How to Investigate Factory Indoor Air Quality Complaints Malaysia
Meta Description: Learn how to investigate factory indoor air quality complaints involving stuffiness, dust, chemical odours, headaches, temperature and poor ventilation in Malaysia.
How to Investigate Factory Indoor Air Quality Complaints Malaysia
Employees may report that a factory office, control room or production area feels stuffy, dusty, hot, humid or affected by chemical odours.
These complaints should not be dismissed simply because the room appears clean or the air-conditioning is operating. Indoor air problems may be caused by insufficient outdoor air, dust, VOCs, formaldehyde, temperature, humidity, microbial contamination or pollutants entering from a nearby production process.
A structured indoor air quality investigation helps the factory identify when, where and under which operating conditions the problem occurs.
Common Factory Air Quality Complaints
Employees may report:
Stuffy or stale air
Chemical smell
Dusty conditions
Eye or throat irritation
Headache
Dizziness
Unusual tiredness
Excessive heat
High humidity
Dry air
Discomfort near an air-conditioning outlet
Symptoms that improve after leaving the room
These symptoms are not specific to one pollutant. Measurement and further investigation are needed before deciding on the cause.
First Question: Is It an Emergency?
Before starting a routine IAQ investigation, determine whether the complaint may involve an immediate hazard.
Possible emergency warning signs include:
Gas-detector alarms
Strong or rapidly increasing chemical odour
Several workers becoming unwell suddenly
Visible smoke or vapour
Suspected refrigerant leakage
Suspected ammonia or combustible-gas leakage
Loss of consciousness
Breathing difficulty
Oxygen-deficiency concern
Personnel should follow the factory emergency procedure and move to a safe location when an immediate gas or chemical hazard is suspected.
A general indoor-air-quality monitor should not be used as the only instrument for emergency gas detection.
Step 1: Record the Complaint Properly
Useful information includes:
Exact location
Date and time
Symptoms or type of discomfort
Number of employees affected
When the complaint started
Whether it occurs every day
Production activity at the time
Chemicals being used
Air-conditioning condition
Doors and windows open or closed
Whether symptoms improve outside the area
A vague record such as “office air not good” provides little information for troubleshooting.
Step 2: Inspect the Area
Conduct a visual inspection before taking measurements.
Check for:
Blocked supply or return-air grilles
Dirty filters
Water leakage
Condensation
Visible mould
Dust accumulation
Chemical containers
New furniture
Recent renovation
Open drains
Exhaust outlets near fresh-air intakes
Production fumes entering the room
Unusual odours
Excessive occupancy
Ventilation fans that are not operating
The inspection helps determine which parameters should be measured.
Step 3: Identify the Likely Pollutants
Different complaints require different instruments.
Stuffy Room
Consider measuring:
CO鈧
Temperature
Relative humidity
Air velocity
Dust or Haze
Consider measuring:
PM2.5
PM10
Airflow
Differential pressure across filters
Chemical Odour
Consider measuring:
TVOC
Formaldehyde, where relevant
Specific gases based on the chemicals used
Hot or Humid Conditions
Consider measuring:
Temperature
Relative humidity
Air movement
Heat stress where applicable
Suspected Combustion
Consider measuring:
Carbon monoxide
Oxygen where required
Combustible gases where applicable
One multi-parameter monitor can support initial screening, but specific hazards may require dedicated detectors.
Step 4: Compare the Complaint Area
A reading becomes more useful when it can be compared with another condition.
Compare:
Complaint area vs unaffected area
Indoor vs outdoor
Before production vs during production
Low occupancy vs peak occupancy
Ventilation off vs ventilation on
Door closed vs normal door operation
Before maintenance vs after maintenance
Morning vs afternoon
The comparison may show whether the problem is related to occupancy, production, outdoor pollution or ventilation.
Step 5: Measure CO鈧 for Ventilation
CO鈧 is useful for assessing occupancy-related ventilation performance.
A rising CO鈧 trend may indicate:
Insufficient outdoor air
High occupancy
Closed dampers
Ventilation fans not operating
Inadequate ventilation scheduling
Poor air distribution
Place the monitor in the normal occupied zone rather than directly beside an open window or fresh-air outlet.
CO鈧 is not a complete air-safety measurement. Low CO鈧 does not rule out dust, VOCs or toxic gases.
Step 6: Measure PM2.5 and PM10
Particulate monitoring is useful when complaints involve dust, haze or production emissions.
Possible sources include:
Grinding
Cutting
Welding
Sanding
Powder handling
Vehicle movement
Outdoor pollution
Dirty ventilation systems
Construction or renovation
Measure during the activity suspected of generating the particles.
Portable Temtop monitors can compare particulate conditions across several factory areas and help identify where readings increase.
Step 7: Measure TVOC and Formaldehyde
TVOC and HCHO monitoring may be relevant when the area contains:
Paint
Solvents
Adhesives
Cleaning chemicals
New furniture
Engineered wood
Renovation materials
Printing ink
Chemical storage
The Temtop LKC-1000S+ can monitor HCHO, TVOC, PM2.5 and PM10 for general air-quality screening.
