switches, wiring, and boiler controls;

  • Electrical equipment, including wiring and controls and extension cords;

  • Static electricity;

  • Forklift fueling and servicing;

  • Hot work;

  • Flammable and combustible liquids and gases;

  • Storage areas; packaging, including cardboard, excelsior, foam compositions, and paper;

  • Waste removal.