High-Rise Building Window Glass Cleaning Using a Building Maintenance Unit (BMU)

Assessment Date: [DATE]

Assessor: [ASSESSOR NAME]

Department/Area: [DEPARTMENT/AREA]

Review Date: [REVIEW DATE]

1. Assessment Scope

This risk assessment covers planned window glass cleaning operations on the exterior of a high-rise building using a Building Maintenance Unit (BMU), including access to the roof or BMU operating area, setup and use of suspended access equipment, cleaning activities at height, movement along the façade, and demobilization after work completion. It includes hazards associated with falls from height, suspension in a harness, dropped objects, equipment failure, weather and wind exposure, and emergency rescue from suspended access systems. The assessment applies to employees, supervisors, competent persons, rescue personnel, and any other persons who may be exposed to the work area or drop zones. It excludes structural repairs, façade replacement, major BMU installation or modification, and any work requiring specialist engineering beyond routine cleaning operations unless separately assessed and authorized.

2. Risk Assessment Methodology

This assessment uses a structured hazard identification and risk evaluation process based on a 5x5 matrix approach. Hazards are identified for each stage of the task, the initial risk is rated using likelihood and severity, and controls are selected using the hierarchy of controls: elimination, substitution, engineering controls, administrative controls, and PPE. Residual risk is then reassessed after controls are applied. The assessment also incorporates permit-to-work requirements, pre-use inspection, competent person oversight, rescue planning, and ongoing monitoring to ensure controls remain effective throughout the task.

3. Risk Matrix Reference

The following matrix is used to evaluate risk levels based on likelihood and severity:

		Likelihood
Rare	Unlikely	Possible	Likely	Almost Certain
Severity	Catastrophic	Low	Low	Low	Low	Medium
Major	Low	Low	Medium	Medium	High
Moderate	Low	Medium	Medium	High	High
Minor	Medium	Medium	High	High	Extreme
Negligible	Medium	High	High	Extreme	Extreme

4. Hazard Identification and Risk Evaluation

1. Fall from height while accessing, boarding, operating, or exiting the BMU platform or suspended work position.

Potential Consequences: A fall could result in fatal injuries, major trauma, fractures, spinal injury, or permanent disability. A fall while suspended may also lead to suspension trauma if rescue is delayed. [1] [1]

Affected Persons: BMU operators, window cleaners, supervisors assisting with setup, and rescue personnel.

Initial Risk Assessment

Likelihood	Severity	Risk Rating
Possible	Catastrophic	Extreme

Control Measures

• Eliminate unnecessary exposure by planning work so access routes, tie-off points, and cleaning sequences minimize time at the edge.
• Use a BMU and access system designed for the task and approved for the building, with independent fall arrest protection where required.
• Provide engineering controls such as compliant anchorages, lifelines, guardrails, interlocks, and secure access/egress arrangements.
• Implement a permit-to-work system, pre-task briefing, competent person oversight, and a written work plan reviewed with workers and building management.
• Require full-body harnesses, compatible connectors, and fall arrest equipment worn and connected as required before approaching the point of suspension.

Residual Risk Assessment

Likelihood	Severity	Risk Rating
Unlikely	Catastrophic	High

2. Failure, misuse, or incompatibility of suspended access equipment, including BMU components, connectors, lifelines, anchorages, or fall arrest devices.

Potential Consequences: Equipment failure may cause a fall, uncontrolled descent, platform instability, or inability to complete a rescue. Incompatible connectors may disengage or reduce system strength. [1] [3]

Affected Persons: Window cleaners, BMU operators, maintenance staff, and rescuers.

Initial Risk Assessment

Likelihood	Severity	Risk Rating
Possible	Catastrophic	Extreme

Control Measures

• Eliminate use of defective, modified, or non-approved equipment from service immediately.
• Use only equipment designed for window cleaning and suspended access, with components compatible with the full system.
• Apply engineering controls through certified anchorages, independent fall arrest anchorage, and manufacturer-approved BMU interfaces.
• Require pre-use inspection, scheduled maintenance, and inspection by a competent person before each shift and after any event that may affect integrity.
• Prohibit unsafe or non-compliant equipment such as portable sills, window jacks, capstan devices, and non-compliant polypropylene ropes.

Residual Risk Assessment

Likelihood	Severity	Risk Rating
Rare	Catastrophic	High

3. Dropped objects from tools, cleaning equipment, debris, or materials falling from the BMU platform or façade.

Potential Consequences: Dropped objects can strike workers below, pedestrians, vehicles, or property, causing serious injury, fatality, or damage to glass and building surfaces. [2] [9]

Affected Persons: Workers on lower levels, pedestrians, occupants, visitors, traffic, and the public.

