Task Frequency Optimization

DOE-STD-1052-93

9.1.1.1

The "as-found" condition of equipment is recorded as a "score"

from 1 to 9 (1-lowest, 9-highest) during routine PM activities.

This score is determined by the supervisor or in conjunction with

the craftsperson who performed the job.

The minimum score of "1" for a PM task means that the

condition of the component is very close to failure. A maximum

score of "9" indicates that the component is in excellent

condition.

9.1.1.2

The overall general condition of the component is not evaluated.

Only the condition with regard to the specific work performed

by the PM is used in determining the "score." For example, the

description on a maintenance job request is "Valve Packing

Change-out." The score is determined by evaluating the

condition of the packing and whether it is close to failure or in

very good condition. The score is always related to a specific

component and should only be assigned while performing work

under a PM maintenance job request. For example, if a

mechanic found that the valve packing was already leaking

before performing the PM task, then no score should be

assigned.

9.1.1.3

When performing a PM, a failure not related to the task and not

previously discovered may be uncovered. In this case, the

minimum score of "1" should be assigned and corrective

maintenance initiated to repair the component.

9.1.1.4

This method facilitates initiation of an evaluation to determine

if adjustments to PM task frequencies are warranted. The

following are typical criteria that may be used to initiate a

review of past PM performance to establish the basis to adjust

the interval of the task:

At least two consecutive high scores, as established by the

plant, may indicate the need to increase the interval

between PM task performances provided that no

corrective maintenance was performed between the two

periods.

A low score, as established by the plant, may indicate the

need to decrease the interval between PM tasks

performances.

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