Immediate first aid should be given to any cut or abrasion that occurs at a wastewater treatment facility. A physician should treat more serious injuries. Proper sampling techniques should prevent breakage and spillage. Sample bottles should have a wide mouth opening and, whenever possible, should be plastic. If glass containers are required, the glass should be coated with plastic. Lids for bottles should be tight fitting. Bottles and lids should be cleaned after each use with squirt bottles and paper towels. Carriers for sample bottles should be compartmentalized to prevent breakage, and sampling stations should be hosed down to wash away pathogens that may be present due to spillage or leaking bottles.
Protective clothing consists of uniforms, shoes or boots, masks, gloves, and goggles.
Protective clothing remains at the wastewater treatment facility and prevents wastewater personnel from bringing pathogens home. Protective clothing should be washed, dried, and stored at the wastewater treatment plant or cleaned professionally. Separate lockers should be provided for work clothes and street clothes.
Gloves – Wear appropriate gloves at each work site: elbow-length gloves may be necessary; never submerge top of glove; wash or dispose of gloves after use; wash hands immediately after work when gloves cannot be used
Goggles – Protect eyes from pathogens in aerosols and sust; wash goggles after use
Masks – Prevents inhalation of pathogens in aerosols and dust; wash goggles after use
Uniforms – Leave uniforms at work; use separate lockers for work and street clothing; wash work uniforms at work or use professional service; use bleach on heavily soiled uniforms
Safety records should be maintained for all wastewater personnel. The records should include information addressing accidents, immunobiologicals, major and minor illnesses, and training.
Training should provide information regarding the hazards of pathogens found in wastewater, areas of significant exposure to pathogens, and the use of appropriate hygiene measures and protective equipment. Training should also review significant pathogens that are present in wastewater, their transmission and portals of entry, clinical symptoms of gastrointestinal and respiratory tract infection, and available immunobiologicals
Proper ventilation helps to reduce the risk of infection from pathogenic agents including allergens and toxins by reducing their numbers. Pathogenic agents are present in higher concentration in poorly ventilated areas as compared with outside areas and properly ventilated areas. Areas of poor ventilation usually are bar screens, grit chambers, lift stations, sludge dewatering facilities, wet wells and manholes.
There are various chemical hazards that exist in the collection system. Some of these hazards are addressed below.
Most common odorant
Produced by anaerobic bacteria
Gaseous form of sulfuric acid (H2SO4)
Specific gravity of 1.19
More persistent gas
Odor recognition at 10 PPB
Hydrogen sulfide and water mix to create sulfuric acid
Less than 100 PPM:
* Eye and nose irritation
* Bronchial problems
Greater than 100 PPM:
* Destroys sense of smell
* Loss of concentration
Greater than 500 PPM:
* Brainstem toxicity
* Heart problems
* No treatment
DEATH in a single breath
Carbon Dioxide (CO2)
* At 1% concentration of carbon dioxide CO2 (10,000 parts per million or ppm) and under continuous exposure at that level, such as in an auditorium filled with occupants and poor fresh air ventilation, some occupants are likely to feel drowsy.
* The concentration of carbon dioxide must be over about 2% (20,000 ppm) before most people are aware of its presence unless the odor of an associated material (auto exhaust or fermenting yeast, for instance) is present at lower concentrations.
* Above 2%, carbon dioxide may cause a feeling of heaviness in the chest and/or more frequent and deeper respirations.
* If exposure continues at that level for several hours, minimal “acidosis” (an acid condition of the blood) may occur but more frequently is absent.
* Breathing rate doubles at 3% CO2 and is four times the normal rate at 5% CO2.
* Toxic levels of carbon dioxide: at levels above 5%, concentration CO2 is directly toxic. [At lower levels we may be seeing effects of a reduction in the relative amount of oxygen rather than direct toxicity of CO2.]
Symptoms of high or prolonged exposure to carbon dioxide include:
Increased heart rate
Visual and hearing dysfunctions
Exposure to higher levels may cause unconsciousness or death within minutes of exposure.