MEDICAL GAS SAFETY PSV PSV
Primary control panel
G
Primary LOX Tank
PSV evaporators Assembly Line Valve Valve Line NC
Return valave
Non
Line Valve Line
Inside the curtilage of the building Line
Assembly Valve Main PSV Regulator G PSV Regulator Lag PSV P Lead
G
PSV
P Assembly Valve Line
Assembly
Valve
Pipeline System
Main LOX Supply on external plinth
Secondary Automatic Manifold Supply
To
xxxxxxxx
Primary, secondary, and tertiary: resilience beyond standby plant Part A also strengthens how resilience is addressed through primary, secondary, and tertiary supplies. This terminology moves the discussion beyond the assumption that resilience is achieved simply by installing duty and standby plant. The more important question is what supply remains available if the normal source, or the route from that source, is compromised. The primary supply supports normal operation. The secondary arrangement provides continuity following the relevant failure scenario. Tertiary provision adds a further layer, determined through the IDP and the clinical risk. Depending on the system and application, that could involve a further fixed pipeline source, a portable manifold, or individual cylinders. The exact arrangement is less important than the principle: the organisation should know how essential patients will continue to receive gas if the first layers of resilience are unavailable. Tertiary supply therefore connects engineering design
directly with emergency and clinical contingency planning. It needs sufficient capacity for the intended scenario, a practical method of deployment or changeover, trained staff, appropriate connections, and a clear understanding of which clinical services are prioritised. A tertiary source that exists on a drawing but cannot be deployed safely or quickly is not meaningful resilience. This is particularly relevant to oxygen. COVID-19
showed that a hospital can have adequate bulk storage while still encountering delivery constraints. Resilience must be considered along the entire chain: storage, evaporators, pressure regulation, distribution mains, risers, branches, area valves, terminal units, and the patient interface. Primary, secondary, and tertiary supplies add protection, but the distribution network must still be capable of carrying the required flow.
Validation and verification: prove the system before it is released for use One of the most important improvements in Part A is the
greater prominence given to validation and verification. This matters because an MGPS can appear complete while still containing defects concealed above ceilings, within risers, or inside a complex sequence of valves and connections. Once the system is placed into clinical service, those defects may only become visible when a patient depends on the supply. The strengthened approach clarifies the assurance sequence. Design defines what the system must achieve. Installation creates a physical system. Engineering validation and verification then confirm that the installation aligns with the design intent and performs correctly. Separate pharmaceutical quality-control testing confirms that the medicinal gas delivered through the system meets the required quality before the relevant sections are released for use. That distinction between engineering verification
and pharmaceutical quality matters. The engineer can demonstrate pressure, flow, identity, alarm operation, valve function, and other engineering requirements, but medical gases are medicines. The final assurance chain therefore needs appropriate pharmacy and QC input alongside engineering evidence. Neither discipline is replaced by the other. The more robust process also improves handover.
Test results, material information, drawings, design assumptions, and commissioning evidence should not be treated as temporary project paperwork. They form part of the technical file and the wider golden thread of information that future APs, designers, maintainers, and governance teams may need when the system is modified or investigated years later. This is ultimately a patient-safety issue. If an
organisation cannot demonstrate what was installed, what was tested, what performance was achieved, and what limitations were accepted, it inherits uncertainty. Part A’s stronger validation, verification, and information requirements are intended to reduce that uncertainty before the system becomes operational.
Figure 2: Liquid Oxygen Supply example.
Rob McCrea
Rob McCrea has worked within the Medical Gas Pipeline Systems (MGPS) industry since 1986, gaining extensive experience with several specialist companies before establishing his own business in 1994. A recognised MGPS specialist and Expert Witness, Rob acts as an Authorising Engineer (MGPS) for both NHS organisations and the Ministry of Defence and is an author of HTM 02-01:2026.
October 2026 Health Estate Journal 65
Page 1 |
Page 2 |
Page 3 |
Page 4 |
Page 5 |
Page 6 |
Page 7 |
Page 8 |
Page 9 |
Page 10 |
Page 11 |
Page 12 |
Page 13 |
Page 14 |
Page 15 |
Page 16 |
Page 17 |
Page 18 |
Page 19 |
Page 20 |
Page 21 |
Page 22 |
Page 23 |
Page 24 |
Page 25 |
Page 26 |
Page 27 |
Page 28 |
Page 29 |
Page 30 |
Page 31 |
Page 32 |
Page 33 |
Page 34 |
Page 35 |
Page 36 |
Page 37 |
Page 38 |
Page 39 |
Page 40 |
Page 41 |
Page 42 |
Page 43 |
Page 44 |
Page 45 |
Page 46 |
Page 47 |
Page 48 |
Page 49 |
Page 50 |
Page 51 |
Page 52 |
Page 53 |
Page 54 |
Page 55 |
Page 56 |
Page 57 |
Page 58 |
Page 59 |
Page 60 |
Page 61 |
Page 62 |
Page 63 |
Page 64 |
Page 65 |
Page 66 |
Page 67 |
Page 68 |
Page 69 |
Page 70 |
Page 71 |
Page 72 |
Page 73 |
Page 74 |
Page 75 |
Page 76 |
Page 77 |
Page 78 |
Page 79 |
Page 80 |
Page 81 |
Page 82 |
Page 83 |
Page 84 |
Page 85 |
Page 86 |
Page 87 |
Page 88 |
Page 89 |
Page 90 |
Page 91 |
Page 92 |
Page 93 |
Page 94 |
Page 95 |
Page 96 |
Page 97 |
Page 98 |
Page 99 |
Page 100 |
Page 101 |
Page 102 |
Page 103 |
Page 104 |
Page 105 |
Page 106 |
Page 107 |
Page 108 |
Page 109 |
Page 110 |
Page 111 |
Page 112 |
Page 113 |
Page 114 |
Page 115 |
Page 116 |
Page 117 |
Page 118 |
Page 119 |
Page 120 |
Page 121 |
Page 122 |
Page 123 |
Page 124 |
Page 125 |
Page 126 |
Page 127 |
Page 128 |
Page 129 |
Page 130 |
Page 131 |
Page 132 |
Page 133 |
Page 134 |
Page 135 |
Page 136 |
Page 137 |
Page 138 |
Page 139 |
Page 140 |
Page 141 |
Page 142 |
Page 143 |
Page 144 |
Page 145 |
Page 146 |
Page 147 |
Page 148 |
Page 149 |
Page 150 |
Page 151 |
Page 152 |
Page 153 |
Page 154 |
Page 155 |
Page 156 |
Page 157 |
Page 158 |
Page 159 |
Page 160 |
Page 161 |
Page 162 |
Page 163 |
Page 164 |
Page 165 |
Page 166 |
Page 167 |
Page 168 |
Page 169 |
Page 170 |
Page 171 |
Page 172 |
Page 173 |
Page 174 |
Page 175 |
Page 176 |
Page 177 |
Page 178 |
Page 179 |
Page 180 |
Page 181 |
Page 182 |
Page 183 |
Page 184 |
Page 185 |
Page 186 |
Page 187 |
Page 188
