RFID laundry glossary: the terms explained

About this glossary

RFID in a laundry brings together two vocabularies: the one of radio identification and the one of the laundry process. This glossary explains the terms we use on our pages, each in a few sentences, with a link to the page that goes into it further. It is sorted by topic, not alphabetically, so related terms stand together.

RFID basics

RFID

Radio-frequency identification. A reader identifies an object by radio through a tag attached to it, without line of sight. In a laundry, every textile carries a washable tag with its own ID.

Passive tag

A tag without a battery. It takes the energy it needs from the reader’s signal and answers with its ID. Laundry tags are passive, so there is no battery to run down.

UHF RFID

RFID in the ultra high frequency band, about 860 to 960 MHz depending on the region. UHF reads many tags at once over several metres, which is why it is used for laundry tags. Saphire One works from 860 to 928 MHz.

HF RFID

RFID at 13.56 MHz, the frequency of NFC. It works over shorter distances than UHF. See UHF vs. HF RFID for laundry tags.

EPC

Electronic Product Code, the identity number a UHF tag answers with. The software links that number to an item, a customer and a wearer.

Reader

The device that sends the radio signal and receives the tags’ answers. Together with its antennas it forms a read point.

Antenna

The part of a read point that sends and receives the radio signal. Its position and number decide which zone the read point covers.

Read range

The distance at which a tag can be read. Saphire One reaches up to 12 m, based on EECC free-air testing under FCC conditions; actual read range depends on reader setup, tag orientation, textile arrangement and operating environment.

Bulk reading

Reading many tags at once, for example a full cart or a closed bag in one pass. It is the main reason laundries use UHF RFID.

Proximity effect

When many tags lie very close together, as in a dense load, some of them are not read. Good tags and well-planned read points reduce it; redundancy across stations corrects the missed reads.

False negative

A tag that is there but is not read, for example because of the proximity effect. A later read at another station shows that the item was there all along.

Hardware and read points

Read point

A place in the process where tags are read: a tunnel, a portal, a read station, a cabinet or a drop box. Each read is booked to an item, a place and a time.

RFID tunnel

A read point that a cart, cage or bag passes through, reading the whole load in one pass. Cheaper and faster than a portal. See RFID tunnels, portals and read stations.

RFID portal

A read point that does the same job as a tunnel but encloses the load, which shields it and makes the read more accurate. It costs more than a tunnel.

Read station

A read point where textiles pass one by one or in small batches, typically at sorting, drying and folding.

Drop box

A fixed box at the customer site where used textiles are handed back and read.

Movable cabinet

A read cabinet on the delivery truck that records what the customer hands back.

Shielding

Measures that keep a read point from reading what it should not: the cart behind, the neighbouring line or the clean side.

Key stations

Intake, drying and folding: the three read points that cover the laundry cycle and give each item several reads per cycle.

Redundancy

Reading the same item at several stations, so a tag missed at one station is read at the next and the data corrects itself.

The laundry process

Intake

The step where soiled textiles arrive at the laundry. Anything counted at the laundry, including returns, is intake.

Sorting

The step where textiles are sorted into wash programs. Worn or damaged pieces can be flagged here.

Extraction press

The press in a tunnel washer line that squeezes water out of the load under high pressure. Saphire One is specified for 60 bar.

Flatwork ironer

The machine that dries and irons sheets and table linen between heated surfaces. The tag withstands its heat.

Quality check station

The station right after folding where pieces are checked. Pieces with a weak, defective or missing tag are re-tagged here.

Dispatch

The step where packed carts leave the laundry. The dispatch read becomes the delivery record per customer.

Wash cycle

One full pass through washing, extraction, drying and finishing. Laundry tag life is measured in wash cycles; Saphire One is designed for 200 industrial wash cycles.

Sew-in tag

A tag sewn into the textile. Saphire One sew-in: 70 × 10 mm, 1.6 mm thick.

Heat-seal tag

A tag sealed onto the textile with a heat press. Saphire One heat-seal: 72 × 12 mm, 1.6 mm thick.

Re-tagging

Replacing a defective or missing tag. The item keeps its history, because the link between tag and item lives in the software.

Rental, stock and figures

Linen rental

A service in which the laundry owns the textiles and rents them to customers, so it answers for every piece. See RFID linen tracking.

Uniform rental

Rental of workwear and uniforms linked to wearers at a customer site. See how RFID works in uniform rental programs.

Balance per customer

What a customer holds: dispatched pieces minus returned pieces, per item type. With RFID it comes from reads.

Par level

The number of sets per bed or per wearer a customer plans to have in circulation. Balances show whether the par level is really there.

Linen loss

The share of textiles that leave the cycle without being retired on purpose. See linen loss.

Loss rate

Linen loss over a fixed period as a share of pieces delivered, per customer and item type.

Wash count

How often an item has been washed. With RFID every item carries its own count.

Item history

Everything recorded about one item: customer, wearer, wash count, repairs, last seen where.

OEKO-TEX Standard 100

A certification for harmful substances in textiles. Saphire One is certified to OEKO-TEX Standard 100, product class I.