Risk Assessment: Under Pressure Drilling and Tapping Operations¶
Document Information
| Field | Value |
|---|---|
| Document Reference | RA19 |
| Issue Number | 2 |
| Issue Date | 1 June 2026 |
| Next Review | 1 June 2027 |
| Prepared By | Sean Ashton |
| Approved By | Aaron Mason, Director |
Risk Assessment Table¶
| Activity/Process | Hazard | Who/What Affected | Existing Controls | Pre-Control Risk (S/L/R) | New Controls Required | Post-Control Risk (S/L/R) |
|---|---|---|---|---|---|---|
| Identifying the correct main to be drilled | Drilling incorrect main leading to contamination or release of gas/sewage | Public water supply, operatives, members of public | • Main positively identified by Client before work • Up-to-date utility drawings checked • Visual inspection of valves/stop taps • Pipe sounding to confirm water network • CAT and Genny used for identification • Pressure testing where appropriate |
5/3/15 (High) | • Implement mandatory 'positive identification' protocol with multiple confirmation methods • Develop standardised pipe identification checklist • Provide enhanced training on pipe identification SLT/HSQE, immediate |
5/2/10 (High) |
| Preparation for under pressure drilling | Inadequate preparation leading to equipment failure or loss of pressure control | Operatives, members of public, property | • Equipment inspected before use • Appropriate drilling machines selected • Pressure ratings checked against system • Work area isolated from public • Fittings disinfected with chlorine solution • PPE provided (eye protection, gloves, safety footwear) • Adequate working space established |
4/3/12 (High) | • Develop pre-drilling equipment checklist • Enhanced training on pressure control and emergency procedures • Mandate second competent person for high-pressure operations (>3 bar) HSQE, within 1 month |
4/2/8 (Moderate) |
| Drilling and tapping cast iron, ductile, steel, or PE mains | High-pressure water release, sudden ejection of equipment | Operatives - injuries from water release or tool failure | • Only trained personnel undertake operations • Equipment correctly assembled and secured • Pressure controlled throughout drilling • PPE worn (EN 166 1B349 eye protection, cut-resistant gloves) • Appropriate drilling rate to prevent breakthrough • Equipment follows manufacturer's guidelines |
4/3/12 (High) | • Implement formal competence verification system • Additional practical training on drilling technique HSQE, ongoing |
4/2/8 (Moderate) |
| Drilling and tapping asbestos cement pipelines | Release of asbestos fibers during drilling | Operatives - respiratory conditions (asbestosis, lung cancer, mesothelioma) | • Manual drilling machines for asbestos cement • Operatives have Category B training (within 12 months) • RPE worn (minimum FFP3) • Pipe kept wet during drilling • Work area segregated • Disposable coveralls worn and disposed as asbestos waste • Decontamination facilities provided |
5/3/15 (High) | • Develop specific procedures for asbestos cement pipes • Provide powered respirators for asbestos drilling • Implement air monitoring during operations Sean Ashton / Directors, immediate |
5/2/10 (High) |
| Fitting and using drilling machines | Mechanical injury from moving parts, equipment failure under pressure | Operatives - crush injuries, lacerations, impact injuries | • Personnel trained in manual and electric drilling machines • Equipment inspected for defects • Guards in place on moving parts • Correct cutting tools for pipe material • Machines properly secured before operation • Components disinfected before use • Operated per manufacturer's instructions |
4/3/12 (High) | • Implement formal equipment inspection protocol • Enhanced training on machine assembly • Second person verification before drilling Sean Ashton / Site Supervisors, immediate |
4/2/8 (Moderate) |
| Disinfection and lubrication of components | Chemical exposure, contamination of water supply | Operatives - chemical burns/irritation, public water contamination | • COSHH assessments provided • PPE provided (chemical-resistant gloves, EN 166 1B349 eye protection) • Only approved disinfection solutions and food-grade lubricants • Components thoroughly disinfected • Hand washing facilities and eye wash available • Chemicals correctly labeled and stored • Personnel trained in safe handling |
3/3/9 (Moderate) | • Develop standardised disinfection protocol with visual guides • Verification system for approved chemicals • Enhanced training on contamination consequences HSQE, within 1 month |
3/2/6 (Moderate) |
| Operating electric or pneumatic drilling equipment | Electric shock, noise exposure, hand-arm vibration | Operatives - electric shock, hearing damage, HAVS | • All electrical equipment 110V or RCD protected • Equipment inspected for cable damage • Hearing protection provided and worn • Vibration monitored through job rotation • Regular maintenance to minimise vibration/noise • Pneumatic equipment checked for leaks • Personnel trained in correct use |
4/3/12 (High) | • Formal electrical inspection system with documentation • Enhanced anti-vibration gloves • Vibration exposure monitoring system • Consider lower vibration equipment Sean Ashton / Directors, ongoing |
4/2/8 (Moderate) |
| Completion of drilling and tapping operations | Uncontrolled water release when removing equipment, inadequate sealing | Operatives - injuries from water release, public water contamination, property damage | • Equipment removed following procedures to maintain pressure • Connections properly sealed before equipment removal • Visual inspection for leaks after completion • Pressure testing where required • Only approved fittings and sealing materials • Site not left until connection confirmed secure • Personnel trained in emergency procedures |
4/3/12 (High) | • Develop formal completion checklist • Mandatory waiting period after connection • Enhanced training on sealing techniques HSQE, immediate |
4/2/8 (Moderate) |
Key:¶
- S = Severity (1-5 scale)
- L = Likelihood (1-5 scale)
- R = Risk Rating (S × L)
- Risk Levels:
- Low (1-3)
- Moderate (4-8)
- High (9-15)
- Very High (16-25)
Related Documents¶
- EN 166 1B349: Eye Protection Standard
- Category B Non-Licensed Asbestos Training Requirements
- UN3291 and BS7320: Sharps Container Standards