How should pest control be managed in areas with restricted chemical use in pharmaceutical manufacturing plants?

Pharmaceutical factories contain many areas where chemical use needs to be very tightly controlled, particularly those associated with raw materials, production, packaging or finished-product storage. In these areas, the pest management programme needs to prioritise physical and mechanical measures, monitoring and entry prevention, while chemical treatment should only be considered after an appropriate assessment of risk and operating conditions.

1. Why do some areas in pharmaceutical factories need to restrict chemical use?

Pharmaceutical factories contain many areas that are sensitive to the risks of chemical residues, odours, vapours and cross-contamination. Therefore, pest management measures need to be selected in accordance with hygiene and safety requirements and the characteristics of each area.

Production areas, packaging areas, raw material warehouses, finished-goods warehouses and other areas with stringent quality-control requirements generally need to prioritise solutions that reduce reliance on spraying. This helps businesses control risk while maintaining stable operating conditions.

For pest management in areas with restricted chemical use, the objective is to prevent pests from gaining access at an early stage, quickly detect abnormal signs and address the actual cause on site.

For pharmaceutical factories, chemical restrictions need to be considered within the quality management system and the GMP requirements currently applied at the facility. The QA team can refer to GMP requirements related to sanitation, contamination prevention and pest management to determine the appropriate scope of control for each area.

2. Start by preventing pest entry

Prevention is the most important layer of control in sensitive areas. Doors, gaps at the base of walls, pipes passing through walls, service openings, ceilings and points adjoining the outside environment need to be reviewed periodically.

Appropriate gaps can be sealed using materials compatible with the building structure. Screens installed at ventilation openings, service gaps or other suitable locations also help reduce the likelihood of insects and small animals entering.

When entry routes are well controlled, pest pressure on interior areas decreases significantly, thereby reducing the need for chemical treatment. For factories renovating production lines or expanding production areas, wall penetrations, service gaps and junction points should be reviewed from the design stage.

See more: How to integrate pest-prevention measures into factory construction and renovation to limit entry routes that are difficult to correct once the facility is operational

3. Manage doors and transition areas

Entrances, receiving and dispatch areas, buffer warehouses and transition corridors are locations where pests can move from the outside environment into controlled areas.

The factory needs to keep doors closed when not in use and inspect the sealing condition of gaskets, curtains and other protective components. If the area has a high flow of people and goods, inspection frequency also needs to increase accordingly.

This is a very important layer of control because once pests have moved deeper inside the facility, treatment becomes much more complex than preventing entry at transition areas.

In addition to the condition of doors and sealing components, the factory needs to consider the risk of pests being introduced on pallets, cartons or packaging from suppliers. You can refer to guidance on identifying pest risks at the raw material and packaging receiving stage to incorporate this into the incoming-inspection procedure.

4. Use appropriate mechanical traps and monitoring devices

In areas with restricted chemical use, mechanical traps are an appropriate solution for many rodent-control situations and certain other pest groups.

For rodents, devices can be placed along wall edges, near doors or along routes showing signs of activity. Placement needs to be based on actual site assessment rather than uniformly spaced at fixed intervals.

For crawling insects, glue traps can support monitoring of insect density and help identify areas with activity. Trap data help businesses determine which points require further inspection before chemical intervention is needed.

5. Insect light traps should be used as monitoring tools

Insect light traps can support flying-insect monitoring in appropriate areas. However, their greatest value lies in the data collected across inspection cycles.

If an insect light trap records a continuous increase in the number of insects, the business needs to review nearby doors, light sources, external areas and surrounding operational activities.

Insect light traps also need to be positioned correctly to limit the attraction of insects from outside deeper into the factory. Placement should be based on insect movement routes and the sensitivity level of the area.

When selecting installation locations, the factory needs to consider insect movement routes, surrounding light sources and the sensitivity level of the area. Businesses can learn more about LED light-trap placement and the use of capture data to monitor flying insects before adjusting the existing system.

6. Control food sources and moisture

Cockroaches, ants and certain small insects often develop strongly where food, water or damp conditions are available. Therefore, sanitation is a direct part of the pest management programme.

The factory needs to control spilled materials, food in support areas, waste and points where water accumulates. Areas beneath equipment, rack bases, service gaps and locations that receive infrequent deep cleaning need to be included in the inspection schedule.

Reducing food sources and moisture makes the area less attractive to pests, thereby reducing the need for direct treatment measures.

Damp areas, sanitation areas, drains and concealed corners in warehouses often require closer inspection when cockroach signs are detected. Sanitation and maintenance teams can refer to 5 Cockroach hotspots in factories during hot and humid weather to develop a list of priority inspection locations.

7. Address harbourage areas

Small gaps behind equipment, electrical cabinets, technical ceilings, tool stores and low-traffic areas can become harbourage sites for cockroaches, rodents, lizards and other pests.

These locations need to be assessed and kept organised to reduce hiding places. Unused materials should be arranged appropriately, and sufficient clearance around wall edges needs to be maintained for observation.

When harbourage is reduced, the ability to detect pest signs also improves, helping businesses respond earlier.

For lizards, addressing harbourage needs to be combined with checking insect food sources and gaps leading into the building. The maintenance team can refer to the IPM-based guide to lizard control in factories to identify points requiring coordinated action.

