ON THE WAKE OF THE SANTA PAULA EXPLOSION, MANY WASTEWATER TREATMENT PLANTS DO NOT COMPLY WITH THE 2012 NFPA STANDARD 820
There have been infrequent fire or explosion incidents at wastewater treatment plants; infrequent but sever, just like the one at the Santa Paula plant. The purpose of the NFPA 820 standard is to provide a degree of fire and explosion protection and reduce or eliminate the effects of fire or explosion at wastewater collection, transportation, and treatment facilities.
Another purpose is to reduce or eliminate the effects of fire or explosion by maintaining structural integrity, controlling flame spread and smoke generation, preventing the release of toxic products of combustion, and maintaining serviceability and operation of the facility.
NFPA 820 establishes minimum requirements for protection. The standard applies to new installations and to additions or modifications to existing facilities. It should be used by designers/owners in risk assessment for existing facilities.
Hazardous Area Definitions
▪ Class I, Div 1: Where ignitable concentrations of flammable vapors are present under normal operation conditions
▪ Class I, Div 2: Where ignitable concentrations of flammable vapors are present under abnormal operating conditions
▪ Class II, Div 1: Where ignitable concentrations of combustible dusts are present under normal operating conditions
▪ Class II, Div 2: Where ignitable concentrations of combustible dusts are present under abnormal operating conditions
The problem is that NFPA 820 has not been widely adopted due to the costs associated in complying with its requirements. Furthermore, plants built prior to 1990 typically have areas that do not comply with NFPA 820. Issues at existing plants include: no physical separation between a classified location and unclassified location; gas tight partition required between classified location and unclassified location. Areas at existing plants that should be classified as Class I, Div 2 are not classified at all, creating fire and explosion hazards. Storage areas for hazardous chemicals used in the treatment of the wastewater (such hydrogen peroxide, acids, bases, etc.) need to properly classified and separated from other areas.
Chemical and other Health Risks to Workers at Wastewater Treatment Plants
Working in the field of wastewater treatment can be a hazardous profession. We recently requested information from the National Institute for Occupational Safety and Health (NIOSH) in regards to health & safety for wastewater workers. In short, NIOSH stated that there has not been a lot of research on the health of wastewater workers and that NIOSH continues to study this issue.
The following are some suggestions that may help workers in this field to stay healthy on the job. These are only suggestions and they are not intended to be policy and are not all inclusive. Depending on your circumstances and location, you may be subject to laws, rules or regulations in regards to health and safety for wastewater workers. It is the responsibility of the facilities and workers to review their own situations and apply the appropriate safeguards to assure a safe working environment. Additional safeguards and consideration beyond those discussed in this document and related attachments may apply to your facility. Review and updating of safety policies needs to occur on a continuing basis.
Water borne disease is a concern for wastewater workers. Currently (as of July 1, 1998) The National Institute for Occupational Safety and Health (NIOSH) has made no official recommendations regarding vaccinations for workers who contact sewage. NIOSH does point out that sewage workers, like all adults, should be current on their tetnus-diphtheria immunization. NIOSH also pointed out that there is continuing study on hepatitis A vaccinations for sewage workers. NIOSH (along with several other agencies and researchers) do acknowledge that there may be some potential risk for water borne pathogens and they further state that one of the best defenses against water borne disease for sewage workers is to practice good hygiene and good house keeping.
Workers at wastewater facilities should wash their hands frequently with anti-bacterial soap. Be sure to wash thoroughly and scrub under nails with a brush. Especially be sure to wash up before eating, smoking or drinking.
Open cuts or wounds should be protected, be sure to replace contaminated dressings.
Avoid direct contact with wastewater, always wear rubber gloves and protective clothing when working with wastewater.
Do not wear contaminated or soiled clothing, wash work clothes regularly to remove contaminants. It is suggested that work clothing for wastewater workers be washed on-site, it IS NOT recommended to bring sewage contaminated clothing home. Let your work clothing (and work boots) remain at work. Bringing the contaminated clothing home may expose other family members to pathogens. It is also recommended that you take a shower at the end of your shift.
In spite of our best efforts, at times thing may go wrong that result in copious amounts of wastewater or wastewater residues spewing forth onto workers. If you get sprayed or soaked down with sewage or sewage residues, change clothes and take a shower.
Keep your fingernails short and DO NOT bite your nails!
DO NOT stick your fingers or hands in your mouth, nose, eyes or ears.
