When a signage delivery goes wrong, the cause is usually upstream of the supplier. The tender asked for "ISO-compliant safety signs, durable quality, suitable for industrial use" — three phrases that cannot be measured, and therefore cannot be failed. Everyone involved acted in good faith and the result still had to be re-ordered.
A specification is checkable when every requirement in it can be answered with a number, a code or a named document. The nine points below are what that looks like in practice.
1. Name the standard with its edition year
"ISO 7010" leaves the revision open, and revisions change symbols. Write ISO 7010:2019. The same applies to every other reference in the document: the year is part of the requirement, not decoration.
2. Identify specific signs by reference code
ISO 7010 gives each registered sign a reference code. A description like "emergency exit, arrow left" can be satisfied by several signs; a code cannot. Where you mean a family rather than one sign, say that explicitly.
3. Describe the environment, not the material
This is the single highest-value change to most tenders. Specifying "aluminium" or "polyester film" fixes the answer before the question has been asked, and it transfers the engineering judgement to whoever wrote the tender. Describe the exposure instead:
- indoor or outdoor, and whether under direct sunlight
- temperature range in service, with units
- cleaning regime — pressure washing, solvents, disinfectants, frequency
- chemical exposure, named where known
- salt or humidity
- mechanical abrasion, foot or vehicle traffic
- substrate the marking must adhere to, and its condition
Then let the supplier propose a substrate and document why it meets that exposure. You get an engineered answer and an audit trail, instead of a material name and a hope.
4. Require figures with their test conditions
A performance value without its measurement condition is marketing. "High luminance" means nothing; a luminance stated in mcd/m² after a defined excitation and decay time, measured to a named standard, is a specification. Ask for each figure in the form *value + unit + test condition + standard*, and state that figures without conditions will be treated as not offered.
5. Ask for the document package as a deliverable
Documentation supplied "on request" tends to arrive after the invoice, when nobody needs it any more. Make the datasheets a line item due with delivery, and say which categories they must cover. The reason is practical rather than bureaucratic: at the next audit, the evidence that your marking matches your risk assessment is that pair of documents sitting together.
6. Separate the product from the installation
Three responsibilities are routinely bundled into one sentence and then contested:
| Responsibility | Who typically owns it |
|---|---|
| The sign is the correct sign | Specification and supply |
| The sign is in the correct place | Site — from the layout and risk assessment |
| The sign is fixed so it stays there | Installation |
Name the owner of each in the tender. A correct sign in the wrong place is a finding, and it is nobody's fault by default.
7. State the language, per site
Signage language is a site decision with legal consequences, and it is not always the language of the head office. Marine marking is English by default. Multi-language sites need the combination stated, not left to the supplier — and text length changes the layout, so this affects the sign size as well.
8. Give dimensions with units, and a quantity per format
A sign schedule that lists formats and counts can be picked and checked. One that says "assorted sizes as required" cannot be quoted accurately, which means the price you compare between suppliers is not comparing the same thing.
9. Say what happens in five years
Marking has a service life, and replacement is cheaper to plan than to discover. Ask how the product's service life is evidenced, what the expected replacement interval is in the exposure you described, and whether the same article will still be available. A durable sign that has been discontinued is a re-survey.
A note on what a tender cannot outsource
No supplier can tell you which signs your site needs. That comes from your own risk assessment and layout, and it stays with you. What a supplier can do is make sure the sign you specified is the registered sign it claims to be, that its substrate suits the environment you described, and that both statements come with documentation you can put in front of an auditor.
Setting the tender up so those three things are checkable is the whole job.
Documentation before ordering
Every DENFOIL product line states which standards it is designed to meet, with the supporting figures in the product documentation rather than in this article. Request a document package , or find your distributor in Denmark, Norway, Sweden or the Netherlands to review a draft specification before it goes out.