May 2008, Vol. 20, No.5

Safety Corner

Treatment, Safety Start at the Headworks

John W. Bannen

An analysis by the International Occupational Safety and Health Information Centre (Geneva) found that wastewater treatment operators encounter no fewer than 15 accident hazards, three physical hazards, four chemical hazards, three biological hazards, and three ergonomic and psychosocial hazards in the course of their daily duties. The injury rate for workers in the wastewater treatment industry in 2006 was 5.2 injuries per 100 workers, according to the U.S. Bureau of Labor Statistics. That’s 15% higher than the national average of 4.4 per 100 workers. Significant operation and maintenance activities occur at the headworks, so it is fitting to address safety concerns specific to this area.

While the configuration and equipment installed in the headworks differ from one wastewater treatment plant to another, the common link of hazards remains. These hazards are present as a matter of the task to be performed, proximity to equipment, being in a hazardous environment, or some combination of these.

I often share with my students this sentiment: “Everything starts with the job at hand. How we accomplish the job and whether we complete the job safely is how we define the success of the job.” Safety must be an integral part of the job planning process. When asked what the acronym SOP stands for many would answer standard operating procedure. However, safe operating procedure fits well as an alternative definition.

Using a job hazard analysis (JHA) is a proven means of preventing injuries. A JHA breaks a job into sequential steps; analyzes each step; identifies any hazards; and states procedures, equipment, or other control measures to keep workers from injury.

Many computerized maintenance-management systems can automate JHAs. JHAs help employees view safety as a part of every task by increasing awareness of hazards and the control measures used to mitigate them.

A worker’s mere presence at the headworks may be hazardous. The equipment in use may present electrical, contact, noise, or other hazards, depending on the type of treatment. Environmental hazards may develop from noxious odors, toxic chemicals, or pathogenic organisms present in the wastestream.

Some hazards are recognized using the “hot stove” methodology. Think about deciding whether to touch a hot stove. The stove provides a warning. You can feel the heat and know that touching it will burn you. The stove is consistent, so you don’t need to guess whether the hot stove will burn; it always burns. Applying this methodology to the headworks, one could see that a comminutor just destroyed a piece of wood and then imagine what it would do to hands or feet. As long as the comminutor is rotating, it can cause injury, so lockout–tagout procedures should be used when performing maintenance and service.

Possibly the most hazardous situation operators face occurs when there is a combination of multiple hazards. We can address this by looking at a typical permit-required confined-space entry of a tank or channel at the inlet of the plant. Simply mention “confined space” and we can readily list physical hazards of falling, environmental hazards of oxygen deficiency, and toxic atmospheres of hydrogen sulfide.

Several questions arise:

  • Are you entering a nonpermit space and associate the term nonpermit with nonhazard, thereby neglecting to recognize fully the fall hazard present?
  • Does the task involve hot work or equipment that must be locked out, tagged out, or blocked out?
  • What is the condition of your equipment?

Some answers can be found in new guidance documents. In 2007, the American National Standards Institute (Washington, D.C.) released a new fall protection standard (Z359.1-2007), which includes changes to fall-arrest equipment used in occupational and nonoccupational activities. Equipment used during permit-required confined-space entries, such as self retracting lifelines, full-body-style harnesses, and personnel hoists, are addressed, as well as defining roles and responsibilities of personnel involved in fall-protection systems.

If safety starts at the headworks and safe work practices multiply like the bacteria in our wastewater treatment processes, imagine the safety culture — no pun intended — that would be seen by the time we reach the effluent channels.

John Bannen is the senior client service representative at Workplace Safety Specialists (Mesa, Ariz.).

John Bannen is the senior client service representative at Workplace Safety Specialists (Mesa, Ariz.).