following periodic inspection and testing of the fixed electrical systems, the company who performed the test have identified in the corrective / remedial work that further testing is required on the PI / and SI? does anyone knows what this is and whether this should have been tested as part of the initial inspection and testing? thank you

AM1, Please explain a little more. The Periodic Inspection report will be limited to that agreed between the client and contractor. For example it is acceptable to only inspect & test 10% of 13A socket outlets. However, if defects are found then this frequency must be increased. However, if it has been agreed between client & contractor that no increases in inspection, thus cost will be made, then it would be acceptable to put down a code 3, further investigations required. Has the PIR been given an acceptable or unacceptable result? What do you meen by SI?