An elevated reading should be investigated together with the chemical inventory, Safety Data Sheets, ventilation condition and possible sensor interference.
Step 8: Check Temperature and Humidity
Thermal discomfort can produce complaints even when pollutant readings appear normal.
Check whether:
The area is too warm or cold
Humidity is persistently high
Air is blowing directly onto employees
Temperature varies significantly between workstations
Conditions change throughout the shift
Heat-producing equipment affects the room
Condensation or moisture is present
A temperature and humidity data logger can show conditions over several hours or days rather than only at the moment of inspection.
Step 9: Measure Air Velocity
An anemometer can help determine whether air is moving through:
Supply-air outlets
Return-air grilles
Exhaust ducts
Workstation extraction hoods
Fresh-air intakes
The Benetech GM8903 hot-wire anemometer is suitable for air-velocity and airflow checks in ducts and ventilation openings.
Air velocity alone does not confirm indoor-air quality, but it can reveal ventilation problems that contribute to pollutant buildup.
Step 10: Monitor the Trend
Many IAQ problems occur only under particular conditions.
Continuous or data-logging measurements can reveal:
CO鈧 increasing during meetings
PM rising when production starts
TVOC increasing during cleaning
Humidity rising overnight
Temperature increasing in the afternoon
Pollutants remaining elevated after ventilation stops
A fixed system such as a suitable Fosensor FS11301 configuration may be used when continuous monitoring is required at a confirmed location.
Portable instruments should normally be used first when the problem source is still unknown.
Recommended Investigation Sequence
A practical sequence is:
Record the complaint.
Determine whether an immediate hazard exists.
Inspect the room and ventilation system.
Identify the likely pollutants.
Conduct portable measurements.
Compare affected and unaffected conditions.
Record production, occupancy and ventilation status.
Review the data trend.
Correct the suspected source or ventilation problem.
Repeat measurements after corrective action.
Arrange a professional assessment where necessary.
Install fixed monitoring if the area requires continuous observation.
This prevents the factory from purchasing a permanent monitor before understanding the actual problem.
Portable vs Fixed Monitoring
Start with Portable Monitoring When:
The complaint location varies
The source is unknown
Several parameters must be screened
Different rooms need comparison
The factory is troubleshooting
Consider Fixed Monitoring When:
The problem occurs repeatedly at one location
Continuous data is required
Employees need a visible warning
Ventilation control is planned
Long-term trends are important
Portable monitoring finds the problem. Fixed monitoring manages a known critical location.
Malaysia Indoor Air Quality Investigation
DOSH Malaysia describes an IAQ complaint investigation as generally involving five main activities:
Initial visit
Measurement of contaminants
Data analysis
Discussion with the employer
Preparation of a report
The official information and Industry Code of Practice on Indoor Air Quality 2010 are available from the DOSH Malaysia indoor air quality portal.
Measurements taken by internal maintenance staff are useful for preliminary screening, but they do not automatically replace an assessment by the appropriate competent person when a formal investigation is required.
Common IAQ Investigation Mistakes
Measuring Without Recording the Activity
A reading cannot be interpreted properly without knowing what was happening.
Testing Only After Employees Leave
Occupancy-related CO鈧 or production emissions may already have decreased.
Using One Instrument for Every Hazard
A TVOC monitor cannot replace an ammonia detector, oxygen monitor or four-gas detector.
Placing the Monitor Beside Fresh Air
This may hide the actual condition in the occupied zone.
Assuming Air-Conditioning Means Good Ventilation
Some systems mainly recirculate indoor air.
Looking Only at Instantaneous Readings
Short measurements may miss recurring peaks.
Installing Fixed Monitoring Too Early
First determine the pollutant and correct monitoring location.
Ignoring Employee Information
The time and location of complaints often provide valuable clues.
Useful Instruments for Factory IAQ Investigation
Depending on the complaint, an investigation toolkit may include:
Multi-parameter air-quality monitor
CO鈧 monitor
PM2.5 and PM10 monitor
TVOC and formaldehyde monitor
Temperature and humidity logger
Hot-wire anemometer
Differential-pressure meter
Carbon-monoxide detector
Specific toxic-gas detector
Four-gas detector
The required combination depends on the process and suspected hazard.
Factory Indoor Air Quality Monitoring Supplier Malaysia
MTM Precision supplies portable and fixed indoor-air-quality monitoring instruments for factories, offices, control rooms, laboratories and industrial workplaces in Malaysia.
Available solutions include Temtop air-quality monitors, Benetech airflow meters, gas detectors, data loggers and selected Fosensor fixed-monitoring configurations.
Contact MTM Precision with details of the complaint, factory process, room type and suspected pollutants to discuss a suitable monitoring approach.
Contact MTM Precision
MTM Precision Sdn. Bhd.
Showroom & Service Centre
No. 29-1 & 29-2, Jalan Bandar 18,
Pusat Bandar Puchong,
47160 Puchong, Selangor, Malaysia
馃寪 Website: www.mtmpre.com.my
馃摟 Email: mtmpre@yahoo.com
馃摫 WhatsApp: +6016-660 7346
01 Sep 2026
