曝光台 注意防骗
网曝天猫店富美金盛家居专营店坑蒙拐骗欺诈消费者
and eliminated so that it is no longer a threat. For example,
if there is a tall tree obstructing takeoff and landing
traffic on a runway, the engineering solution would
be to cut down the tree. The tree (hazard) is eliminated
and normal operations can continue.
If a hazard cannot be eliminated, then you should control
or guard the hazard. The Control / Guard Solution
leaves the hazard in the system, but guards are put up or
procedures are changed in order to decrease exposure.
In the case of the tree obstructing the runway, if the tree
cannot be cut down (eliminated), then choosing to replace
the runway threshold would control or guard the
hazard. This solution is not the most effective, but the
hazard will be reduced in the operation.
If it is impossible to eliminate or control the hazard,
then warnings to personnel should be issued. This type
of solution is known as the Personnel Warning Solution.
If the tree in our example cannot be cut down, nor
can the runway threshold be moved, then warnings such
as safety alerts or Notices to Airmen (NOTAMs) should
be issued. From this, personnel who are involved in the
situation will be informed of the hazard.
The final solution that is used to assess hazards is
through the development of training or procedures.
This solution, unfortunately, is used the most in the
safety industry. The cost of eliminating or controlling
the hazard, legal issues, or conflicting company policies
may cause safety experts to choose this solution. From
this solution, procedures and training for the hazard are
applied to reduce risks of catastrophic, hazardous, major,
or critical severity. Back to the tree obstruction
example, if the tree cannot be cut down, the runway
threshold cannot be moved, nor can warnings be issued
to reduce the severity of the hazard, procedures and
training of pilots to commit a short-field takeoff in order
to rotate their aircraft early enough to clear the tree
is an example of this final type of hazard solution.
System safety also involves risk assessment and risk
acceptance. Risks are analyzed by quantifying them
according to probability of an accident, level of exposure,
and severity of the risk. Risks are ranked in numbers
from 1 through 8. An unacceptable risk is ranked
with the numbers 1,2, and 3. An undesirable risk is
ranked with the number 4. An acceptable risk is ranked
with the number 5, 6, 7, and 8, but rankings of 5 and 6
must be closely monitored. If a risk is determined to be
acceptable, then the system may continue with the operation
as normal. If a risk is determined to be unacceptable,
then operations must be discontinued immediately.
The key to risk acceptance is to manage the hazard
(risk) to a point where it is acceptable. Risks are
accepted when 1.) the risk involved is really acceptable,
but safety experts don’t like having to accept them due
to other constraints, or 2.) safety experts choose not to
take any action to eliminate or reduce a hazard.
In system safety, there is ALWAYS some amount of
risk involved. Some risks can be engineered out of the
system, other risks can be controlled or reduced, but it
is impossible to eliminate all risks. One of the major
problems in safety is that an accident usually must occur
in order to prove that a problem exists. This concept
is known as blood priority, which states that it is
easier to get a hazard corrected if a fatal accident has
just occurred. Examples of the blood priority issue can
be seen from accidents such as TWA Flight 800, the
Grand Canyon mid-air collision, and the September 11,
2001 accidents. Hazards must be identified in order to
decrease or eliminate risk in a system and it requires the
teamwork of all employees or individuals interacting in
Safety Order of Precedence
Description Priority Definition
Design for Minimum
Risk
(Engineering Solution)
1 Hazard is corrected
and eliminated
Control / Guard Solution
2 Guards put up to
decrease exposure
Personnel Warning
Solution
3 Warn personnel if
you can’t eliminate /
control the hazard
Develop Procedures
and Training
4 Develop procedures /
training to reduce risk
(Used most in safety)
Risks must be assessed in order to determine
whether they are acceptable or unacceptable.
a system in order for the process to be effective.
Is Safety First?
The DECIDE Model
• Detect a change has occurred.
• Estimate the need to counter the risk.
• Choose a desirable outcome.
• Identify actions leading to success.
中国航空网 www.aero.cn
航空翻译 www.aviation.cn
本文链接地址：
航空资料3(37)
