WBGT Heat Stress Monitoring for Solar Panel Installation Workers Malaysia

 

Malaysia's growing solar industry means more technicians are working on rooftops, open solar farms and exposed outdoor locations.

 

These workers may spend hours under direct sunlight while carrying tools, installing mounting structures, handling solar panels and performing electrical work.

 

During prolonged periods of hot weather, including conditions associated with El Niño, rooftop and solar-farm workers can face significant environmental heat exposure.

 

A WBGT Heat Stress Meter provides solar contractors, Safety and Health Officers, EHS teams and project managers with a practical method for measuring heat-stress conditions directly at the worksite.

 

Why Solar Installation Workers Face Heat Exposure

 

Solar installation combines several factors that can increase worker heat load:

 

Direct sunlight

 

High humidity

 

Limited shade

 

Physically demanding work

 

Safety helmets

 

Gloves and PPE

 

Long outdoor working periods

 

Heat radiating from rooftops

 

Hot metal mounting structures

 

Large exposed solar sites

 

Unlike many indoor occupations, solar workers are often positioned exactly where solar radiation is strongest.

 

This makes heat monitoring particularly relevant to the industry.

 

Rooftops Can Be Much Hotter Than Ground Level

 

Consider a commercial building.

 

At ground level, employees may have:

 

Shade + airflow + covered areas

 

On the rooftop, solar technicians may experience:

 

Direct sunlight + heated roof surfaces + limited shade + physical workload

 

The general weather temperature may be the same for both locations.

 

However, the thermal environments can be very different.

 

This is why heat conditions should ideally be measured where employees actually perform their work.

 

What Is WBGT?

 

WBGT stands for:

 

Wet Bulb Globe Temperature

 

WBGT is an environmental heat-stress index used to help evaluate thermal conditions affecting workers.

 

Depending on the instrument and measurement method, WBGT assessment can consider factors related to:

 

Natural wet-bulb temperature

 

Globe temperature

 

Air temperature

 

Humidity

 

Radiant heat

 

This makes a WBGT meter more appropriate for heat-stress assessment than relying only on an ordinary thermometer.

 

Why Is the Black Globe Important for Solar Work?

 

WBGT meters commonly feature a distinctive black globe sensor.

 

The globe helps assess radiant thermal conditions.

 

This is especially relevant on rooftops and solar farms because workers may receive radiant heat from:

 

Direct sunlight

 

and

 

surrounding heated surfaces.

 

Solar panels, roof materials, concrete and metal structures can all become hot under strong sunlight.

 

Therefore, solar workers may experience environmental conditions that are not fully represented by normal air-temperature measurements.

 

Which Solar Activities May Require Heat Monitoring?

 

WBGT monitoring can be relevant during:

 

Rooftop Solar Installation

 

Technicians can spend extended periods on exposed commercial, industrial and residential roofs.

 

Solar Farm Construction

 

Large utility-scale projects may require workers to remain outdoors throughout much of the working day.

 

Mounting Structure Installation

 

Handling rails, frames and structures can involve significant physical effort.

 

Solar Panel Installation

 

Panels must be transported, lifted and positioned, increasing worker workload.

 

Electrical Installation

 

Electricians may work in exposed locations while wearing appropriate PPE.

 

Testing & Commissioning

 

Engineers and technicians may spend long periods inspecting and testing completed installations.

 

Solar Maintenance

 

Existing solar systems require cleaning, inspection, troubleshooting and repair, often under the same exposed conditions.

 

Solar Workers Face Two Different Heat Problems

 

Solar contractors should distinguish between:

 

Worker Heat Stress

 

This concerns the thermal environment experienced by employees.

 

A WBGT Meter is relevant here.

 

Solar Panel Temperature

 

This concerns the surface temperature of the PV module or electrical components.

 

An Infrared Thermometer or Thermal Imager may be appropriate here.

 

These are different measurements.

 

For example:

 

WBGT Meter → Worker heat exposure

 

Infrared Thermometer → Panel/component surface temperature

 

Thermal Imager → Thermal inspection and hotspot investigation

 

A solar contractor may therefore use all three instruments for different purposes.

 

What About Solar Irradiance?

 

Solar irradiance is another separate measurement.

 

A Solar Irradiance Meter measures the solar energy reaching a surface.

 

It is useful for PV testing and solar-system assessment.

 

It should not be confused with WBGT.

 

A complete solar testing toolkit might therefore include:

 

WBGT Meter

Worker heat-stress monitoring

 

Solar Irradiance Meter

Solar radiation measurement

 

Infrared Thermometer

Surface-temperature checks

 

Thermal Imager

Thermal inspection

 

Multimeter / Clamp Meter

Electrical testing

 

PV Tester

Photovoltaic system testing

 

This creates an opportunity for solar companies to integrate occupational safety measurements with technical PV testing.

 

When Should Solar Contractors Measure WBGT?

 

Environmental heat conditions change throughout the day.

 

A rooftop may be relatively manageable early in the morning but become significantly hotter later.

