Sunday, February 15, 2015

Confined Space

A confined space is defined as a space that are not necessarily designed for people, but they are large enough for workers to enter and perform certain jobs. Confined and enclosed space operations have a greater likelihood of causing fatalities, severe injuries, and illnesses than any other type of shipyard work. Some examples include: tanks, vessels, silos, storage bins, hoppers, vaults, pits, manholes, or pipelines. OSHA labels these areas as “permit-required confined space,” it is labelled these when they contain a material that has potential to contain a hazardous atmosphere, has walls that converge inward or floors that slope downward and taper into a smaller area which could trap or asphyxiate  an entrant.
Some more general terms to know about confined spaces are as follows. "Acceptable entry conditions" means the conditions that must exist in a permit space to allow entry and to ensure that employees involved with a permit-required confined space entry can safely enter into and work within the space. "Attendant" means an individual stationed outside one or more permit spaces who monitors the authorized entrants and who performs all attendant's duties assigned in the employer's permit space program. "Authorized entrant" means an employee who is authorized by the employer to enter a permit space. "Blanking or blinding" means the absolute closure of a pipe, line, or duct by the fastening of a solid plate (such as a spectacle blind or a skillet blind) that completely covers the bore and that is capable of withstanding the maximum pressure of the pipe, line, or duct with no leakage beyond the plate. "Entry permit (permit)" means the written or printed document that is provided by the employer to allow and control entry into a permit space and that contains the information specified in paragraph (f) of this section. "Entry supervisor" means the person (such as the employer, foreman, or crew chief) responsible for determining if acceptable entry conditions are present at a permit space where entry is planned, for authorizing entry and overseeing entry operations, and for terminating entry as required by this section. 
                To enter a permit-required confined space you first must be properly trained and have the proper permit. You must know the proper procedures before entering and know how and when to exit. Before you can enter the space you must identify any physical hazards, test and monitor for oxygen content, flammability, toxicity or explosive hazards as necessary. If there are such hazards, the employer then would classify the space according to the physical and atmospheric hazards found in it. The four classifications are: Isolated-Hazard Confined Space, Controlled-Atmosphere Confined Space, Permit-Required Confined Space, and Continuous System-Permit-Required Confined Space. The proposed requirements for each type of confined space are tailored to control the different types of hazards. The worker must be wearing the proper fall protection, rescue, air-monitoring, ventilation, and lighting and communication equipment according to entry procedures. While the worker is in the confined space they must be in constant contact at all times with a trained attendant either visually, via phone, or by two-way radio. This enables a quick rescue if anything were to go wrong, or for the attendant to order the worker in the confined space to evacuate and to alert appropriately trainer rescue personnel to rescue entrants when needed.


