Factory Haze and PM2.5 Monitoring in Johor Malaysia
Meta Description: Learn how Johor factories can prepare for haze, monitor PM2.5 across work areas, test filtration and distinguish outdoor particle entry from industrial dust sources.
Factory Haze and PM2.5 Monitoring in Johor Malaysia
Factories in Johor should prepare for haze before outdoor air quality becomes unhealthy.
Industrial buildings often have:
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Large entrances
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Roller shutters
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Loading bays
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Roof ventilation
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Mechanical air systems
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Frequent vehicle movement
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Multiple production and office zones
These features can allow outdoor particles to enter quickly.
A portable PM2.5 air quality monitor helps factory management compare work areas, check air purifier performance and identify locations that may require additional investigation.
Official Air Pollutant Index—API—information remains the main reference for regional air quality and government instructions.
Why Factory PM2.5 Monitoring Is Different From Home Monitoring
A factory may contain particles from both outdoor and internal sources.
Possible outdoor sources include:
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Haze
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Road traffic
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Nearby industrial activities
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Open burning
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Vehicle exhaust
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Construction
Possible internal sources include:
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Grinding
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Cutting
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Welding
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Sanding
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Powder handling
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Combustion
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Forklift operation
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Material transfer
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Cleaning
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Packaging
A general PM2.5 monitor measures the particle concentration around its sensor. It cannot automatically identify whether the particles came from haze or a factory process.
API vs Factory PM2.5
| Official API | Factory PM2.5 Monitor |
|---|---|
| Regional outdoor air-quality information | Local workplace measurement |
| Reported as an index | Normally reported in µg/m³ |
| Based on official stations | Based on the instrument’s location |
| Supports public and workplace guidance | Supports internal investigation |
| Cannot represent every work area | Can compare factory zones |
Factories should use the two sources for their intended purposes.
Which Factory Areas Should Be Checked?
Recommended monitoring locations include:
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Administration offices
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Control rooms
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Production areas
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Maintenance workshops
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Worker rest rooms
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Warehouses
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Loading bays
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Canteens
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Security posts
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Areas near roller shutters
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Rooms with air purifiers
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Rooms where complaints occur
One reading from the management office cannot represent the entire factory.
Build a Factory Monitoring Map
Divide the premises into zones:
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Outdoor reference area
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Administration area
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Production zone
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Control room
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Maintenance workshop
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Warehouse
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Loading bay
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Worker rest area
Mark suspected entry points and internal particle sources.
This creates a repeatable monitoring route instead of a collection of random measurements.
Establish Baseline Readings Before Haze
Record normal conditions before an air-pollution event.
Useful baseline information includes:
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PM2.5
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PM10
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Location
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Work activity
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Number of occupants
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Door and shutter status
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Ventilation status
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Air-conditioning status
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Air purifier status
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Outdoor API
Baseline readings help management recognise unusual changes during haze.
Correct Instrument Placement
Place the PM2.5 monitor:
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In a representative occupied area
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At a suitable breathing-zone height
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Where air can circulate around the sensor
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On a stable surface
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Away from excessive heat, water and impact
Avoid positioning it:
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Directly beside a process exhaust
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Next to a dust-producing machine
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In front of an air purifier
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Under an air-conditioning outlet
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Beside vehicle exhaust
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Inside a cabinet
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In an unsafe work area
When investigating a source, take one reading near the suspected source and another at the normal worker position.
Suggested Monitoring Procedure
Step 1: Check the Official API
Record the current API for the nearest relevant Johor location.
Include the date and time.
Step 2: Record Factory Operations
Note whether the factory is undergoing:
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Normal production
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Loading
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Cleaning
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Maintenance
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Shift change
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Production shutdown
Step 3: Measure Each Selected Zone
Allow the instrument to stabilise according to the manufacturer’s instructions before recording the value.
Step 4: Record the Conditions
Note doors, shutters, ventilation, air-conditioning and purifier operation.
Step 5: Repeat the Survey
Repeat when:
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The API changes
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A different shift begins
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Loading starts
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Filters are replaced
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Ventilation changes
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A production process starts or stops
Example Factory PM2.5 Record
| Time | Area | PM2.5 | PM10 | Activity | Shutter | Ventilation |
|---|---|---|---|---|---|---|
| Record | Administration office | Record | Record | Normal work | Closed | Record |
| Record | Control room | Record | Record | Normal operation | Closed | Record |
| Record | Production area | Record | Record | Record process | Record | Record |
| Record | Warehouse | Record | Record | Storage/loading | Open/Closed | Record |
| Record | Rest area | Record | Record | Occupied | Closed | Record |
Use actual readings and record any unusual events.
How to Identify Outdoor Haze Entry
Compare PM2.5 at:
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Outdoor reference point
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Immediately inside an entrance
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Centre of the factory
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Administration office
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Enclosed control room
Repeat the comparison when a shutter is:
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Open
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Partly open
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Closed
Only change operating conditions when it is safe and permitted.
If readings are highest near the entrance and decrease toward enclosed rooms, outdoor particle entry may be contributing significantly.
How to Distinguish Haze From a Process Source
A portable monitor cannot identify particle composition, but comparisons may provide useful clues.
Measure:
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Before production begins
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During production
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After production stops
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Near the process
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Away from the process
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Indoors and outdoors
Record the process, wind direction, ventilation and door status.
