HTM 02-01:2026 Clause 1.31 Designers Must Demonstrate Competence in MGPS Design

 HTM 02-01:2026 Clause 1.31 Designers Must Demonstrate Competence in MGPS Design

HTM 02-01, Medical Gas Pipeline Systems (MGPS) was published on 19 August 2026. Part A covers the design, installation, validation and verification of medical gas pipeline systems. 

One particularly important point for consulting engineers, MEP engineers and MGPS specialists is Clause 1.31, which explicitly includes the training and competency of designers and contractors, alongside Authorized Persons (MGPS) and Authorizing Engineers (MGPS). 

What does Clause 1.31 mean?

The practical message is straightforward:

Being an experienced mechanical or MEP engineer alone is not sufficient evidence that someone is competent to design an MGPS.

Medical gas systems are safety-critical healthcare infrastructure. The designer needs appropriate skills, knowledge, experience and behaviors for the work they undertake not simply the ability to follow a drawing, spreadsheet, specification or calculation procedure. 

This matters because an MGPS design error can affect oxygen, medical air, vacuum and other clinical services used directly for patient care.

What should an MGPS designer be competent in?

A designer should be capable of developing and checking the system from the clinical demand through to the source plant and distribution network. In practical terms, competence should cover areas such as:

1. Clinical demand and terminal-unit provision

The designer needs to understand where terminal units are required and the clinical requirements of different departments—for example:

• Operating theatres
• ICU/HDU
• Emergency departments
• Recovery
• Wards
• NICU
• Imaging and diagnostic areas
• Treatment rooms

The design cannot simply assume that every terminal unit operates simultaneously at maximum flow.

2. Diversified-flow calculations

One of the most important MGPS design skills is determining the appropriate design flow.

The designer needs to understand:

• Number of terminal units 
• Department demand 
• Diversity 
• Simultaneous demand
•  Pipeline design flow

Incorrect diversity assumptions can result in either an undersized system that cannot maintain clinical demand or an unnecessarily oversized and expensive installation.

3. Pipeline sizing and pressure-loss calculations

Once design flow is established, the designer needs to determine suitable pipe sizes while maintaining the required pressure and flow at the point of use.

Conceptually:

Source pressure − Pipeline losses − Fitting/valve losses = Available terminal pressure

This requires understanding the effects of:

• Pipe diameter
• Pipe length
• Gas flow
• Fittings
• Valves
• Elevation where relevant
• Simultaneous demand
• Required terminal pressure
• Permissible pressure drop

A software result alone should not substitute for engineering understanding.

4. Source and plant capacity

The designer also needs to establish appropriate source capacity and resilience.

Depending on the service, this can include:

• PSA oxygen generators
• Liquid oxygen/VIE systems
• Cylinder manifolds
• Medical-air compressor plants
• Surgical-air systems
• Medical vacuum plants
• Emergency/reserve supplies

The design must consider normal demand, peak demand, standby capacity, maintenance conditions and failure scenarios.

5. AVSUs, LVAs and alarms

Competence extends beyond piping.

The designer must understand appropriate provision and positioning of:

AVSU — Area Valve Service Unit

Allows a defined clinical area to be isolated.

LVA — Line Valve Assembly

Provides isolation of appropriate sections of the distribution system.

Alarm systems

The designer needs to understand local, plant and central alarm requirements so abnormal pressure, plant failure or supply conditions can be identified promptly.

6. System resilience

Healthcare MGPS design should consider what happens when something fails.

For example:

Normal Source → Standby Source → Emergency/Reserve Supply

The designer should consider credible conditions such as:

• One compressor unavailable
• One vacuum pump unavailable
• Oxygen source failure
• Power failure
• Maintenance isolation
• Pipeline isolation
• Abnormal peak demand
• Plant-room equipment failure

The objective is not simply to satisfy normal operating demand, but to provide the required continuity and resilience for patient care.

How can designers demonstrate competence?

Clause 1.31 should not be interpreted as meaning that possession of one particular certificate automatically proves competence. Competence is broader than certification.

Evidence may include a combination of:

• Relevant engineering education
• Specialist MGPS design training
• Knowledge of current HTM 02-01 requirements
• Practical MGPS design experience
• Diversified-flow calculations
• Pipeline sizing and pressure-loss calculations
• Source-plant sizing experience
• Completed MGPS projects
• Design reviews and checking
• Continuing professional development
• Assessments or recognized training certificates
• Evidence of understanding clinical risk and system resilience

Specialist training remains particularly relevant. For example, IHEEM's MGPS training describes detailed understanding of HTM 02-01, system design and operation, schematic diagrams, maintenance/testing and safety responsibilities as core learning areas. IHEEM

What should organizations request from MGPS designers?

For future healthcare projects, a useful competence-assurance process would be to obtain evidence covering:

Qualifications → MGPS training → Relevant experience → Example designs/calculations → Knowledge of current HTM → Competence assessment → Appointment/approval

This makes competence auditable rather than assumed.

A designer competency matrix can therefore become an important project document.

Competency Area Evidence HTM 02-01 knowledge Current training/assessment Clinical gas requirements Project experience Terminal-unit scheduling Design records Diversified-flow calculation Calculation sheets Pipeline sizing Hydraulic calculations Pressure-loss calculation Design calculations/software outputs Source sizing Plant-selection calculations AVSU/LVA design Drawings/schedules Alarm philosophy Schematics/cause-and-effect Resilience Design-risk assessment Practical MGPS experience Project portfolio Continuing competence CPD/training records

Why this matters for MEP engineers

The important change is cultural as much as technical:

Old approach:
Experienced engineer → produces MGPS design → competence largely assumed.

Stronger assurance approach:
Designer 

• Demonstrates relevant MGPS competence 
• Calculations and design decisions are traceable
• Independent review/verification 
• Documented evidence retained.

This creates a clearer line of accountability:

• Clinical Requirements
•  Competent Designer 
• Compliant Design
•  Correct Installation 
• Validation/Verification 
•  Safe MGPS Operation

The previous HTM framework already emphasized that medical gas systems are specialized services requiring significant expertise and that personnel involved should be able to demonstrate competence to clients. The 2026 edition's explicit reference to designers in Clause 1.31 reinforces that expectation. 

Key message

MGPS design competence should be demonstrated, documented and maintained not assumed from job title or general MEP experience.

For hospitals, consultants and contractors, this means greater attention to the competency of the individual actually performing diversity calculations, pipeline sizing, source selection, pressure-loss calculations, zoning, alarms and resilience design.