What Is ITP? Inspection and Test Plan

Quick Answer

An Inspection and Test Plan (ITP) is a document that lists every inspection, examination, and test activity required during manufacturing, fabrication, or construction of piping materials and equipment. For each activity, the ITP specifies the applicable standard, acceptance criteria, responsible party, and the level of involvement by the buyer and third-party inspector (TPI)—classified as Hold (H), Witness (W), Monitor (M), or Review (R) points. The ITP is the central quality control document linking mill test certificates, NDT reports, hydrostatic tests, and dimensional checks into a single traceable package.

ITP Structure

A typical ITP is organized as a matrix with the following columns:

Column	Content
Item number	Sequential activity reference
Activity/operation	Manufacturing or inspection step (e.g., “Chemical analysis,” “UT of weld,” “Hydrostatic test”)
Reference standard	Applicable code/specification (ASTM E8, ASME V Art. 4, ASME B31.3)
Acceptance criteria	Pass/fail limits (e.g., “Min UTS 415 MPa,” “No cracks per ASME B31.3 Table 341.3.2”)
Manufacturer (M)	Manufacturer\u0027s QC involvement (always performs)
Buyer/client (C)	Buyer or EPC contractor involvement level: H/W/M/R
Third-party inspector (TPI)	Independent inspector involvement level: H/W/M/R
Records/documents	Deliverable (MTC, NDT report, test chart, dimensional report)

Involvement Levels

Code	Level	Meaning
H	Hold point	Production stops until the inspector witnesses and approves; cannot proceed without sign-off
W	Witness point	Inspector is invited to witness; production may proceed if inspector does not attend after notification
M	Monitor	Inspector may attend and observe at any time during the activity
R	Review	Inspector reviews documentation/records only (no physical attendance)

Hold points are reserved for critical activities: final hydrostatic test, material identification, final dimensional inspection, and certificate review. Excessive hold points delay production; too few compromise quality oversight.

Sample ITP: Seamless Carbon Steel Pipe (ASTM A106 Gr. B)

#	Activity	Standard	M	C	TPI	Record
1	Raw material verification	ASTM A106	X	R	R	Heat certificates
2	Chemical analysis (ladle + product)	ASTM A751	X	R	R	Chemical test report
3	Pipe manufacturing (piercing, rolling)	ASTM A106	X	M	M	-
4	Heat treatment (normalizing)	ASTM A106	X	W	W	HT chart
5	Tensile testing	ASTM E8	X	W	W	Mechanical test report
6	Impact testing (if specified)	ASTM E23	X	W	W	CVN test report
7	Hardness testing	ASTM E10/E18	X	R	W	Hardness report
8	Flattening/bend test	ASTM A106	X	W	M	Test report
9	Hydrostatic test	ASTM A106 / ASME B31.3	X	H	H	Hydro test chart
10	Ultrasonic testing (if specified)	ASTM E213	X	W	W	UT report
11	Dimensional inspection	ASME B36.10	X	W	W	Dimensional report
12	Visual inspection (surface condition)	ASTM A106	X	W	M	VT report
13	Marking and color coding	ASTM A106 / ASME A13.1	X	W	M	Photographs
14	Mill test certificate review	EN 10204 3.1/3.2	X	H	H	MTC package
15	Packing and loading	PO requirements	X	W	M	Packing list

ITP for Piping Fabrication (Spool Fabrication)

#	Activity	Standard	M	C	TPI
1	Material receiving inspection	PO / MTC	X	W	R
2	Fit-up and VT before welding	WPS, ASME B31.3	X	W	W
3	Welding (root, fill, cap)	WPS per ASME IX	X	M	M
4	Visual testing after welding	ASME B31.3	X	W	W
5	NDT (RT/UT/MT/PT)	ASME V, ASME B31.3	X	W	W
6	PWHT (if required)	ASME B31.3	X	H	H
7	Hardness after PWHT	ASTM E18	X	W	W
8	Hydrostatic test	ASME B31.3	X	H	H
9	Final dimensional check	Isometric drawing	X	W	W
10	Documentation review and release	Project spec	X	H	H

Who Prepares the ITP?

The manufacturer or fabricator prepares the ITP based on the purchase order, project specification, and applicable codes. The buyer (or EPC contractor) reviews and approves the ITP before manufacturing begins. The TPI (SGS, Bureau Veritas, Lloyd\u0027s, DNV, TUV) uses the approved ITP to schedule inspection activities.

Common Mistake

Approving the ITP after manufacturing has started. Late ITP approval means the first hold and witness points are missed, and the manufacturer proceeds without oversight. Issue the ITP for review with the purchase order and require approval before first production. Build ITP approval lead time into the procurement schedule—typically 2-3 weeks.

The completed ITP with all signed inspection records forms the material/fabrication data book, delivered with the shipping documents and archived for the life of the asset.

Read the full guide to non-destructive testing