DOS1 (day of supply)

DOS1 is a NATO logistics abbreviation that stands for day of supply. In NATO terminology it means a unit of supply sufficient to meet a specified requirement for one day. The NATO Glossary of NATO Acronyms and Abbreviations lists the entry as "DOS1, day of supply" and gives the French equivalent as "jour d'approvisionnement."

The term belongs to military supply planning, operational sustainment and stockholding. It gives planners a common measure for supplies. A stock is described by the number of days it can support a stated requirement, not only by its raw quantity. The plural form, DOS, covers "days of supply" and refers to the number of days for which supplies are held or planned.

How the NATO glossary defines DOS1

The glossary entry is short, and each part of it is useful to a reader who meets the abbreviation in a document.

• Expansion: DOS1 means day of supply.
• Meaning: a unit of supply sufficient to meet a specified requirement for one day.
• French equivalent: jour d'approvisionnement.
• Terminology source: the glossary attributes the entry to NATO terminology source CP 3A0029.

The numeral in DOS1 matches the single day that the unit represents. A requirement stated in multiple days is expressed as DOS.

DOS and the sustainability statement in NATO planning

NATO's Logistics Handbook uses the abbreviation DOS for "Days of Supply." The handbook states that a sustainability statement includes the Days of Supply to be held in theatre.

The same passage says the planned days of supply should cover two periods: the initial phase of a mission and the expected sustainment period. In practice, the number of days held in theatre is a planning decision tied to how long an operation is expected to run and how it will be resupplied. DOS1 is the building block, one day of supply, and DOS is the count of those days that planners commit to holding.

Checking the term in NATO's terminology resources

NATO maintains NATOTerm, its official terminology database. It contains non-classified military terminology and is maintained by the NATO Terminology Office. The abbreviation glossary cited above is the document that lists DOS1 together with its source reference, and it is the place to confirm the entry. NATO also publishes official texts and resources for readers who need the wider body of alliance documents.

What DOS1 means for a supplier bidding on Canadian public contracts

Federal opportunities are published through CanadaBuys, which carries tender notices, award notices, contract history, standing offers and supply arrangements. The CanadaBuys procurement and contracting data page describes that information.

If DOS1 or DOS appears in a requirement or a NATO-related supply document, read it as one day of supply or a stated number of days of supply. Then check how the solicitation defines the underlying requirement, since a day of supply is only meaningful against a specified requirement. Bid teams should size quantities, delivery schedules and stockholding proposals against the number of days the document asks for. Where the number of days or the requirement is unclear, put the question to the contracting authority before the questions period closes.