Be careful while excavating

 At 8:30 a.m. on August 1, 2020, Employees #1, #2, and #3, employed by a electrical services company in the telecommunications field, were working on a multi-employer construction project at the intersection of two streets. They were potholing to locate underground utility lines, with the aim to then bore in a new fiber optic line under the intersection. After finding what they thought was over-pour from the concrete curb, they used a Ring-o-matic Vacuum Excavator to excavate over top of the concrete. They then used a jackhammer on the concrete. The jackhammer bit made contact with a 12,470-volt underground electrical distribution line, and an electric arc explosion occurred. Employees #1 and #2 were killed by electrocution. Employee #3, who was knocked down by the force of the explosion, was transported to the hospital, where he was observed, determined to have no injuries, and released. 

Source:osha.gov

Employee injured by pressurised gas release

 At approximately 9:00 p.m. on August 8, 2006, Employees #1 and #2 attempted to clean out a heat exchanger. The heat exchanger was part of a natural gas piping system in the power generation facility of a wastewater treatment plant. The heat exchanger contained methane and natural gas, pressurized to approximately 300 pounds per square inch. Approximately 200 parts per million of hydrogen sulfide contaminant was present in the natural gas. The natural gas piping system contained two compressors, labeled Compressor A and Compressor B. The heat exchanger that Employees #1 and #2 were to clean out was connected to Compressor B. Compressor B was off and Compressor A was running. Employees #1 and #2 incorrectly assumed that since compressor B was not running, it had already been isolated from Compressor A by a closed valve. However, the valve between compressor A and B was in the "open" position. Employee #2 began removing a plug on the Compressor B heat exchanger, with a pneumatic impact gun, while Employee #1 was standing directly behind him. When the heat exchanger plug was removed, the pressurized natural gas came out of the 0.5-inch plug opening and blew Employees #2 and #1 back. The natural gas did not ignite. Employee #1 was rendered unconscious from the impact. Employee #2 initiated emergency shutdown of the natural gas system and notified other employees about the emergency. An ambulance was called, but neither employee was hospitalized. 

Source:osha.gov

Employee dies after falling into sulphuric acid tank

 At 12:30 a.m. on February 9, 2019, an employee was reaching into a steel pickling tank containing 160 degree Fahrenheit sulfuric acid in order to retrieve a sample of the solution with a hand held plastic syringe.The employee stepped onto the ledge of Pickle Tank #5, used his right hand to reach into the tank to pull the sample while simultaneously holding on to an adjacent hand railing for stability and balance with his left hand. The employee fell into the tank and was submerged. The employee remained in the tank for approximately 1 minute before being recued. He suffered from chemical and thermal burns that resulted in his death. 

Source: osha.gov

Why checking the line up before admitting chemicals is important

 At 8:00 a.m. on March 13, 2019, an employee was working for a manufacturer of basic organic chemicals. He was opening a valve to permit the flow of hexamethylenediamine (HMD). The valve had been actuated to rinse and purge feed lines. It had been left open by the previous shift. The employee forgot to check valve positions before opening the HMD flow valve. He was sprayed with HMD, and he suffered second-degree burns to his groin. He was hospitalized. 

Source:osha.gov

Two Employees Receive Corrosive Burns From Sanitizing

 At 12:00 p.m. on April 19, 2019, Employee #1 and Employee #2 were observing a food establishment's sanitation and cleaning process during an investigation. During the observations of the employees and processes, they used a foaming cleanser, quaternary ammonium, and a spot acid clear for cleaning and sanitizing. A pungent smell believed to be chlorine was being released into the air. Employees #1 and #2 noted that their eyes, skin, and mucosal linings of the mouth, throat, and nose were irritated and burning. Employee #2 measured the quaternary ammonium solution, and it was found to be in excess of 200 PPM, which is higher than recommended levels. Hospitalization was not required. 

Source:osha.gov

Chloride induced stress corrosion cracking of stainless steel thermowells: Potential for ingress of atmospheric moisture

 https://www.hse.gov.uk/safetybulletins/thermowell-corrosion.htm

External chloride stress corrosion cracking of stainless steel

 https://www.hse.gov.uk/safetybulletins/lokring-pipe-connectors.html