8. Rodent control in areas with restricted chemical use

Rodents need to be managed according to entry routes and actual activity. The factory should monitor the outer perimeter first, followed by transition areas and then interior zones.

In sensitive areas, mechanical traps are generally more appropriate than chemical bait. Devices need to be placed in safe locations, clearly identified and inspected periodically.

When rodent signs are detected, the business needs to immediately inspect door gaps, pipes, food sources and nearby monitoring devices. The objective is to identify the route being used by rodents rather than simply increasing the number of traps.

9. Controlling cockroaches and ants without heavy reliance on spraying

Cockroaches and ants are often closely associated with food sources, moisture and gaps. Therefore, businesses should begin by identifying movement routes and harbourage sites.

Glue traps can be used for monitoring, while gaps and damp areas need to be addressed through structural and sanitation measures.

If pest-control products need to be used, the location and method need to be selected according to the level of risk and the factory’s internal requirements. Targeted treatment at the correct point is generally more appropriate than broad spraying in sensitive areas.

This is the difference between treating insects when they are seen and managing pests based on the cause. Businesses can learn more about how IPM differs from traditional insect spraying to understand why sanitation, entry prevention and monitoring often need to be prioritised before chemical intervention is considered.

10. When can chemical use be considered?

Chemical use may be considered when assessment shows that physical, mechanical and sanitation measures are not sufficient to control the problem.

Before use, the area, scope, application time, type of pest-control product and the time at which the area may be used again need to be clearly defined. These steps should be agreed with QA, HSE and the operations team.

Each use needs to be clearly recorded for traceability. This helps the business control risk more effectively and avoid unsupported chemical use in sensitive areas.

11. The role of data in areas with restricted chemical use

When chemical measures are used less frequently, monitoring data become more important. The number of insects on traps, rodent signs, locations of occurrence and frequency of occurrence need to be tracked across multiple inspection cycles.

If a point shows a continuous increase, the business can intervene early through sanitation, sealing gaps or adjusting devices. This is a way to reduce risk before stronger measures are required.

The PestMan App and PestMan Dashboard can support data recording by location, retain historical records and help QA monitor trends more clearly.

12. Zoning by sensitivity level

Not all areas with restricted chemical use have the same level of risk. Production areas, packaging areas and finished-goods warehouses generally require tighter control than corridors or support areas.

Zoning helps businesses determine which measures should be prioritised in each area. Highly sensitive zones may focus on monitoring and physical measures, while external areas may allow a broader range of control options.

This approach helps the pest management programme reflect actual conditions rather than applying the same method throughout the entire factory.

13. Common mistakes in pest management for areas with restricted chemical use

A common mistake is relying too heavily on traps without addressing gaps. When entry routes remain open, pests can continue to enter.

Another mistake is placing traps without reviewing the data. Devices are only valuable when the data are analysed and lead to specific actions.

In addition, allowing materials to block traps, failing to update device locations after layout changes or overlooking technical areas can also reduce programme effectiveness.

Discrepancies in device locations, maps, data and corrective actions can also create difficulties when QA needs to retrieve evidence during an audit. Responsible teams should refer to 5 pest-control documentation errors that are easily detected during factory audits for self-review before the audit team arrives on site.

14. How should QA and HSE coordinate?

QA typically monitors impacts on quality and traceability requirements, while HSE focuses more on methods, safety and chemical use.

Maintenance is responsible for addressing gaps, doors and structural issues. Sanitation controls food sources and environmental conditions. The pest control provider conducts assessments, monitoring and recommends technical control measures.

When an abnormality is identified, the report needs to clearly indicate which department is responsible for the next step so that the issue is not merely recorded without being addressed.

Frequently Asked Questions

Can pests in areas with restricted chemical use be controlled entirely through mechanical measures?

In many cases, mechanical, physical and sanitation measures can control a large proportion of the risk. Their effectiveness depends on the pest type, current conditions and the ability to prevent entry.

Should rodent bait be used in pharmaceutical production areas?

Its use needs to be evaluated according to internal requirements, level of risk and location. Sensitive areas generally prioritise mechanical traps and control of entry routes.

Can insect light traps replace inspection of doors and gaps?

No. Insect light traps are monitoring tools, while doors and gaps still need to be addressed to reduce entry routes.

When should inspection frequency be increased?

When data show an increase in pest density, after layout changes, the addition of new doors or equipment, or repair activities that alter the structure.

Do inspection cycles with no pest findings also need to be recorded?

Yes. Stable data across multiple inspection cycles help businesses demonstrate that the programme is maintaining effectiveness and support trend evaluation.

Effective pest management in areas with restricted chemical use begins with prevention

Pest management in areas with restricted chemical use needs to focus on preventing entry, managing food sources, reducing harbourage, using mechanical traps and monitoring data.

This approach helps pharmaceutical factories reduce reliance on chemicals, maintain control in sensitive areas and respond early when abnormal signs are detected. When intervention with pest-control products is required, their use also has a clearer basis in data and actual risk assessment.

If businesses are looking for a pest control company for businesses, need to survey the current pest situation or build a control program suitable for a factory, warehouse, hotel, or building, VFC PestMan can assist with on-site evaluation and propose solutions based on actual risks.

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Email: contact@pestman.vn