VIENID Start practicing

Home › Lessons › Construction – Building (SSW 2)

Foreman Safety & Health Activities and Risk Management

Construction – Building (SSW 2) · 建設分野(2号・建築区分) · Written by Tokutei Pass based on the official study texts; not copied verbatim.

Foreman Safety Training (Article 60) and Risk Assessment

Statutory items in 'Foreman Safety and Health Training' under Article 60 of the Industrial Safety and Health Act include determining work methods and worker placement, supervision/guidance methods, risk assessment, and abnormality/accident response (construction business license applications and management evaluations are NOT included).

Conduct 'Risk Assessment' when formulating work plans or when newly adopting or changing machinery, materials, or work procedures.

Estimate the magnitude (priority) of each identified hazard's risk by combining two elements: the 'probability (frequency) of accident occurrence' and the 'severity of injury or illness (Juutokudo)'.

When planning risk reduction measures while ensuring legal compliance, the 1st priority (highest priority) is '1. Intrinsic/Essential measures (eliminating hazardous work or substituting less hazardous materials)', followed by engineering controls, administrative controls, and personal protective equipment (PPE).

Foreman Safety Training (Article 60) and Risk Assessment

Key points


  • Statutory Foreman Training does NOT include construction business licensing or management review procedures.

  • Risk magnitude is estimated by combining 'occurrence probability (frequency)' and 'severity of injury (Juutokudo)'.

  • The 1st priority in risk reduction is 'intrinsic measures' such as eliminating hazardous tasks or substituting safer materials.
WordMeaning
Risk Assessment
Severity of injury or illness (Juutokudo)
Intrinsic / Essential safety measures (Honshitsuteki taisaku)

Heinrich's Law, KYT Basic 4-Round Method, and Why-Why Analysis

The safety principle stating that behind 1 major accident lie 29 minor accidents and 300 near-misses (Hiyari-Hatto) is called 'Heinrich's Law (1 : 29 : 300 ratio)'.

Occupational accidents usually occur when physical/environmental 'unsafe conditions (e.g., a broken and detached safety guard on a circular saw)' overlap with human 'unsafe acts'.

The 'KYT Basic 4-Round Method' proceeds in order: '1R: Grasp current status → 2R: Pursue essence → 3R: Establish countermeasures → 4R: Set action goals', and 'pointing-and-calling (Shisa koshou)' raises awareness to reduce human error.

When investigating accidents or near-misses to prevent recurrence, do not stop at individual error—use 'Why-Why Analysis (Naze-naze bunseki)' to uncover root indirect causes in equipment defects, management, and training.

Key points


  • The 1 : 29 : 300 ratio among major accidents, minor accidents, and near-misses is 'Heinrich's Law'.

  • A broken or missing circular saw blade guard is classified as an environmental/mechanical 'unsafe condition'.

  • The KYT 4-Round Method follows: 1R Grasp status → 2R Pursue essence → 3R Establish countermeasures → 4R Set goals.
WordMeaning
Heinrich's Law (1 : 29 : 300)
KYT Basic 4-Round Method
Why-Why Analysis (Naze-naze bunseki)

Accident Statistics (Frequency & Severity Rates), 5S, SDS, and Emergencies

The number of casualties per 1,000,000 working hours is the 'frequency rate (Dosuuritsu)'; 2 casualties in 500,000 hours gives a frequency rate of 2 ÷ 500,000 × 1,000,000 = 4.0. The number of lost workdays per 1,000 working hours is the 'severity rate (Kyoudoritsu)', indicating accident severity.

In 5S activities: 'Seiri (Sort)' means discarding unneeded items, 'Seiton (Set in order)' means placing needed items for easy retrieval, 'Seiketsu (Standardize)' means maintaining the state of Seiri, Seiton, and Seisou, and 'Shitsuke (Sustain)' means building the habit of following rules.

Before handling paints or adhesives containing chemicals, check the 'SDS (Safety Data Sheet)' for hazard information, handling precautions, first-aid measures, and storage instructions.

If abnormal machine noise or loose scaffold parts are found, stop the machine/work first and report to a supervisor; in a major accident, stop work immediately to prevent secondary accidents, rescue the injured, and make an emergency report to the prime contractor.

Key points


  • 2 casualties in 500,000 working hours equals a frequency rate of '4.0'; lost workdays per 1,000 hours is the 'severity rate'.

  • In 5S, discarding unneeded items is 'Seiri', maintaining 3S is 'Seiketsu', and habituating rule compliance is 'Shitsuke'.

  • Check the 'SDS' before using chemicals, and stop work immediately during abnormalities or accidents to prevent secondary disasters.
WordMeaning
Frequency rate (Dosuuritsu) & Severity rate (Kyoudoritsu)
Safety Data Sheet (SDS)
Heatstroke prevention (Simultaneous water & salt intake)

Scaffold Inspections, Guardrail Standards, PPE, Health & Older Workers

Inspect scaffolds before starting work after 'strong winds, heavy rain, or heavy snow' and after 'earthquakes of seismic intensity 4 (medium earthquake) or higher'. Fall prevention equipment on working floors requires a 'top guardrail at least 85 cm high and a mid-rail (Nakazan) 35 cm to 50 cm high'.

Use a full-body harness with a 'double lanyard (2-chougake)' so one hook remains attached while moving, and hook onto a lifeline above waist level. Replace any safety helmet that has suffered a strong impact even if no cracks are visible.

During morning assemblies and KY activities, check workers' complexion, sleep deprivation, and health, and reassign unwell workers away from high-place or hazardous tasks. The manual lifting guideline (approx. 40% or less of body weight) for a 60 kg adult male is 'approx. 24 kg or less'.

Because older workers are prone to declining vision and balance, provide adequate walkway lighting and eliminate floor level steps.

Key points


  • Inspect scaffolds before work after severe weather or earthquakes of seismic intensity 4 or higher.

  • Scaffold top rails must be ≥ 85 cm high and mid-rails 35–50 cm high; use a double-lanyard full-body harness hooked above waist level.

  • Manual lifting for a 60 kg male should be 'approx. 24 kg or less' (≤ 40% of body weight); ensure lighting and step-free walkways for older workers.
WordMeaning
Double lanyard (2-chougake)
Scaffold mid-rail (Nakazan)
5S Activities (Sort, Set in order, Shine, Standardize, Sustain)

Foreman Safety and Health Activities

Practice this chapter in the app

Official references