In Florida, civilian review boards face a threat to their very existence. A state representative recently filed a bill that would make it illegal for cities to create any kind of agency for receiving, processing, or investigating “complaints of misconduct by law enforcement and corrections officers.” The bill sponsor cited the stress that investigations can put on officers. It's a move reminiscent of other efforts by state officials in Florida to restrict how their local counterparts handle the justice system.

We all need to breathe the oxygen (O₂) in the air in order to live. However, oxygen is just one of the many gases present in the air. Normal ambient air contains an oxygen concentration of 20.9% v/v. When the oxygen level falls below 19.5% v/v, the air is considered oxygen-deficient. Oxygen concentrations below 16% v/v are considered unsafe for humans.

Flammable gases list

Once body camera footage is released, it can be instrumental in countering false police accounts that likely would have been accepted as true. Take the case of Ronald Greene, who was killed by state police outside of Monroe, Louisiana, in 2019. Officers reported he had died in a car crash. But body camera footage revealed that they’d beaten, tased, and mocked Greene and then left him handcuffed and shackled face down while waiting for an ambulance. Three of the officers involved are facing criminal charges, and the agency is under federal investigation.

The lowest temperature at which the surface of the liquid produces enough vapours to ignite if given an ignition source.

The technology has enjoyed broad support from both the general public and from police. After a slew of high-profile shootings seared public consciousness through the lens of bystander video, the wisdom of recording all police interactions with the public has been hard to argue against.

In confined spaces (closed or poorly ventilated environments), the concentration can sometimes be greater than the UEL. Danger can occur when the doors or hatches are opened, because the arrival of air from the outside can dilute the gases and form a dangerous combustible mixture. For this reason, perfumes are added to some gases to make them easier to detect.

Their review of 79 police killings captured by body camera footage in June 2022 found that footage has only been made public in 42% of cases.

Flammable gases and toxic gases are treated separately because they involve different risks, regulations and sensors. However, there are many gases that are both combustible and toxic, meaning that toxic gas detectors have to be approved for hazardous areas.

Non FlammableGas

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Perhaps hard-to-get footage is better than none at all, though. A recent NBC News investigation found that unlike local law enforcement, federal agents don’t generally wear cameras, essentially turning shootings by the FBI, the Bureau of Alcohol, Tobacco, Firearms, and Explosives, the Drug Enforcement Agency, and the U.S. Marshals into a black box.

An important notion is that of Occupational Exposure Limit, or OEL. The purpose of the OEL is to prevent irreversible damage to a person’s health caused by the use of one or more hazardous substances. It offers protection against adverse effects on health, but does not cover the risk of explosion. In other words, the goal is to make sure that the exposure levels in the workplace are lower than the acceptable legal limit. These limits are a valuable tool for risk evaluation and management. To obtain a representative measurement of the degree of contamination of the air inhaled, three elements are required:

It is often forgotten that oxygen enrichment can also cause a risk. At increased O₂ levels the flammability of materials and gases increases. At levels of 24% items such as clothing can spontaneously combust. Oxyacetylene welding equipment combines oxygen and acetylene gas to produce an extremely high temperature. Other areas where hazards may arise from oxygen-enriched atmospheres include manufacturing areas for storing rocket propulsion systems, products used for bleaching in the pulp and paper industry and clean water treatment facilities.

Flammablegasexample

The Chicago Civilian Office of Police Accountability is one of the few in the country with direct access to body camera footage, a power it received after outrage over the shooting death of Laquan McDonald in 2014. But that hasn’t stopped the city’s police union from trying to bargain away other avenues of public oversight. In current contract negotiations, the union is seeking a provision that would allow officers accused of misconduct to remove their cases from the docket of the public Chicago Police Board, “and instead have them decided privately by an outside third party,” the Chicago Tribune reports.

Is methane a flammablegas

Jamiles Lartey Twitter Email is a New Orleans-based staff writer for The Marshall Project. Previously, he worked as a reporter for the Guardian covering issues of criminal justice, race and policing. Jamiles was a member of the team behind the award-winning online database “The Counted,” tracking police violence in 2015 and 2016. In 2016, he was named “Michael J. Feeney Emerging Journalist of the Year” by the National Association of Black Journalists.

A recent investigation by ProPublica and The New York Times, however, found that the promise of body cameras has been undermined by policies around the release of footage. “Departments across the country have routinely delayed releasing footage, released only partial or redacted video or refused to release it at all,” write Eric Umansky and Umar Farooq. “They have frequently failed to discipline or fire officers when body cameras document abuse and have kept footage from the agencies charged with investigating police misconduct.”

Another limitation of body camera footage is that it relies on subjective interpretation. When TheGrio news network recently sent footage of the same police use-of-force incidents to 10 experts, interpretations of what they saw and heard varied dramatically, even on basic matters including whether or not the subject complied with officer demands.

Helps determine where the sensor will be located.  Gas/vapour density is relative to that of the air: if the air = 1.0 and vapour density < 1, it will rise in the air, while if vapour density > 1, it will sink in the air.

list of flammable gases - wikipedia

In the case of toxic substances, the main concern – aside from environmental issues - is the effect of these gases on employees. Inhaling, ingesting or having one of these gases penetrate your skin may be harmful even at very low concentrations. The number of deaths caused by exposure to toxic gases is higher than the number of deaths due to explosions involving flammable gases.

