NYSDOT CPM scheduling requirements: Item 639 Type 2
The New York State Department of Transportation states its critical path method requirement as a special specification item incorporated into the contract: Item 639.2X010011, "CPM (Critical Path Method) Progress Schedule — Type 2", dated 15 August 2014, 30 pages. Because it is an item of the contract, it outranks any general standard it conflicts with on a project that carries it.
A second NYSDOT document sits beside it: the agency's Best Practices for CPM Schedule Specification Compliance manual, 9 May 2016. It restates Item 639's rejection criteria and names, for each, the numbered P6 filter a reviewer applies — then lists all twenty-nine filters. It says of itself that it is guidance and not official policy, and that it does not replace the Item 639 specification. That distinction is load-bearing here: guidance does not breach. Where only the manual states a predicate, this project reports an observation rather than a failure, and says which document it rested on.
Section numbers, thresholds and filter identifiers below are stated in this project's own words with the citation attached. The manual asserts no copyright notice, which is a finding and not a permission; a New York State agency document is not a federal work.
What Item 639 requires
| Requirement | What Item 639 Type 2 states | Clause |
|---|---|---|
| Scheduling software | Oracle-Primavera P6, named — and hosted on the Department's own servers, with contractors working in NYSDOT's environment through Department-issued accounts. | Item 639, software provisions |
| Baseline schedule | Due at award. Beyond mobilisation, procurement and erosion control, work may not start until the baseline has been submitted and is free of the paragraph I.1 immediate-rejection deficiencies. The Engineer comments on an optional draft baseline within 5 Work Days. | Item 639 paragraph I.1 and the baseline provisions |
| Update frequency | Monthly progress schedules, plus a weekly status report. | Item 639 |
| Narrative | Required. | Item 639 |
| Recovery schedule | A defined term in this specification, unlike several of the other agencies on this site. | Item 639 |
| Time impact analysis | A defined term in this specification. | Item 639 |
| Float ownership | Total float is defined as an attribute of a network path, not of an individual activity. Item 639 expressly names float suppression — zero-free-float constraints, padded durations, over-restrictive calendars — as preventing true sharing of total float between the Department and the Contractor. | Item 639 |
| Activity durations | Not more than 15 work days, excepting submittal and procurement activities, unless the Engineer permits otherwise. | Item 639 F.1(h) |
| Lags | Lag may not exceed 10 days, and negative lag is prohibited. | Item 639 F.1(i) |
| Milestone calendar | Milestone activities take the standard Global calendar the clause names in full — a 365 day / 8 hour Milestone/Curing calendar. | Item 639 F.1(g) |
Nine deficiencies that end the review before it starts
Paragraph I.1 lists nine deficiencies that are grounds for immediate rejection by the Engineer in Charge, without further review, analysis or comment. Four of them are decidable from the schedule file alone:
- Open ends. An activity with no predecessor, or none with no successor, excepting the schedule's first and last activity — and the clause is written on the singular, so a second dangling start is a deficiency (I.1(c)).
- Unauthorized constraints. Any activity constraint the EIC has not authorized in writing and the specification does not itself allow (I.1(d)). A schedule carrying no constraint has nothing to authorize, so it decides cleanly with no correspondence supplied.
- Actual dates past the data date. Strictly after, and the specification and the manual's filter agree on the inequality, so an actual date falling exactly on the data date is permitted and is not reported at all (I.1(e)).
- No continuous critical path. The schedule must show one unbroken critical path running from the data date through to the final activity, identified by the Longest Path method (I.1(g)). Longest path, not zero total float — the two are not interchangeable, and the specification's own definitions settle which one it means.
Three more are facts about the submission rather than the schedule: failure to schedule as of the data date, failure to attach the Scheduling/Leveling Report, and failure to attach the narrative and appendices. A schedule file records none of them, and this project does not report on them.
The Department-hosted P6 environment
Of the five agencies described on this site, NYSDOT's software requirement is the strongest. Other agencies name P6 and a file format. NYSDOT names Oracle- Primavera P6 and hosts it: the schedules live on Department servers and the Contractor works there under an account the Department issues. That changes what "submission" means — the schedule is not only delivered to the agency, it is built inside the agency's environment — and it explains why the Best Practices manual is organised around global P6 filters a reviewer runs against that database rather than around documents a reviewer receives.
Float suppression, named as such
Most specifications on this site say float is shared and stop there. Item 639 goes further and names the mechanisms by which a schedule can appear to share float while not doing so: constraints that drive free float to zero, durations padded beyond the work they represent, and calendars restrictive enough to absorb time that would otherwise show as float. The clause's stated purpose is true sharing of total float between the Department and the Contractor.
Two of those three mechanisms leave marks a file carries — constraints and calendars — and the third, padding, does not, because a duration does not record what it was intended to absorb. This project reports what the imported schedule contains and cites the clause; it does not conclude that any particular duration was padded.
Where Item 639 differs from the manual, and it is not cosmetic
- The 15-day exception. Item 639 F.1(h) excepts submittal and procurement activities from the duration limit. The manual's filter 05d describes submittals, fabrication and inspection activities as excluded. Fabrication and inspection are in the guidance and not in the contract term. This project follows the contract, names both readings when it abstains, and asks for the excluded activities by identifier — because neither exception is decidable from a schedule file either way.
- Milestone relationships. The manual's filters check two constraints on milestone logic. Item 639 F.1(i) states four. The contract's four are what this project checks.
What this page does not tell you
- It does not tell you which clauses govern your project. Item 639 comes in more than one type, and the type that appears in a given contract is a fact about that contract's incorporated documents, not about the agency. Read the item as incorporated, with any addenda.
- Several requirements above rest on Item 639 as summarised here, not on a clause-by-clause reading of all 30 pages. Where a row says a term is "defined", that is what was established: the specification defines it. The operative day counts and procedures for recovery schedules and time impact analyses were not established here.
- Twelve of the manual's twenty-nine filters key on P6 activity codes — responsible party and type of work — which this engine's schedule model does not carry, and three are keyword filters whose keywords the manual does not print. Those are not checked, and inventing the keywords would attribute this project's guess to the agency.
- This project computes and reports; it does not decide submissions. It states what the imported schedule contains and checks it against the clauses cited. Excusability, entitlement and the adequacy of a schedule are not questions it answers. The reviewing authority determines acceptance.
Related pages
- How state DOT scheduling specifications compare.
- UFGS scheduling requirements.
- Glossary — total float, longest path, data date, free float.
- What the engine does and limitations.
- The conformance rule catalogue and the standards map §2.6, which records how these two documents were read and which filters were refused.
Source: web/pages/nysdot-scheduling.md. Source commit date: 2026-09-11.