How to Standardise Filter Part Numbers Across Several Buildings

If you manage several buildings, filter ordering can become messy fast. One site uses a legacy code, another uses a supplier’s shorthand, and a third has measurements written in a maintenance spreadsheet that no one wants to trust. Standardising part numbers brings those systems together so your team can order the right filter more consistently and with less back-and-forth.

Why part-number standardisation matters

When every building, plant room or tenancy uses a different naming system, small errors can turn into repeated misorders. A part number that looks familiar may still refer to the wrong depth, frame, media grade or seal type.

A standard part-number system gives your team one reference point for each filter type. That helps when:

• •multiple buildings use different legacy naming conventions
• •the same filter is supplied by more than one vendor
• •drawings, handover packs and maintenance records do not match
• •staff changes mean knowledge is not carried from one person to the next
• •you need a clear list for procurement, site stores or contractors

For property and facility managers, the aim is not to change the filter itself. The aim is to make the ordering language consistent, so everyone is working from the same reference.

Start by building a master filter register

Before you rename anything, gather every filter code currently in use across the portfolio. Include the labels from the unit itself, old spreadsheets, commissioning documents, service reports and supplier invoices.

Your master register should record the details that actually define the filter:

• •building name and location
• •air handling unit or equipment reference
• •filter stage, such as pre-filter, final filter or panel filter
• •dimensions in millimetres
• •frame material and construction style
• •media type and any stated rating
• •seal, gasket or pocket style where relevant
• •current supplier code and any legacy code
• •notes about special installation details

Where possible, compare the written code against the physical filter and the housing. If a size is unclear, measure the existing filter carefully and confirm the installation space. If you need a refresher, see how to measure an air filter.

Create one naming format and stick to it

A good part-number system is simple enough for procurement staff, technicians and contractors to use without interpretation. The format should always tell the reader the same things in the same order.

Many organisations use a structure that includes:

• •site or building identifier
• •equipment identifier
• •filter stage
• •nominal size
• •media or rating detail
• •special construction notes
• •revision or version marker

The exact format is up to your organisation, but consistency matters more than complexity. A long code can still work well if every section has a clear purpose. The important thing is that the same filter always has the same master part number, even if a supplier uses a different internal code.

It is also worth creating a short glossary for anyone placing orders. If a term like “bag”, “pocket”, “panel” or “pre-filter” is used differently across sites, define it once and use that wording in all records.

Map legacy sizes and supplier codes into the new system

Once you have a master format, create a mapping document that links old codes to the new part number. This is the part that reduces ordering mistakes, because it shows how each historical code translates into your current system.

A practical mapping process includes:

• •listing every old code exactly as it appears in records
• •matching each code to one master part number
• •checking the physical filter size and frame type before approving the match
• •noting any supplier-specific wording that may hide the same product
• •flagging obsolete or unclear codes for review instead of guessing

If you manage multiple buildings, do not assume that similar codes mean the same thing. Two filters can look almost identical in paperwork but differ in depth, gasket style or airflow direction. If the housing is unusual, you may need a custom option rather than a close substitute. In that case, custom air filters can be the cleaner way to standardise the order process.

Where the same type of filter is used across several sites, assign one master code and then add site-specific notes only where needed. That keeps purchasing simple without losing the detail required for correct fitting.

Align records across procurement, maintenance and contractors

Standardisation only works if everyone uses the same information. If procurement, maintenance and external service teams each keep their own version of the filter list, the old confusion will return.

To keep records aligned:

• •store the master register in one controlled location
• •remove outdated codes from everyday ordering documents
• •label the equipment or storage location with the current part number
• •update contractor scope sheets and service instructions
• •keep a change log when a filter is superseded or revised

If you already use a service provider, ask them to quote from the master part number rather than from a loose description. That reduces the risk of “same size, wrong filter” orders.

For ongoing support, some sites also choose filter servicing or commercial filter servicing to keep replacement and inspection records in one place.

Build in checks for standards and site requirements

Standardising part numbers does not remove the need to confirm the technical requirements of the system. For ventilation and indoor air systems, site requirements should be checked with the mechanical services engineer or building owner, particularly where AS 1668.2:2024 is relevant.

It is also important not to treat rating systems as interchangeable. MERV, EN 779 and ISO 16890 do not convert directly, so avoid trying to force one standard into another with a rough table. If a site has existing EN 779 language such as G3, G4 or F5-F9, keep that notation in the records where it is still widely used, but make sure the master part number also captures the physical product details.

If a HEPA product is involved, record the grade exactly. H13 is at least 99.95% efficient and H14 is at least 99.995% efficient at the most penetrating particle size under EN 1822. That detail belongs in the part record so there is less risk of ordering the wrong class.

For any washable product, confirm the specific instructions. Some filters are designed to be washable, but you should always check the product instructions before cleaning or reusing them.

Keep the system easy to maintain

The best part-number system is one people actually use. If the structure is too complicated, staff will fall back to old habits or make their own short forms.

To keep it practical:

• •use plain, consistent naming across all sites
• •review the register when equipment is replaced or modified
• •keep photos of unusual filters with the code record
• •train new staff on the naming format during handover
• •reconcile the register against stock holdings and current plant lists

It also helps to review inspection frequency based on the system, site conditions and dust load. Follow the filter or equipment manufacturer instructions, and monitor pressure drop where gauges are fitted. That way the ordering system stays linked to what is actually happening on site, rather than to guesswork.

How Total Air Filtration can help

Total Air Filtration is a family-owned air filter manufacturer and supplier in Hillcrest, Brisbane QLD, and we work with facilities that need clear, repeatable filter references across more than one building. We can help you match legacy codes to a practical part-number system, supply the filters you need, or make the right filters to suit your equipment.

If you are tidying up your filter records or want help identifying a difficult size, call 07 3800 3448 or request a quote. You can also explore our products or contact us to talk through your site list.