Police oversight agencies, such as civilian complaint review boards, benefit from the footage — when they can get a hold of it. As we covered in a prior edition of Closing Argument, these kinds of organizations are popular (many of the nation’s large cities have one), but they have dramatically different amounts of power from place to place. It’s common for their power to expand or contract as political dynamics shift in a given city or state, especially through protracted battles with police unions.

The toxicity of the gas concerned must without fail be taken into consideration. For example, a detector that only measures a weighted average or a detector that takes a sample for analysis in the laboratory does not protect employees against short-term exposure to a lethal dose of a highly toxic substance. However, it may be normal to exceed the long-term exposure limits temporarily in certain parts of the plant or facility, and it is not necessary to trigger a warning in such cases. The optimal detector is therefore one which is capable of monitoring both the long-term and short-term exposure levels as well as the instant warning levels.

In New York the civilian review board must navigate a maze of bureaucracy to obtain body camera footage, and now faces a new stumbling block. The board announced this week that it was suspending several categories of investigation into police misconduct due to budget cuts demanded by Mayor Eric Adams, a former police officer.

Flammablegaspropane

At a certain temperature, flammable gases will spontaneously ignite in a normal atmosphere without an external source of ignition such as a flame or spark. We call this temperature the autoignition temperature. The surface tempertaure of the equipment used in hazardous areas must not be higher than the autoignition temperature. The maximum surface temperature is therefore indicated on the equipment.

Over the past decade, the adoption of body-worn cameras has been one of the most popular and durable police reforms in the U.S.

The most common way of measuring the concentration of toxic gases is in parts per million (ppm) and parts per billion (ppb). For example, 1ppm is the equivalent of a room filled with a million balls, 1 of which is red: the red ball represents 1ppm. However, it is essential to measure the exposure time, not just the concentration of gas, because the harmful effects are often caused by regular exposure over a long period of time.

In New Jersey, by contrast, lawmakers advanced a bill this week that would give civilian complaint review boards the power to subpoena witnesses — an authority that these boards and their supporters often covet. A proposed amendment would only apply the power to four of the state’s largest departments as a pilot program for five years, making the bill bittersweet for advocates of more oversight. “Examples of police misconduct and brutality exist in literally every corner of New Jersey,” said Joe Johnson of the American Civil Liberties Union of New Jersey, according to the New Jersey Monitor. “So civilian oversight is important everywhere.”

Most flammablegaslist

Flammable and inflammable gases

Victims of police violence and their families often seek the release of body camera footage, in the hope that public outrage will lead to accountability that is otherwise elusive. This week, the mother of an 11-year-old Black boy shot by police in Mississippi made exactly that demand after a grand jury declined to press charges. “I feel disgusted, outraged and emotionally damaged,” she said at a Wednesday press conference, after viewing the footage in private.

The flammability or explosive limits of a gas refer to the minimum and maximum concentrations of the gas necessary to support its combustion in the air (burning or explosion):

By definition, a gas is a swarm of molecules that move randomly and chaotically, bumping into each other and with whatever else happens to be in their way. Gases fill all the space available and, because they move so quickly, they soon mix with everything else in the atmosphere in which they find themselves. Gases may be heavier, lighter or of the same density as air. Some gases have a smell, while others are odourless. They may be coloured. Just because you can’t see, smell or touch a gas doesn’t mean it is not there. The word gas comes from the Greek “chaos” which refers in mythology to the chasm, void or empty space that existed before life began. The word was coined in the 17th century by the Dutch chemist Jean-Baptiste Van Helmont to describe the notion of emptiness.

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Hydrocarbon compounds such as acetylene, ammonia, hydrogen, propane, propylene and methane are all flammable gases. They are also known as combustible gases. Combustion is a chemical reaction in which oxygen mixes quickly with another substance, resulting in the release of energy, in the form of heat or even flames.

If the concentration is lower than the LEL, we say that the gas/air mixture is too lean to burn, because there is not enough gas to produce an explosion. The risk of fire increases in proportion to the percentage of flammable gas present. Above the UEL, the mixture lacks oxygen. The air becomes too rich to burn, and the risk of a fire starting decreases. Generally speaking, increasing the pressure, temperature or concentration increases the flammability range.

Exposure times are calculated based on eight-hour periods (8-hour OEL) and 15-minute periods (STEL). For certain substances, even a very short exposure can be so serious that they only have a short-term exposure limit, which should never be exceeded, even for a few seconds. The cancerogenic nature, the toxic effects on reproduction, irritation and degree of sensitivity are taken into consideration when putting together a proposal for an OEL based on current scientific knowledge.

In normal operating conditions, industrial facilities do not have gas leaks or, at most, they will contain a few traces of gas. Gas detectors do the job of monitoring the risks before combustion, in other words, they measure the concentration of gas present between 0% and the Lower Explosive Limit (LEL). If the lower limit is reached, shut-off or site evacuation procedures are triggered. In practice, these measures are usually taken when the concentration level is less than 50% of the LEL, to guarantee a sufficient safety margin.

The air we breathe contains oxygen and nitrogen, natural gas or methane is used in many homes for heating and cooking... Gas is part of our everyday environment but if we are not careful, it can quickly become dangerous.

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