One of the biggest dangers faced by workers in wastewater systems is ‘Confined Spaces". There are many dangers associated with confined spaces with one of the primary hazards being atmospheric. The potential for deadly environments exists in confined space areas. Workers need to be able to identify and deal with hazards associated with confined spaces. Examples of confined spaces in wastewater system include (but are not limited to), manholes, sewers, pipelines, storage tanks, wetwells, digesters and pump stations. Additionally, atmospheric hazards may exist in other areas where wastewater or wastewater residues are processed. The use of personal gas detection equipment while working in a wastewater facility is recommended. It is recommended that wastewater workers obtain and follow all OSHA requirements for working in confined spaces.
As mentioned above, atmospheric hazards may exist anywhere in a wastewater treatment system where wastewater or wastewater residues (biosolids) are processed. As a result of the natural decomposition and treatment of wastewater or wastewater residues, gases are produced and or consumed. Examples of the gases produced include methane, hydrogen sulfide, and carbon dioxide. Additionally, oxygen may be displaced or consumed by organisms thus resulting in a oxygen depleted atmosphere. Atmospheric hazards can also come from industrial or commercial sources as well. There are documented cases of gasoline finding its way into sewer systems. The use of fixed or permanent mounted gas detection equipment (in addition to personal gas detection) will protect property and lives. Be sure to calibrate and maintain gas detection equipment as per manufacturers recommendations. Atmospheric and explosion hazards are especially prevalent at facilities that utilize anaerobic digestion in their treatment process. There are several documented cases of treatment facilities exploding and workers being killed as a result of methane explosions at treatment facilities using anaerobic digestion.
Drowning is also a serious threat at wastewater facilities. There are several documented cases of workers and officials drowning in wastewater systems. Extreme currents and process equipment make the wastewater system a deadly environment from the standpoint of drowning. Be sure that there is railing around all process tankage and pits. If you must work inside the railing area, be sure to wear a life line and personal flotation device (PFD). Rescue buoys and throw bags are also a good idea. Be sure to locate rescue equipment in easy to access areas in wastewater systems. Remember, the use of PFD’s is always a good idea when working near waterways.
Traffic hazards can pose threats to workers and motorists alike. Be sure to properly set up traffic zones and controls when working on streets. Additional regulatory requirements may apply especially if digging up a state owned highway.
Collapse of trenches can cause serious injury or death, be sure to utilize proper techniques for trenching and shoring when you are digging.
Call before you dig (PA One Call System). Digging up or rupturing lines such as power lines or gas lines can be hazardous or deadly! Locate all underground utilities before you start to dig. The Pennsylvania One Call System 1-800-242-1776, CALL BEFORE YOU DIG! The PA One Call System notifies all utilities of any excavation work to be performed enabling them to locate and mark their utility lines. PA Act 38 of 1991 requires notification to a one call system three (3) working days prior to the start of any digging.
Chemical hazards are also present at wastewater treatment facilities. In some cases (such as chlorine), the chemical hazard may be deadly. Be sure to read and understand the MSDS for the chemical product you are working with. The MSDS for all products should be easily accessible to both system workers and emergency responders. Be sure to follow all recommendations for personal protective equipment when working with chemical products. Clean up all chemical spills promptly. Depending on the type and quantity of chemical spilled, you may also need to report the spill to your county Emergency Operations Center. Refer to your states emerging response system for more information on reporting requirements for chemicals you have on site. For example, if you have 100 pounds or more of chlorine on site, planning and reporting requirements are triggered. Chemical hazards may also be present at the industries connected to your system. Sewer use ordinances should include provisions to prohibit dangerous substances from entering the sewer systems, spill prevention and containment plans can prevent disasters of this sort from happening. Also, be sure you are familiar with the proper use and maintenance of personal protective equipment and clothing. Using and maintaining equipment such as Self Contained Breathing Apparatus (SCBA) requires training and practice. Using this equipment in a hazardous environment needs to be second nature, a mistake or panic in a dangerous environment could be disastrous!
Falls in wastewater system are a danger as well, the use of fall protection devices can prevent serious injury. Good house keeping can help by removing slipping or tripping hazards.
Fire and explosion in wastewater systems is a concern as well. For more information on this subject it is recommended that wastewater systems obtain a copy of "NFPA 820 Standard for Fire Protection in Wastewater Treatment and Collection Facilities" The National Fire Protection Association (NFPA) is located in Quincy, MA. The NFPA 820 standard can be ordered directly from NFPA. You can find them on the Internet.
There have been many documented injuries from heavy lifting in wastewater treatment facilities. Most equipment found in wastewater systems is quite heavy. Proper technique for lifting objects is necessary to prevent injury. Crush injuries from this equipment is a threat as well.
Develop and integrate a safety program into your work environment. A facility safety officer or safety committee can help to focus on safety and health related issues. While prevention is always the best answer, accidents continue to happen. It is a good idea to follow up after an accident or injury to look at the cause so future accidents can be prevented. Be sure to keep up with the latest regulations or standards as well as changes in safety science that relate to your facility.
