Prevention of Legionellosis Associated with Building Water Systems

The American Society of Heating, Refrigerating and Air-Conditioning Engineers (ASHRAE) has developed a draft standard addressing the issue of Legionellosis, a disease caused by infection with the bacterium Legionella pneumophila. The bacterium received this name from the infamous incident that occurred at the 1976 American Legion conference in Philadelphia, where many attendees suffered from an outbreak of a type of pneumonia – resulting in 34 deaths. Legionella pneumophila is spread by the release of small droplets of contaminated water into the air from equipment such as air conditioning cooling towers, showers, misters, and humidifiers. In the Philadelphia Legionnaires’ disease outbreak, the hotel’s cooling tower was identified as the likely source of the disease, although domestic water sources were not evaluated.

Legionnaire’s disease is considered to be fairly common and serious in the United States. It is frequently characterized as an “opportunistic” disease that most frequently attacks individuals with an underlying illness or weakened immune system. The most susceptible include persons who are elderly, smokers, or immuno-suppressed.  Although approximately 1,000 cases are reported annually to the Center for Disease Control, it is estimated that over 25,000 cases occur each year and cause more than 4,000 deaths.

Continue Reading →

Assessing the Need

While visiting a manufacturing client, you discover a noisy and dusty environment.  The employees are wearing dust masks and ear plugs, so you assume the facility is in compliance with Occupational Safety & Health Administration (OSHA) regulations. Right?

OSHA’s Stand

Assigning personal protective equipment (PPE) based on perceived hazards is not  an acceptable practice according to OSHA.  Their Standard 29 CFR 1910.132 requires employers to assess their workplace to determine if hazards are present, or are likely to be present, which necessitate the use of PPE.  Hazards may include impact, penetration, crushing, chemicals, heat, and harmful dust.  Employers are required to use feasible engineering and work practice controls to eliminate and reduce hazards before using PPE to protect their employees.  Hazard sources can include machinery, high temperatures processes, chemical exposures, grinding or other harmful dust emitting sources, welding, falling objects, sharp objects or tools, and rolling or pinching objects. Typical examples of engineering and work practice controls include ventilation, substitution of the hazardous material, isolation of the work process, rotation of workers, wet methods, and housekeeping.  If engineering and work practice controls are not feasible for the work area, then PPE must be used. But caution must be exercised in making this decision, since the use of PPE is typically the last control method that OSHA wants to see utilized. Continue Reading →