Sunday, February 8, 2015

UCLA Lab Accident

In Los Angeles December 29th 2008, was the day that Sangji 23 got in a laboratory accident and died on January 16th. Sangji was working on a reaction involving tert-Butyllithium. Tert-Butyllithium is known to ignite spontaneously with air. Patrick Harran was the chemistry professor in charge of Sangji and was upstairs at the time of the accident. Harran had caused the accident through the teachings of improper lab technique and personal protective equipment. Sangji had never been properly trained or even issued a lab coat, she was wearing improper lab dress, a synthetic sweatshirt, instead of wearing a lab coat which is a lot more flammable. This was not the first warning of improper lab techniques, two other students had been burned before and the lab had been issued many citations.
                The university and the DA reached a settlement, in return for admitting responsibility for the lab conditions when Sangji died, for promising to maintain a comprehensive lab safety program, and for setting up a $500,000 environmental law scholarship at Berkeley in Sangjji’s name, prosecutors dropped the charges. However, the case against Harran continued and was sent to trial. Harran faced up to 4.5 years in prison and UCLA could be fined up to $1.5 million. The results of the trail was that Harran had to participate in community service and pay a $10,000 fine. Harran’s punishment was nothing more than a slap on the wrist. This caused a panic throughout the academic community. Many professors don’t see themselves as managers to the students in their graduate help, especially with the high rate of turnover. This case helped to rapidly change the culture of labs throughout colleges in America.
                UCLA after the case achieved a 95% compliance with the personal protective equipment policy. One such improvement is a series of unannounced safety improvements. Though the Environmental Health and Safety department at UCLA made all of these claims, one professor said that this was not true and that earlier that week they had seen students in the lab wearing flip flops and shorts.
Now, there have been many more forceful and frequent training and safety discussions not just at UCLA but at any college with lab work. There has been a shift from a mindset of get through the training now I’m done, to actually paying attention to the training and general safety not only with the students but with the professors in charge as well. The system that had existed for so long, that had tolerated these poor training systems have started being challenged and slowly getting fixed over the years across the country since the accident. Many schools started providing incentives for practicing good safety, some even provided grant money or space that could serve as a reward for the safest labs. Even though colleges could add incentives there should still be strict punishments instructed if a college or a student or a professor breaks any safety rules. Today the UCLA environmental and health safety webpage is one of the most reliable sites for safety rules and protocol.


Sunday, February 1, 2015

Nanotoxicology

Nanotoxicology is the study of nanomaterials and cells, animals, humans, and the environment. Though this is a relatively new study it has shown that these interactions are highly complex and intertwined. Humans have always had exposures to nanosized particles throughout their evolutionary stages, but such exposures have increased dramatically over the last decade from human made sources. Humans have exposure from these particles through: inhalation, ingestion, skin uptake, and injection off engineered nanomaterials.
When inhaled, specific sizes of nanosized particles are efficiently deposited by diffusional mechanisms in all regions of the respiratory tract. The small size facilitates uptake into cells and transcytosis across epithelial and endothelial cells into the blood and lymph circulation to reach potentially sensitive target sites such as bone marrow, lymph nodes, spleen, and heart. Access to the central nervous system and ganglia via translocation along axons and dendrites of neurons has also been observed. Nanoparticles penetrate the skin distribute via uptake into lymphatic channels.
The chemicals properties of a chemical at the nano-level are very different from their properties in high quantities, such as a chemicals half-life or if they will persist in the environment. Could these nanoparticles infect our water supply? It is also hard to predict the effects of nanoparticles on the environment and humans because they are in such small quantities and we do not know yet the effects or presence of bioaccumulation of these particles. Because of this is makes it very hard to set regulations on the use of nanotechnology.
These nanoparticles also have different effects on animals, from a mouse to a rat to a human. There was a study completed that silica and titanium dioxide nanoparticles are causing pregnancy complications in mice, it makes me wonder if this could be true for human as well. This stresses even more that we should not be using technology that we do not understand fully. Nanoparticles are dangerous and I believe that we should not be using them until we fully know the effects and what dangers it poses to humans as well as the environment. A study showed that “quantitative risk assessment is possible but a large knowledge gap still exists.” It was found that carbon nanotubes and nanosilver in the environment pose little risk but nanoparticulate titanium dioxide may be problematic in Swiss water bodies. The effects on natural ecosystems have not yet been fully studied either, from the nanoparticles effects on protozoan to bacteria. A study of protozoan Tetrahymena thermophilia showed that carbon nanotubes have casused the protozoa to aggregate, which impedes their ability to ingest and digest their prey bacteria species. In class we were talking about combustible dust and it makes me curious to know if these nanoparticles we are using could cause an increase to more combustible dust explosions in the future.
Additional considerations for assessing safety of engineered nanoparticles include careful selections of appropriate and relevant doses/concentrations, the likelihood of increased effects in a compromised organism, and also the benefits of possible desirable effects. An interdisciplinary team approach (e.g., toxicology, materials science, medicine, molecular biology, and bioinformatics, to name a few) is mandatory for nanotoxicology research to arrive at an appropriate risk assessment.