Regular medical surveillance (regular physical examination) is a good idea and may even be a necessity especially for workers who are exposed to hazardous materials.
Electrocution or mechanical hazards due to energizing circuits on equipment being repaired or serviced is also a concern. Establish a "Lock Out/Tag Out" procedure when working on process equipment to prevent accidental starting of equipment. Physically locking out the breaker and motor starter prevents these types of accidents. Similarly, valves to process tanks should also be locked to prevent accidental flooding during maintenance.
The wastewater laboratory can present hazards to wastewater workers. Often times, wastewater labs acids or poisonous reagents that must be handled and stored properly. Examples of equipment you may want to have in your lab include, acid storage cabinets, emergency deluge showers, eye wash stations, appropriate fire extinguishers, fire blanket, fume hoods and spill clean up kits. Always wear safety goggles, lab smock and gloves when working in the lab. Eating, smoking or drinking in the lab IS NOT a good idea. Never pipette by mouth as many reagents are corrosive and/or poisonous. DO NOT store food in the same refrigerator with reagents or samples. Clean up all spills promptly using the appropriate materials. All reagents and products in a lab should be clearly labeled.
All facilities should develop plans on how to deal with emergencies. Proper preplanning can save lives and property. Examples of emergency plan topics could include subjects such as fire, explosion, flood, spills into the sewer system, chemical releases, severe weather, medical emergencies, or other natural and manmade disasters. It is a good idea to occasionally test and update plans, especially where plans involve the interaction of several agencies or groups. Voluntary employee emergency information sheets can provide emergency medical workers with valuable information about the injured person (especially if they are unconscious). Medical information is a private matter and needs to be kept confidential. Coordinate where you would keep employee information sheets and the needed information with emergency medical personnel. Chaos, confusion and panic are some of the elements that may accompany an emergency, proper planning can reduce or eliminate tragic circumstances. Emergency planning needs to happen before the emergency occurs! Anticipate and expect the UN-expected.
A proper emergency response program can provide help with emergency planning and training people (hands-on) on the proper use of safety equipment.
CHEMICAL EXPLOSION IN CALIFORNIA. DOZENS WENT TO THE HOSPITAL.
A mysterious chemical mixture burst into flames at a Ventura County waste facility on Tuesday, sending dozens to hospitals for decontamination and emptying homes and businesses for a mile around the plant before the danger eased, authorities said.
A vacuum truck exploded into flames about 3:45 a.m. at the Santa Paula Waste Water Co., spreading about 1,200 gallons of a mysterious waste chemical mixture that contained sulfuric acid and a highly combustible organic peroxide, fire officials said.
"As the liquid began to dry out, the (fire engine) companies on scene noticed that it was very unstable and reactive," Ventura County fire Capt. Mike Lindbery said. "As they stepped on it or tried to move their engine, it would spontaneously ignite under the tire of the engine or their boots."
No burn injuries were reported, but two drivers on a vacuum truck, three firefighters, hospital medical staff and a few nearby residents were washed down or treated for complaints such as breathing problems, red eyes and skin rashes, said Lori Ross, a spokeswoman for the Ventura County Fire Department.
SANTA PAULA (CBSLA.com) — A chemical spill sparked multiple explosions, sickening dozens and forcing nearby residents to evacuate their Ventura County homes on Tuesday.
By late afternoon, investigators were preparing to move in as the toxic smoke had diminished at the Santa Clara Water Waste Co.
Firefighters arrived at the scene about 3:45 a.m. after reports that a vacuum truck had exploded. The truck was sitting in the middle of the facility surrounded by a white substance that was spread by the explosion. When firefighters looked down at their shoes, they saw the material sparking into flames around their feet, and quickly got away ahead of a series of explosions.
Ventura County fire Capt. Mike Lindberry told CBS2′s Randy Paige that the material on the ground was a form of organic peroxide, a highly volatile chemical that burns quickly. He said a big concern was nearby toxic chemicals, including sulfuric acid and other corrosives, that would create extremely hazardous smoke if they caught fire.
“We had acids burning, we had wood, we had everything in the area, rubber on tires and boots burning,” Lindberry said. “The big concern was the fact that if we were to have a large explosion we don’t want people in that area.”
That meant mandatory evacuations for everyone within a mile of the plant, and shelter-in-place orders for everyone within a 3-mile radius, as well as the closure of Highway 126.
Lindberry said putting water on the fire could have caused even bigger problems, including the potential contamination of the nearby Santa Clara River. So firefighters had to wait for it to burn itself out.
At least 37 people were treated for exposure to the volatile chemicals, with most complaining about irritated eyes and throats. All of the injured, except the truck driver, were released.
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