Initial Risk Assessment

Likelihood	Severity	Risk Rating
Likely	Major	Extreme

Control Measures

• Eliminate loose items at height by using only essential tools and materials.
• Use engineering controls such as tool lanyards, secured buckets, toe boards where applicable, debris containment, and exclusion zones below the work area.
• Establish drop zones and barricade them with clear signage and access control.
• Use administrative controls including tool accountability, housekeeping checks, and controlled transfer of materials to and from the platform.
• Require PPE including hard hats, safety footwear, and eye protection for exposed workers and any authorized persons in the area.

Residual Risk Assessment

Likelihood	Severity	Risk Rating
Unlikely	Major	High

4. Adverse weather and wind affecting BMU stability, worker balance, visibility, and control of tools or suspended equipment.

Potential Consequences: High winds, rain, ice, lightning, or poor visibility may cause loss of balance, collision with the façade, dropped objects, equipment swing, or inability to conduct a safe rescue. [9] [7]

Affected Persons: Window cleaners, BMU operators, rescue personnel, and persons below the work area.

Initial Risk Assessment

Likelihood	Severity	Risk Rating
Likely	Major	Extreme

Control Measures

• Eliminate work during unsafe weather conditions by stopping operations when wind or weather exceeds site limits or manufacturer limits.
• Use engineering controls such as anemometers or wind monitoring devices and secure stowage for the BMU when not in use.
• Set administrative stop-work criteria for wind, lightning, rain, ice, fog, and extreme temperatures, with authority for workers and supervisors to suspend work.
• Review weather forecasts before work and continuously monitor conditions during the shift.
• Provide suitable PPE for weather exposure, including gloves, eye protection, and thermal or rain protection where appropriate.

Residual Risk Assessment

Likelihood	Severity	Risk Rating
Unlikely	Major	High

5. Inadequate operator competency, supervision, or training for BMU operation, suspended access, and rescue response.

Potential Consequences: Incorrect operation may lead to collision, overloading, improper tie-off, delayed rescue, equipment damage, or unsafe emergency response. [2]

Affected Persons: BMU operators, window cleaners, supervisors, rescue personnel, and others relying on the system.

Initial Risk Assessment

Likelihood	Severity	Risk Rating
Possible	Major	High

Control Measures

• Eliminate untrained personnel from operating or supervising the BMU.
• Use only competent and authorized operators, with qualified oversight for complex tasks and rescue planning.
• Provide task-specific training on BMU operation, fall protection, rescue procedures, communication, and emergency shutdown.
• Use written procedures, pre-job briefings, and supervision to verify understanding before work begins.
• Maintain records of competency, refresher training, and authorization status.

Residual Risk Assessment

Likelihood	Severity	Risk Rating
Rare	Major	Medium

6. Failure to use or correctly wear fall arrest and fall prevention systems, including harnesses, lanyards, lifelines, and anchorage connections.

Potential Consequences: A worker may fall from height, suffer suspension trauma, or be unable to self-rescue. Incorrect fit or connection may increase injury severity. [1] [3]

Affected Persons: Window cleaners and any worker exposed to the edge or suspended position.

Initial Risk Assessment

Likelihood	Severity	Risk Rating
Possible	Catastrophic	Extreme

Control Measures

• Eliminate exposure where travel restraint or guardrail protection can prevent approach to the edge.
• Use engineering controls such as independent fall arrest anchorage and compatible connectors.
• Require full-body harnesses and compatible fall arrest systems to be assembled and worn before approaching the point of suspension.
• Implement administrative checks for correct fit, connection, and continuous attachment while suspended.
• Provide PPE inspection before each use and remove damaged equipment from service immediately.

Residual Risk Assessment

Likelihood	Severity	Risk Rating
Unlikely	Catastrophic	High

7. Emergency rescue delay following a fall, medical event, or equipment malfunction while a worker is suspended.

Potential Consequences: Delayed rescue can cause suspension trauma, worsening injury, loss of consciousness, organ damage, or death. Rescue attempts may also expose rescuers to the same hazards. [4] [6]

Affected Persons: Suspended workers, rescue personnel, and supervisors coordinating the response.

Initial Risk Assessment

Likelihood	Severity	Risk Rating
Possible	Catastrophic	Extreme

Control Measures

• Eliminate reliance on emergency services alone by establishing a site-specific rescue plan before work begins.
• Use engineering and administrative controls to ensure rescue equipment, access routes, and communication systems are immediately available.
• Assign trained rescue personnel with defined roles and responsibilities and conduct rescue drills before the task starts.
• Include self-rescue, assisted rescue, and retrieval methods appropriate to the BMU and building layout.
• Maintain first aid supplies, communication backup, and a clear route for medical transfer if required.

