GLI GLI Quality Tool
GLI Quality Tool — Version 2.0

Writing a Controlled TB Reagent Procedure That Stands Up to Audit

A well-written tuberculosis laboratory procedure makes reagent preparation consistent, traceable and safe, whether the work is performed in a metropolitan reference laboratory or a small service supporting remote communities. The document should tell staff exactly what to do, what to record and when to stop the process if a requirement is not met.

Reagent control is closely linked to reliable TB testing. Incorrect volumes, expired components, unclear labels or an unchecked calculation can affect culture, microscopy, molecular testing and quality control. A two-person verification step adds an independent check at the point where errors are easiest to prevent, provided the procedure clearly defines both people’s responsibilities.

Define The Procedure’s Scope And Accountability

Start by stating which reagents the procedure covers. It may apply to prepared media, stains, buffers, decontamination solutions, molecular assay reagents, quality control materials or working solutions made from commercial concentrates. Identify whether it covers preparation from raw chemicals, reconstitution of supplied products, dilution, aliquoting, labelling, storage and disposal.

The scope should also explain where the procedure applies and who may perform each activity. A laboratory assistant might gather materials and complete the preparation record, while an authorised scientist checks calculations and confirms the final label. In a smaller Australian service, one person may prepare the reagent during a quiet shift and a second trained staff member may verify it later. The procedure must state whether delayed verification is acceptable and how the material remains quarantined until approval.

Assign document ownership to a named role rather than an individual’s name. The quality manager, section supervisor or laboratory manager should approve the controlled version, set the review date and authorise changes. Include related documents such as the safety data sheet, equipment instructions, validated test method, waste procedure and incident reporting process. The GLI Quality Tool provides a useful quality management framework for connecting this procedure with document control, personnel, equipment and assessment activities.

Set Out Preparation Controls In Plain Language

The operational section should follow the actual sequence of work. Begin with hand hygiene, personal protective equipment, workspace preparation and a check that the required equipment is clean, suitable and within calibration. Specify the balance, pipettes, measuring cylinders, water quality, mixing equipment and temperature controls required for each reagent. If work involves potentially infectious material, distinguish reagent preparation from procedures involving viable M. tuberculosis and refer staff to the laboratory’s approved biosafety controls.

Write quantities with units, concentrations and acceptable tolerances. A statement such as “add the required amount of water” is too vague for a controlled procedure. Use exact instructions, for example: “Add 900 mL of purified water, mix until dissolved, then adjust to a final volume of 1,000 mL.” State whether the final volume is measured at room temperature and whether pH adjustment occurs before or after volume is made up.

Include preparation calculations or attach an approved worksheet. The worksheet should show the stock concentration, target concentration, final volume and calculation used. Staff should never rely on memory or an informal formula written on scrap paper. If a reagent is reconstituted according to a manufacturer’s instructions, record the product name, lot number, expiry date, reconstitution volume and any required hold time.

Australian laboratories may receive supplies through state or territory procurement systems, contracted distributors or centralised public health stores. That can mean different pack sizes, substitute brands or delivery delays. The procedure should require staff to check the approved supplier and current product specification before substituting any component. A change in manufacturer, formulation or container may require verification before routine use.

Make Two-Person Verification A Defined Hold Point

Two-person verification should be a genuine independent control, not a second signature added after the work is complete. The preparer performs the calculation, gathers the materials and makes the reagent. The verifier checks the source documents, calculations, component identity, lot and expiry information, equipment status, preparation steps and final container before release.

Define what the verifier must physically inspect. They should compare the container against the preparation record, confirm that the label is complete and legible, check the final appearance where applicable and verify storage conditions. If the procedure requires pH, sterility, concentration or another acceptance test, the verifier should confirm that the result meets the stated criterion or that the reagent remains quarantined pending testing.

The two people should not copy each other’s work. The verifier should independently recalculate critical quantities and review the original source, such as the approved formula or manufacturer’s instructions. Electronic systems can support this process with separate logins, audit trails and mandatory fields, but a shared password or pre-signed record defeats the purpose.

Set out the response to a discrepancy. The reagent must be labelled “Do Not Use” or placed in a physically separated quarantine area while the issue is investigated. The record should identify the error, affected lot or batch, staff involved, action taken and final disposition. If an incorrect reagent has already been used, the laboratory should assess affected testing, notify the relevant supervisor and follow its nonconformance procedure.

Design Labels And Records For Traceability

A reagent label should allow a person who was not involved in preparation to identify and use the material safely. At minimum, include the reagent name, concentration or strength, preparation date, expiry or discard date, lot or batch number, storage conditions, preparer initials and verifier initials. Add hazard information, biohazard status, light protection requirements and “For laboratory use only” wording where relevant.

The label must match the preparation record exactly. Avoid abbreviations that could be misunderstood, particularly when similar reagents have different concentrations. Use a label template that supports clear printing and remains attached at the temperatures and humidity expected during storage. For small tubes, use a secondary container or linked worksheet rather than shrinking essential information until it cannot be read.

The preparation record should capture the source and identity of every critical component. Record chemical or product name, catalogue number where relevant, manufacturer, lot number, expiry date, quantity used, water type, equipment identification and any test results. Include the storage location and the date the reagent was placed into service. A unique batch number can link the container to the worksheet, inventory record and any incident investigation.

Storage instructions need practical detail. State the temperature range, protection from light, maximum open-container period and whether repeated freeze-thaw cycles are prohibited. In Australia, a reagent transported between a city laboratory and a regional or remote service may experience long road distances and seasonal heat, including routes through Far North Queensland or the Northern Territory. The procedure should identify approved transport conditions and what to do if a temperature excursion occurs.

Connect The Procedure To Ongoing Quality Improvement

Before approval, test the procedure with the staff who will use it. Ask a trained preparer to follow the document without verbal prompts and observe where interpretation is difficult. Check whether the form has enough space for calculations, whether labels fit the available containers and whether the verification step can be completed during normal rostered hours.

Training records should show who was trained, which version was used and whether competency was assessed. Competency may include observing preparation, completing a calculation, selecting suitable PPE, producing a compliant label, identifying a deliberately introduced discrepancy and documenting the final decision. Refresher training is appropriate after a major change, recurring error or extended period away from the task.

Use internal audits, incident reports, failed quality control results, stock wastage and staff feedback to review the procedure. A high rate of discarded reagents may indicate unclear expiry rules, unsuitable batch sizes or problems with storage. Repeated labelling errors may point to a poor template rather than individual carelessness. Record the root cause, corrective action, responsible person and effectiveness check.

For laboratories progressing through a quality management roadmap, procedure review should sit within a broader cycle of measurement and improvement. The continual improvement phase can help laboratories organise evidence that changes are based on findings, implemented in a controlled manner and checked for sustained effect.

Practical Checks For Release And Review

Use the following recommendations when drafting, approving or revising the controlled procedure:

Use controlled templates for the preparation worksheet, label and verification record so staff do not create informal versions at the bench. Keep obsolete forms unavailable for routine use, retain completed records according to the laboratory’s retention policy and protect records from unauthorised alteration.

A strong procedure should be usable during a busy shift, an after-hours roster or a handover between teams. In a large service such as a state reference laboratory, it should work across sections and campuses. In a smaller regional laboratory, it should still be practical when only a few authorised staff are available. Clear language, defined hold points and complete records make the process dependable in both settings.

Update the document, train the affected staff and place the new version into controlled use. Then observe the first preparations, review the completed verification records and correct any weakness before it becomes routine. Build reagent preparation and labeling with two-person verification into everyday laboratory practice so each container carries visible evidence of its identity, quality and release decision.