 

For example:

 

8:00 AM — Lower solar exposure

 

10:00 AM — Increasing heat

 

12:00 PM — Strong solar exposure

 

2:00 PM — Potential high-heat period

 

4:00 PM — Roof surfaces may remain hot

 

Organizations should select representative measurement times according to actual working conditions and their applicable heat-risk procedures.

 

Measure on the Rooftop, Not in the Office

 

A common measurement mistake is choosing a convenient location rather than a representative one.

 

For example:

 

Site office: Air-conditioned

 

Ground floor: Shaded

 

Rooftop: Direct sunlight

 

If the technicians are working on the rooftop, measurements should represent rooftop conditions.

 

The same principle applies to solar farms.

 

A measurement taken inside a vehicle does not represent employees working between rows of PV panels.

 

Heat Stress and PPE

 

Solar technicians often require PPE for multiple hazards.

 

Depending on the task, this may include:

 

Safety helmet

 

Gloves

 

Safety footwear

 

High-visibility clothing

 

Fall-protection equipment

 

Long sleeves

 

Electrical PPE

 

Protective equipment may affect heat dissipation.

 

Therefore, workplace heat-risk assessment should consider environmental measurements together with PPE, workload and exposure duration.

 

Heat Monitoring for Solar Farms

 

Utility-scale solar farms present another challenge.

 

Workers may be spread across a large site.

 

Conditions can differ depending on:

 

Location

 

Shade

 

Wind

 

Ground surface

 

Time of day

 

Work activity

 

Portable WBGT meters allow safety personnel to check representative work areas rather than assuming one location describes the entire project.

 

El Niño 2026–2027 and Malaysia's Solar Workforce

 

During prolonged hotter and drier periods, solar contractors may experience more days where outdoor heat becomes an operational concern.

 

The solar industry is particularly exposed because the same sunny conditions that are favorable for solar generation can create challenging working environments for technicians.

 

Companies can prepare by establishing:

 

Baseline WBGT Measurements

 

↓

 

High-Heat Location Identification

 

↓

 

Routine Monitoring

 

↓

 

Measurement Records

 

↓

 

Heat-Risk Review

 

Starting before the hottest period allows the safety team to understand normal site conditions.

 

Using WBGT Data in Heat-Risk Management

 

WBGT measurements provide environmental information.

 

The organization's overall heat-management process may also consider:

 

Work intensity

 

Work/rest scheduling

 

Hydration

 

Shade

 

PPE

 

Acclimatization

 

Worker training

 

Exposure duration

 

Applicable occupational safety procedures

 

A WBGT meter does not replace professional safety assessment.

 

Instead, it provides measurement data that can support a structured heat-risk management process.

 

Tenmars WBGT Heat Stress Meters for Solar Contractors

 

Tenmars provides professional instruments suitable for workplace and outdoor heat monitoring.

 

Tenmars TM-288

 

Portable WBGT Heat Stress Meter suitable for rooftop, outdoor and occupational measurements.

 

Tenmars TM-188B

 

Heat Stress WBGT Meter featuring BLE wireless capability, useful for applications where wireless monitoring and data handling are required.

 

Tenmars TM-188D

 

Professional WBGT Heat Stress Meter for workplace and environmental heat monitoring.

 

The appropriate model depends on the contractor's measurement, logging and connectivity requirements.

 

Who Should Consider a WBGT Meter?

 

Potential users include:

 

Solar EPC contractors

 

Rooftop solar installers

 

Solar farm operators

 

Solar O&M companies

 

Safety and Health Officers

 

EHS / HSE teams

 

Electrical contractors

 

Facility managers

 

Renewable energy consultants

 

Utility contractors

 

Building a Solar Safety & Testing Instrument Kit

 

For solar contractors, WBGT can also complement existing testing equipment.

 

A practical instrument range may include:

 

Heat Stress: WBGT Meter

 

Solar Performance: Solar Irradiance Meter

 

Electrical: Multimeter / Clamp Meter

 

PV Testing: Solar / PV Tester

 

Temperature: Infrared Thermometer

 

Thermal Inspection: Thermal Imager

 

This gives contractors tools for both worker safety and photovoltaic system testing.

 

Tenmars WBGT Meter Supplier for Solar Industry Malaysia

 

MTM Precision supplies professional Tenmars Heat Stress WBGT Meters and solar testing instruments in Malaysia.

 

We support applications involving:

 

Rooftop Solar • Solar Farm • Solar EPC • O&M • Electrical Contractors • EHS • HSE • Occupational Safety • PV Testing

 

Contact our team with your application and measurement requirements for assistance selecting suitable instruments.

 

MTM Precision Sdn Bhd

 

Website: www.mtmpre.com.my

WhatsApp: +6016-660 7346

Email: mtmpre@yahoo.com

 

Showroom & Service Centre

 

No. 29-1 & 29-2, Jalan Bandar 18,

Pusat Bandar Puchong,

47160 Puchong, Selangor, Malaysia.

 

Looking for a WBGT Heat Stress Meter for rooftop or solar farm workers in Malaysia? Contact MTM Precision for Tenmars WBGT Meter selection and quotation.