Saurabh N.

Float is a time (Float time) is also referred as slack time that indicates particular tasks that can be delayed without delaying the project deadlines. In float time, scheduling of task becomes more flexible which can be used to offset many risks, if planned properly. Float time is typically presented with no. of days, weeks or month that gives project lead a flexibility on how long a task can wait before proceeding with the subsequent task. In order to make most out of float time, it is crucial for project lead to identify and strategically plan the activities.
Identification of float time improves the productivity of projects as every Project is unique and may involve many complex sequences of tasks, some of these tasks are critical tasks, which means that project lead has to make sure that these tasks are completed in defined timeline.
However, some of the tasks are non-critical tasks which can be done in less time & these tasks do not have any impact on subsequent tasks, the difference in Critical task time and non-critical task time is referred as float time.
 
Below is simple Example of float in CPM: -
 
Activity
Activity Time
Intermediate Predecessor
Start
0
-
A
4
Start
B
6
A
C
6
A
D
5
B
E
7
C, D
End
0
E
 
 
 
 
With reference to above diagram and calculation, it’s important to Identify critical and non-critical activities. Critical activities must be completed within specified timelines to prevent project delays while non-critical activities have some flexibility and by distinguishing between these two, project lead can focus on utilizing float time for non-critical activities without compromising project deadlines.  
Utilization of float time can be determined to understand the potential impact on the project, resources required for meeting timeline of other critical tasks, Engaging resources in Improvement project like process improvement, professional skill development or Innovation activities etc.

The actual requirement of the FMEA is to create a very useful document used for making strategic decisions based on risk involved in process.
FMEA can be characterized in the relative risk contribution of potential failure areas associated with the process in terms of a risk priority number (RPN). This RPN can be obtained as a product of three phase of framework representing below.
 
·       Severity of Occurrence
·       Frequency of Occurrence
·       Chance of Detection
 
RPN Scales usually range from 1 to 10, with the higher number representing the higher seriousness or risk. considering ten-point Occurrence scale, 10 indicates that the failure is very likely to be occurred and is worst compared to 1 which indicates that the failure is very rare to be occurred.
 
Severity- Which indicates that the occurrence of severity of the potential effect of the failure is high when rated as 10 and low when rated as 1. Occurrence- Which indicates that the frequency of occurrence of the potential effect of the failure is high when rated as 10 and low when rated as 1. Detection - Which indicates that the chance of detection of the potential effect of the failure is high when rated as 10 and low when rated as 1.  
For each potential cause, the individual factors occurrence (O), severity (S), and detection (D)are rated and multiplied together.
 
PRN= Severity (S) X Occurrence (O) X Detection(D)
 
In order to improve the rating of PRN suitable actions cab be taken and risk can be reduced
However, the specific rating criteria for the ranking of occurrence (O), severity (S), and detection (D) are defined by the individual organization based on process and priorities.
 
·       Reduce the severity.
·       Reduce the probability.
·       Improve the design to improve the control over detection
 
Example:- Potential failure areas with risk priority number (RPN) improvement in bottling plant.
 
Sr No
Process
Potential Failure mode
Potential effect of Failure
Severity (S)
Potential Cause/ Mechanism of Failure
Occurrence (O)
Current Process control
Detection (D)
Risk Priority No
 (S*O*D)
1
Bottling plant
Less quantity
Customer complain
5
Filler
2
Weight gauge
3
30
2
Bottling plant
Insufficient seal
Mixing with other substance
3
Heat Sealer
5
Seal Test
4
60
3
Bottling plant
Wrong marking
Expiry period
1
 Manual Labeler
5
Random In Process check
3
15
 
 
For above example below Corrective Actions can be implemented such as:  
Installing automatic labeler can help improving mechanism by removing potential cause for frequency of occurrence. Installing sensor based continuous automatic Checking system to reduce chance of detection.  
 
Sr No
Process
Potential Failure mode
Potential effect of Failure
Severity
Potential Cause/ Mechanism of Failure
Occurrence
Current Process control
Detection
Risk Priority No
1
Bottling plant
Less quantity
Customer complain
5
Filler
2
Weight gauge
3
30
2
Bottling plant
Insufficient seal
Mixing with other substance
3
Heat Sealer
5
Seal Test
4
60
3
Bottling plant
Wrong marking
Expiry period
1
Automatic Labeler
1
Continuous Sensor based Automatic Checking
1
1