Other Alarms

These could include operation of special hazards equipment, building temperature supervision, supervision of city water pressure, tank level and temperature, dry pipe air pressure, supervisory pressure in preaction systems, smoke and gas detectors. 

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First-out annuneiators are highly desirable and should provide suffieient points to aeeommodate the speeified alarm and shutdown funetions. Standard features should inelude aeknowledge/silenee, lamp/test, and both audible and visible deviees for general alarm indieation. A dry auxiliary eontaet from the shutdown eireuit must be provided for expander inlet trip valve aetuation. Additional sets of eontaets are useful for other alarm requirements. 

The smaller of the two boilers became short of water first, and the low w ater level trip shut it dowm. The operator was so busy trying to get it back on line that he ignored the low water level and other alarms that were sounding on the other boiler. Unfortunately the trips on this boiler did not work, as it had been rewired (incorrectly) since it was last checked. Fifteen to 20 minutes later, someone saw flames corning out of the boiler stack. The boiler was then shut down manually. By this time most of the tubes had melted. 

Recorder reading Test sling (or other) Alarm occurred... 

To overcome hindsight bias, it is useful to examine exactly what evidence the operators had at time of each decision in the sequence of events. One way to do this is to draw the operator s process model and the values of each of the relevant variables in it. In this case, both operators thought the control valve was closed—the control room operator had closed it and the control panel indicated that it was closed, the flow meter showed no flow, and the outside operator had visually checked and there was no flow. The situation is complicated by the occurrence of other alarms that the operators had to attend to at the same time. 

The alarm system should be independent from the process control system and other alarms unless it has also been designated safety related. 

The alarms should be presented in an obvious manner, distinguishable from other alarms, and have the highest priority. 

There are a few other alarm types which are used as a part of alarm management. 

Observe The first of these sub-tasks, observing the indication, is relatively quick to do. so long as an operator is present to hear or observe the indication. Flowever, it does rely on the indication of the alarm being clear and not being hidden by other alarms or information being communicated at the same time. Any assessment of reliability of this sub-task depends on... 

If the driver that is loading or unloading at a rig site is an outside driver (employed by another company), you will need to make sure the driver is familiar with the general safety precautions on the site (the site traffic pattern, required PPE, H2S and other alarm, fire procedures, evacuation orders and alarms, etc.). You will also want to make sure your competent person watches the driver closely during the loading and unloading to make sure the driver does not put himself/herself or rig hands in danger. 

Looking at the second operator, emphasis was placed on the passing of information through oral instructions. A HEP of 0.001 was determined, based on a 15 min response time. The estimate was doubled for the 5 min response because it was felt that the second operator would be somewhat unsure if this was really happening. He also would be inundated with the other alarms sounding. For the 30 min period, the HEP reduced to 0.0005. 

Unique (not duplicating any other alarm) Timely (not long before any response is needed, or too late to do anything) Prioritized (indicating the importance that the operator deals with the problem) Understandable (having a message that is clear and easy to understand)... 

Which one of the following emergency procedures would be MOST LIKELY to be entered FIRST as the result of a POOL LEVEL alarm (no other alarms) ... 

Similarly, the Revisions to UFC Article 80 required that a continuous gas-detection system shall be provided to detect the presence of gas at or below the permissible exposure limit or ceiling limit. The detection system shall initiate a local alarm and transmit a signal to a constantly attended control station. The alarm shall be both visual and audible and shall be designed to provide warning both inside and outside of the storage area. The audible alarm shall be distinct from all other alarms. It defined a continuous gas detection system as a gas-detection system where the analytical instrument is maintained in continuous operation and sampling is performed without interruption. Analysis may be performed on a cyclical basis at a frequency not to exceed 30 minutes. P1... 

In general alarm sounders giving audible signals must be appropriate to the circumstances and must not be able to be confused with any other alarm. 

If an alarm system is to be effective, it must be used, tested, and maintained according to strict policy. Any personal alarm devices should be carried and tested as required by the manufacturer and facility policy. Maintenance on personal and other alarm systems must take place monthly. Batteries and operation of the alarm devices must be checked by a security office to ensure the function and safety of the system. Any mechanical device used for security and safety must be routinely tested for effectiveness and maintained on a scheduled basis. 

Consider a situation where there is a regular pump and a spare pump (Hollifield and Habibi, 2007). During typical operations, there could be zero, one, or two pumps running, with the latter situation occurring during a routine switch from one pump to the other. Alarms can be used to indicate the status of each pump. If the alarm strategy is to have an alarm activate when a pump is not running, one of the two pumps is always in an alarm state. 

Enhanced status control - Continuous monitoring of selected parameters RCS level, core exit and RHR system temperatures, RHR system operation - TS modified to require periodie verification of water level throughout the outage. - Installation of a permanent monitoring of the eavity and the RCS level from the control room - Enhancement of the water level instrumentation and other alarms to support operators and improve the response time to an (ineipient or actual) loss of RHR during the mid-loop operation - See also the entries under Increased availability.. ... 

Enhancement of the water level instrumentation and other alarms to support operators and improve the response time to an (incipient or actual) loss of RHR during the mid-loop operation. 

How many other alarms will there be at the same time ... 

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