Designing a TB laboratory storage map with expiration control zones

A clear storage map helps a tuberculosis laboratory protect reagent quality, reduce waste and find critical materials quickly. It turns shelves, refrigerators, freezers and quarantine areas into a controlled system that staff can understand during routine work, stocktake, handover and an external assessment.

For Australian laboratories, the map must work across very different settings. A high-volume service in Sydney or Melbourne may have automated inventory systems and frequent deliveries, while a regional or remote facility in Western Australia, Queensland or the Northern Territory may need larger safety stocks, carefully planned cold-chain transport and protection against delayed freight or power interruptions.

Define the storage map’s purpose

Start by identifying every product that influences TB testing, culture, identification, antimicrobial susceptibility testing or quality control. This may include prepared and dehydrated media, supplements, stains, control strains, molecular assay reagents, extraction materials, calibrators and disposable items with storage requirements. Include opened containers, in-use working stocks and materials held temporarily for testing.

The map should show the physical location and the storage condition, rather than serving as a simple inventory list. Record room-temperature cupboards, controlled ambient areas, refrigerators, freezers, flammable-storage cabinets where relevant, quarantine shelves and waste or disposal points. Give each location a unique code, such as “R2-S3-B,” meaning refrigerator two, shelf three, bin B. The same code should appear on the inventory record and any electronic stock system.

A useful map also identifies access restrictions. Some items may require authorised staff, restricted access or additional safety controls under local work health and safety arrangements. Australian laboratories should align the system with their applicable state or territory WHS legislation, laboratory procedures, and NATA assessment expectations where accreditation applies.

Divide the laboratory into clear control zones

Use zones based on risk, temperature, status and expiry rather than arranging products only by supplier or brand. A practical layout may include an approved stock zone, an in-use zone, a quarantine zone, an expired or rejected zone, and a return or investigation zone. These areas should be physically separated or marked with unmistakable labels.

The approved stock zone holds material that has passed receipt checks and is available for use. The in-use zone contains opened bottles or prepared media with a shorter post-opening or post-preparation life. Quarantine is for deliveries awaiting inspection, products with damaged packaging, items affected by a temperature excursion and materials under investigation. Expired and rejected materials must be clearly segregated so they cannot be selected accidentally.

Apply a first-expiry, first-out system. This is safer than relying solely on first-in, first-out because two products received on different dates may have very different expiry dates. Place the earliest expiry at the front or in the most accessible position, then verify the arrangement during routine stock checks. A simple colour system can help, provided it is supported by words and dates for staff who cannot distinguish colours easily.

Match locations to product requirements

The map should show the required storage range for each category, such as controlled room temperature, 2–8°C refrigeration or frozen storage. Follow the manufacturer’s instructions and validated local procedures. Do not store products in a door shelf when temperature stability is better in the main compartment, and do not place materials against refrigerator walls where freezing could occur.

Temperature monitoring needs to support the map. Each refrigerator, freezer and controlled storage area should have an identified monitoring device, a defined acceptable range, an alarm response and a documented action for excursions. In Australia, summer heat can place extra pressure on air conditioning and cold-chain deliveries, particularly in inland areas. Remote services should consider contingency capacity, validated cool boxes, backup power arrangements and realistic delivery lead times.

The storage plan should account for the local supply chain. Specialist TB reagents may arrive through national distributors rather than local suppliers, and deliveries to Darwin, Cairns, regional Queensland or remote Western Australia can take longer than deliveries to capital cities. Record minimum and maximum stock levels using consumption data, lead time, shelf life and the consequences of a stockout. Avoid excessive ordering when products have short usable lives.

Build expiration control into the map

Every received item should be labelled or recorded with its product name, lot number, expiry date, receipt date and assigned location. If a manufacturer gives a post-opening, post-reconstitution or post-preparation limit, record that date separately from the printed expiry. Prepared media should carry preparation date, preparer identification, storage condition and discard date according to the laboratory’s validated procedure.

Create visible control points at the edge of each storage zone. For example, a shelf label can state “check monthly,” while a stock card or electronic record flags items expiring within 30, 60 or 90 days. The alert period should reflect procurement lead times and product risk. A product that takes ten weeks to replace needs an earlier warning than a commonly available consumable.

A monthly review should reconcile the physical stock with the inventory record. Staff can scan each location from left to right, check labels, remove expired material and move short-dated products forward. Document discrepancies, unexplained losses, damaged packaging and repeated overstocking as nonconformities or improvement opportunities. The GLI Quality Tool’s guidance on a monthly nonconformity report can help laboratories connect these findings to corrective action.

Make the map usable during real work

Place a simplified floor or cabinet map near the laboratory entrance, stockroom and relevant work areas. A more detailed controlled version can sit in the quality management system. Each version should show its document number, revision date, owner and approval status. When a refrigerator, cabinet or shelf changes, update the map before moving stock, then communicate the change at a team briefing.

Use plain language and consistent abbreviations. A person covering a shift, joining from another department or working after hours should be able to locate a reagent without relying on informal knowledge. This matters in Australian services where staff may rotate between metropolitan hospitals, regional laboratories and public health reference functions.

The map should support safe handling as well as retrieval. Keep incompatible chemicals separated, leave ventilation and access clear, avoid overloading refrigerators, and store heavy containers below shoulder height where practical. Do not place specimens, clean media and waste in ways that create cross-contamination risks. If a product requires security, light protection or special handling, show that requirement directly on the location record.

Digital records can add barcode scanning, automatic expiry alerts and temperature links, but technology should not become a single point of failure. Keep a controlled offline copy or printed emergency map for network outages, power failures and disaster recovery situations. The downloadable resources from the GLI Quality Tool can support the development of practical forms and controlled records.

Verify, review and improve the system

Before introducing the map, test it with the people who receive deliveries, prepare media, perform testing and manage waste. Ask staff to locate a routine reagent, a short-dated item, a quarantined shipment and a product requiring freezer storage. Observe whether they interpret the labels correctly and whether the physical arrangement matches the written record.

Include the system in internal audits and management review. Useful measures include the percentage of storage units with current temperature records, expired items found during monthly checks, stock discrepancies, emergency purchases, rejected deliveries and the number of temperature excursions. Trends are more informative than a single result. Repeated expiry waste may indicate poor forecasting, while frequent stockouts may show that the minimum level is too low.

Review the map after equipment replacement, room renovation, a new test method, supplier change or a significant incident. The GLI Quality Tool’s continual improvement guidance is relevant when a laboratory uses audit results, staff feedback and nonconformity data to strengthen its storage process. In Australia, also review arrangements before periods of extreme heat, cyclone disruption, bushfire risk or extended public holiday closures.

A well-designed storage map is a working quality document, not a decorative diagram. It links each product to a safe location, a defined status, a temperature requirement and an expiry decision. Establish the zones, label the locations, train the team and verify the arrangement during routine stock control so every TB reagent and media component remains fit for purpose when testing is required.