If PM2.5 rises only when a particular process operates, the process may require further investigation.
This is a screening observation—not a formal source determination.
Checking Air Purifiers in Enclosed Rooms
Air purifiers may be used in:
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Control rooms
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Administration offices
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Meeting rooms
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Worker rest rooms
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Cleaner indoor areas
To test:
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Position the monitor away from the purifier.
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Record the initial PM2.5.
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Switch on the purifier.
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Record the fan speed.
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Keep the room conditions consistent.
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Measure at regular intervals.
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Repeat at the point furthest from the purifier.
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Review the trend.
If there is little improvement, check purifier capacity, filter condition, room size, leakage and door-opening frequency.
Reviewing HVAC Filtration
An air-conditioned room is not automatically protected from haze.
Fine particles may enter through:
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Fresh-air intake
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Poorly fitted filters
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Dirty filters
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External doors
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Building gaps
Measure PM2.5 before and after filter maintenance using the same location and comparable operating conditions.
This can indicate whether maintenance produced a measurable change, but it does not certify HVAC performance.
Why Control Rooms May Need CO₂ Monitoring
A closed control room can have lower PM2.5 than the production floor but higher CO₂ during occupancy.
PM2.5 and CO₂ represent different conditions:
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PM2.5: Fine-particle concentration
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CO₂: A parameter associated with occupancy and ventilation
The Temtop M2000 2nd measures both and may be suitable for general control-room assessment.
When Are HCHO and TVOC Relevant?
HCHO and TVOC screening may be relevant in:
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Newly renovated offices
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New control rooms
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Rooms with new furniture
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Areas using adhesives
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Coating-related environments
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Areas where chemical odours are reported
The Temtop LKC-1000S+ 2nd combines PM2.5 and PM10 with HCHO and TVOC screening.
A general TVOC monitor does not identify specific compounds.
Spot Checks or Data Logging?
Spot Checks
Useful for:
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Comparing zones
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Finding particle-entry points
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Testing air purifiers
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Checking after filter replacement
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Preliminary complaint investigation
Data Logging
Useful for:
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Monitoring an entire shift
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Identifying loading-related spikes
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Comparing day and night conditions
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Reviewing production cycles
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Tracking haze entry
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Documenting filtration changes
Data logging is particularly useful when the source or timing of the increase is unclear.
Which Temtop Monitor Is Suitable?
Temtop M2000 2nd
Measures:
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PM2.5
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PM10
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CO₂
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HCHO
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Temperature
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Humidity
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Data export
Suitable for control rooms, offices and other occupied enclosed spaces.
Temtop LKC-1000S+ 2nd
Measures:
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PM2.5
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PM10
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HCHO
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TVOC
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Temperature
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Humidity
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Data export
Suitable for general particulate and chemical-pollutant screening.
Temtop M10i
May be suitable for compatible Wi-Fi monitoring in a fixed indoor location, subject to the supplied version.
General Monitor vs Occupational Testing
A portable indoor air quality monitor is useful for:
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General screening
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Baseline measurement
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Area comparisons
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Haze monitoring
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Air purifier checks
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Maintenance evaluation
It may not be sufficient for:
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Personal exposure sampling
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Workplace exposure limit verification
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Respirable crystalline silica
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Specific chemical analysis
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Regulatory compliance
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Process emission testing
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Legal exposure documentation
These applications may require specialised equipment and qualified professionals.
Common Factory Monitoring Mistakes
Assuming Every High Reading Is Caused by Haze
Factory processes may also generate particles.
Measuring Only During Production Shutdown
Normal operating conditions may be very different.
Monitoring Only the Office
Production, warehouse and loading areas require separate consideration.
Measuring Beside the Purifier
This may show clean outlet air rather than general room conditions.
Failing to Record Operations
Every reading should include the activity occurring at the time.
Using a General Monitor for Formal Compliance
Screening and regulatory testing are different.
Ignoring Official API Instructions
Local readings do not override government or workplace requirements.
Factory Haze Readiness Checklist
Before haze season, confirm:
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Official API sources identified
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Responsible staff assigned
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Baseline PM2.5 recorded
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Monitoring zones mapped
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Instruments checked and charged
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HVAC filters inspected
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Air purifiers tested
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Replacement filters available
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Cleaner rooms identified
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Outdoor tasks reviewed
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Respiratory-protection procedures checked
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Recording forms prepared
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Escalation contacts listed
Prepare Before Outdoor PM2.5 Rises
A prepared Johor factory should already understand:
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Its normal indoor particle levels
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Which areas are most affected by open entrances
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Whether enclosed rooms remain cleaner
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Whether air purifiers reduce PM2.5
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How production affects the readings
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When specialised testing is required
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Who records and reviews the data
Official API information provides the regional warning. Correctly conducted factory monitoring shows how individual work areas are affected.
Contact MTM Precision
Contact MTM Precision for assistance selecting a PM2.5 Air Quality Monitor for factories, warehouses and industrial workplaces in Johor Bahru, Pasir Gudang and Johor, Malaysia.
MTM Precision Sdn. Bhd.
Showroom & Service Centre
No. 29-1 & 29-2, Jalan Bandar 18,
Pusat Bandar Puchong,
47160 Puchong, Selangor, Malaysia
🌐 Website: www.mtmpre.com.my
📧 Email: mtmpre@yahoo.com
📱 WhatsApp: 016-660 7346
07 Sep 2026
