Ignition interlock

Figure 21-12. The cumulative effects of installing alcohol ignition interlocks versus a 12-months license suspension on the likelihood of NOT incurring a repeat DWI offense. The comparison group is further divided into those who received their license at the end of the suspension period and those who did not (from Marques et al, 2003, with permission from Blackwell Publishing),...

Beck, K., W. Rauch, E. Baker and A. Williams (1999). Effects of ignition interlock license... 

Beimess, D. J. and P. R. Marques (2004). Alcohol ignition interlock programs. Traffic Inj. Prev., 5, 299-308. 

Bjerre, B. (2003). An evaluation of the Swedish Ignition Interlock program. Traffic Inj. Prev.,... 

Marques, P. R. (2005). Alcohol Ignition Interlock Devices Volume II - research, policy and program status. International Council on Alcohol Drugs and Traffic Safety Report of Working Group on Alcohol Ignition Interlocks. Presented at the 6 Annual Alcohol Ignition Interlock Symposium. Annecy, France. September, 25-27. 

Federal Motor Vehicle Safety Standard Number 208 was one of the 20 initial vehicle safety standards issued in 1967. It required installation of lap and upper torso restraint belts in each front outboard seat of most cars and lap restraint belts in every other seating position. The requirement has changed several times over the last two decades. Manual seat belts were and are available in almost all cars in use but only a minority of passenger car occupants use belts. In order to increase usage for model year 1973 cars a continuous light and buzzer remained on until the front seat belts were fastened. Next, the seat belt-ignition interlock did induce an increase in safety... 

Adverse public reaction might lead to another congressional reversal as m the cases of ignition interlocks and mandatory motorcycle helmet use, and an apparently promising technological advance would be lost. 

Process or heating plant may have controls ranging from manual operation with some processes supervised by interlocks to semi-automatic and fully automatic operation. Deciding factors will include temperature of operation, frequency of ignition, degree of operator supervision, and rating of the plant. For example, boiler plant, both steam and water, will invariably have automatic control whereas tunnel kilns operated continuously at high temperature are unlikely to require it. 

The definition of an automatic burner is A burner where, when starting from the completely shut-down condition, the start-gas flame is established and the main gas safety shut-off valves are activated without manual intervention. This means that a burner is only automatic if it is ignited by means of a remote interlock (e.g. thermostat, timeswitch, etc.) closing. A burner is not automatic if it has a pilot burner that remains ignited in the off condition. Nor is a burner strictly automatic if a start button needs to be pushed, even though the controls may comply with all requirements for automatic burners. 

As previously stated, the purpose of the solvent evaporation systems is to remove the solvent from the lacquer particle without deforming the spherical shape of the particle. The loss of the liquid level in the evaporators will result in a very sensitive lacquer and could result in thermal ignition of any residue on the evaporator walls. Level controls are interlocked with the steam supply to the evaporators to prevent thermal ignition from occurring. 

At the present time, it is impossible to obtain an explosion-proof feeder. The feeder s electric coil can burn out causing sparking within the enclosure and possibly igniting powder or solvent vapors that have accumulated. To avoid this possibility, air purge systems are installed to prevent the buildup of explosive or flammable material. The air purge systems are also interlocked with the equipment so that in the event of lost air flow, the vibrator will be shut down and an alarm sounded. 

A pipe DN 80 (88.9 mm outer diameter) is equipped with a lagging of thickness of 4.1 nun. Normally steam at 150 °C passes through it. An operator mistakenly exposes the pipe to steam of 175 °C by placing a multi-port valve into a wrong position. An interlock, which would have prevented this, is not installed. The ambient temperature is 20 °C. Is self-ignition (at 181 °C) to be expected ... 

Class 4 lasers include all lasers with beam power greater than class 3B. By definition, a class 4 laser can burn the skin, in addition to potentially devastating and permanent eye damage as a result of direct or diffuse beam viewing. These lasers may ignite combustible materials and thus may represent a fire risk. Class 4 lasers must be equipped with a key switch and a safety interlock. Most entertainment, industrial, scientific, military, and medical lasers are in this category. 

Here the following problem arises. Within the area of the installation described above, water gas is handled at high temperatures. Whenever the uncooled product gas mixes with air, it will ignite and burn. Therefore, a gas leakage must be prevented at any cost. This is why valves (1) and (2) are interlocked in such a way that (2) can be opened only after (1) has reported the closed position. Likewise, valve (1) can be opened only as long as valve (2) reports the closed position. It is of the utmost importance that the above-described system is adequately protected against any undesirable gas leakage from the dust removal zone. 

Energy Radiation ionizing, electromagnetic, thermal/ nuclear, or UV Erratic behavior of electronic equipment, safety interlock, interference, human fatality, charring of organic material, decomposition, fuel ignition,... 

Energy sources Fire explosion, electrocution/ short circuiting, personal/ equipment burnt, ignition, increase in toxicity Cut off energy source quickly if possible, lockouts snd interlock functions, initiate emergency handling procedure... 

Interlocks should ensure that all vent and circulating fans are on before feed begins. Fan failure should stop feed, deactivate ignition, and close the appropriate valves. Feed must be on before safety shutoff valves are opened and before the heating system can be activated. 

Portable and transportable apparatus should be excluded from the hazardous areas, as far as possible, because the eonditions of use make it, and particularly its flexible cable, a greater ignition and accident risk than fixed apparatus. When it is used, it should be frequently inspected, tested and maintained to avoid trouble. The flexible cable should be of the screened type. The connection to the supply should be by means of an EEx plug and socket, interlocked with the supply switch, to ensure that the plug can only be inserted or withdrawn when the circuit is dead. It is also recommended that the circuit is protected by a residual current circuit breaker or circulating current earth monitoring protection or both. A sound approach is to ensure, via suitable management procedures, that such apparatus is only used in a hazardous area after the area has been proven by measurement to be gas-free - work would then usually be carried out under a permit to work issued by the process specialist who certifies that the area is gas-free. 

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