Residual Risk Assessment

Likelihood	Severity	Risk Rating
Unlikely	Major	High

8. Sharp edges, façade projections, window frames, ledges, cornices, or overhangs damaging ropes, lifelines, or other suspension components.

Potential Consequences: Abrasion, cutting, or failure of ropes and lifelines may lead to loss of support, fall arrest failure, or sudden descent. [2]

Affected Persons: Window cleaners, BMU operators, and rescue personnel.

Initial Risk Assessment

Likelihood	Severity	Risk Rating
Possible	Catastrophic	Extreme

Control Measures

• Eliminate contact with sharp edges where possible by adjusting access position or work sequence.
• Use engineering controls such as edge protection, padding, and rope protection devices secured against dislodgement.
• Inspect the building exterior before use to identify hazardous edges and protrusions.
• Use administrative controls to define safe travel paths and prohibit movement across unprotected edges.
• Require PPE and equipment compatible with the work environment, with damaged ropes or connectors removed from service.

Residual Risk Assessment

Likelihood	Severity	Risk Rating
Rare	Major	Medium

9. Slips, trips, and manual handling injuries during preparation, cleaning, and demobilization on the roof or BMU access area.

Potential Consequences: Workers may suffer sprains, strains, falls, or impact injuries, and may drop tools or lose control of equipment. [8]

Affected Persons: Window cleaners, BMU operators, supervisors, and maintenance staff.

Initial Risk Assessment

Likelihood	Severity	Risk Rating
Likely	Moderate	High

Control Measures

• Eliminate unnecessary materials and keep access routes clear.
• Use engineering controls such as non-slip surfaces, secure storage for tools, and adequate lighting where needed.
• Apply housekeeping and manual handling procedures to keep walkways dry, clear, and unobstructed.
• Use team lifting or mechanical aids for heavy items and limit carrying loads while moving near edges.
• Require suitable footwear with slip-resistant soles and gloves for handling equipment.

Residual Risk Assessment

Likelihood	Severity	Risk Rating
Unlikely	Minor	Low

5. General Control Measures

• Implement a permit-to-work system for all BMU window cleaning activities.

The permit should confirm that the work area has been inspected, weather limits are acceptable, rescue arrangements are in place, equipment is inspected, and only authorized personnel are permitted to proceed.

• Conduct a pre-task briefing and written work plan before each shift.

The briefing should cover the work sequence, drop zones, communication methods, emergency actions, stop-work authority, and any building-specific hazards. [2]

• Restrict access to the work area and establish exclusion zones below suspended operations.

Use barriers, signage, and access control to protect workers, occupants, visitors, and the public from dropped objects and falling debris.

• Ensure all BMU and fall protection equipment is inspected, maintained, and removed from service if defective.

Use pre-use checks, scheduled maintenance, and competent person inspections. Record defects, repairs, and authorization to return equipment to service. [10]

• Maintain clear communication and supervision throughout the task.

Use radios or another reliable communication method, confirm backup communication, and ensure the supervisor can stop work immediately if conditions change. [11]

6. Emergency Preparedness

• A site-specific rescue plan shall be written, reviewed, and briefed before work begins. The plan must address suspension rescue, self-rescue, assisted rescue, medical emergencies, and equipment failure scenarios, and must not rely solely on calling external emergency services. [4]
• Rescue equipment, first aid supplies, and communication devices shall be staged and immediately available at the worksite. Equipment must be suitable for the BMU configuration and the building geometry, and must be inspected before use. [5]
• Rescue personnel shall be assigned in advance with clear roles for initiating rescue, contacting emergency services, controlling the area, and providing first aid. All workers must know how to raise the alarm and who has authority to stop the job. [4]
• Emergency procedures shall include rapid retrieval of a suspended worker to prevent suspension trauma, with priority given to minimizing time in harness and transferring the worker to medical care if needed. [4]
• The rescue plan shall identify access routes, roof exits, the quickest route to hospital, and any site-specific constraints such as restricted access, weather exposure, or ground-level obstructions. [6]

7. Training Requirements

• BMU Operator Competency Training: Operators shall be trained and authorized to operate the specific BMU model and associated controls. Training must cover safe start-up and shutdown, movement and positioning, load limits, emergency stop functions, communication, and recognition of abnormal conditions requiring work stoppage. [2]
  • Pre-use checks and defect reporting
  • Safe operation near the façade and roof edge
  • Emergency lowering or shutdown procedures
  • Manufacturer instructions and site rules
• Fall Protection and Harness Use Training: Workers shall be trained in the correct selection, fitting, inspection, use, and limitations of full-body harnesses, lanyards, lifelines, connectors, and anchorage systems. Training must emphasize continuous connection where required and the need to assemble and wear fall arrest equipment before approaching the point of suspension. [1] [1]
  • Harness inspection before each use
  • Correct adjustment of chest and leg straps
  • Compatibility of connectors and anchorage points
  • Removal from service of damaged equipment
• Rescue and Suspension Trauma Awareness Training: All workers and designated rescuers shall be trained on rescue initiation, suspension trauma hazards, self-rescue where applicable, assisted rescue methods, and first aid actions following a fall or medical emergency. Training should include drills and simulated rescues so the team can respond quickly and safely. [4] [11]
  • Recognizing signs of suspension trauma
  • Communication and alarm procedures
  • Use of rescue equipment and retrieval methods
  • First aid and CPR for designated rescuers
• Dropped Object Prevention and Exclusion Zone Training: Workers shall be trained to secure tools, manage materials, maintain housekeeping, and respect exclusion zones below suspended work. Training must cover tool tethering, controlled transfer of equipment, and the prohibition on dropping or throwing items from height. [2]
  • Tool lanyards and secured containers
  • Barricading and signage
  • Housekeeping and material control
  • Public protection measures
• Weather and Stop-Work Criteria Training: Workers shall be trained to recognize unsafe weather conditions, including high winds, rain, ice, lightning, poor visibility, and extreme temperatures, and to stop work when conditions exceed site or manufacturer limits. Training must include the authority to suspend operations without delay. [9] [7]
  • Wind monitoring and thresholds
  • Weather forecast review
  • Cold, heat, rain, and lightning precautions
  • Stop-work authority

8. Monitoring and Review

Review Frequency: Annually, and after any incident, near miss, equipment failure, rescue event, significant weather event, or change to the BMU system, building façade, work method, or rescue arrangement.

Monitoring Type	Frequency	Responsible Party	Description
Regular Inspection	Before each use and at the start of each shift	BMU operator and competent person	Inspect the BMU, suspension components, connectors, lifelines, harnesses, anchorages, and tool tethering arrangements for damage, wear, compatibility, and correct assembly. Remove defective equipment from service immediately.
Weather Monitoring	Continuously during operations, with formal checks before work begins and after any weather change	Supervisor or designated competent person	Monitor wind speed, precipitation, lightning risk, visibility, and temperature. Stop work when conditions exceed safe limits or when the building façade becomes slippery or unstable.
Work Area and Drop Zone Inspection	Before work begins and periodically during the shift	Supervisor	Verify that exclusion zones remain intact, access routes are clear, tools are secured, and no unauthorized persons have entered the hazard area below the work face.
Rescue Readiness Check	Before each job and during drills at planned intervals	Rescue team leader or qualified rescue supervisor	Confirm that rescue equipment, communication devices, first aid supplies, and access routes are available, functional, and appropriate for the specific BMU and building configuration.
Competency and Authorization Review	At induction, after retraining, and at least annually	Employer or safety manager	Verify that operators, cleaners, and rescuers remain competent, current, and authorized for the task. Review training records, drill participation, and any restrictions on work at height.

9. Special Circumstances

• High winds, storms, lightning, rain, ice, or extreme temperatures may require immediate suspension of work and additional controls for equipment stability, visibility, and worker exposure.
• Night work or low-light conditions increase the risk of miscommunication, dropped objects, and incorrect connection of fall protection equipment. Additional lighting and supervision are required.
• Lone work is not permitted for suspended window cleaning or rescue-critical tasks because immediate assistance may be required in the event of a fall, medical emergency, or equipment malfunction.
• Work near public areas, traffic, or occupied lower levels requires enhanced exclusion zones, signage, and coordination with building management to protect third parties.
• Cold weather, heat stress, or poor visibility can reduce dexterity, concentration, and rescue effectiveness, and must be considered in the permit-to-work and rescue planning process.

Approval and Sign-off

This risk assessment has been reviewed and approved by:

Assessor: _________________________ Date: __________

Manager/Supervisor: _________________________ Date: __________

Safety Representative: _________________________ Date: __________

This risk assessment must be reviewed annually, and after any incident, near miss, equipment failure, rescue event, significant weather event, or change to the bmu system, building façade, work method, or rescue arrangement. or when significant changes occur.

Safety powered by SALUS