MDR Annex I §17.1 requires medical devices that incorporate electronic programmable systems to be designed to ensure repeatability, reliability, and performance in line with their intended use under the foreseeable conditions of use. EN 60601-1 operationalises this through environmental test clauses. The IEC 60068 series provides the underlying test methods for climate, vibration, and shock. Environmental testing is where "works on the bench" meets "works in a paramedic's bag on a cold Tuesday."

By Tibor Zechmeister and Felix Lenhard.

TL;DR

  • MDR Annex I §17.1 requires electronic programmable systems to deliver repeatable, reliable performance under foreseeable conditions — and foreseeable means more than a controlled lab.
  • EN 60601-1 includes environmental requirements for medical electrical equipment covering operating, transport, and storage conditions, and references temperature, humidity, and atmospheric pressure ranges.
  • IEC 60068 is the horizontal environmental test method standard family used to cover climate cycling (dry heat, cold, damp heat, temperature change), vibration, and shock.
  • The test plan depends on the use environment: hospital, ambulance, home, outdoor, sterilized and reprocessed.
  • IP rating (IEC 60529) covers ingress of solids and liquids and is separate from but often bundled with environmental testing.
  • Building the environmental test plan in design input prevents the expensive late-stage discovery that your device does not survive a European winter transport.

Why this matters

A portable ultrasound startup in Vienna passed EN 60601-1 electrical safety on the first attempt. They were proud. Two weeks later the same device went into the climate chamber for transport conditioning (-25 C for 16 hours, per the test plan they copied from a similar device). When it came out, the LCD was cracked, the battery would not charge, and the firmware had locked up. Three months of rework. The problem was not the testing — the testing worked exactly as intended. The problem was that no one on the team had asked, during design, "what happens to this device in a van in February?"

Environmental testing is the translator between the intended purpose you wrote on page one of the technical file and the physical reality of where the device will actually live. Skip it, and you ship a device that fails in the field. Plan it late, and you rework mechanical and electrical decisions after they are frozen. Plan it early, and it becomes a checklist.

What MDR actually says

MDR (EU) 2017/745 does not specify environmental test levels. It sets the principle and defers to harmonised standards for the method.

Annex I §17.1 states that devices incorporating electronic programmable systems (including software that is a device in itself) shall be designed to ensure repeatability, reliability, and performance in line with their intended use. In the event of a single fault condition, appropriate means shall be adopted to eliminate or reduce as far as possible the consequent risks or impairment of performance.

Annex I §14 (already discussed in our electrical safety post) requires devices to be designed and manufactured in such a way that the risks linked to their use in conjunction with the environment, and to the materials and substances used, are removed or reduced.

The phrase that carries the most weight in practice: "intended use under foreseeable conditions." Foreseeable is the auditor's lever. If your intended purpose says the device is for use in emergency medical services, then cold cabins, vibration from vehicle transport, and rough handling are foreseeable. If you did not test for them, you did not meet §17.1.

EN 60601-1 environmental clauses

EN 60601-1:2006+A1+A12+A2+A13:2024 covers environmental conditions in several places:

  • Operating conditions: temperature, humidity, and atmospheric pressure ranges that the device must meet its essential performance within.
  • Transport and storage conditions: separate, usually wider, ranges that the device must survive (without operating) and then perform normally.
  • Mechanical tests: drop, bump, impact, push, and related mechanical stress tests for portable and transportable equipment.
  • Ingress protection: reference to IEC 60529 IP rating where claimed.

The specific levels depend on the declared use environment. A device declared for home use (EN 60601-1-11) has different requirements than one declared for professional healthcare facility use only.

IEC 60068 — the method toolbox

IEC 60068 is a horizontal standard series (not medical-specific) that defines how to run environmental tests. Relevant parts include :

  • IEC 60068-2-1: Cold (low temperature exposure).
  • IEC 60068-2-2: Dry heat.
  • IEC 60068-2-6: Vibration, sinusoidal.
  • IEC 60068-2-14: Change of temperature (thermal cycling).
  • IEC 60068-2-27: Shock (mechanical shock pulses).
  • IEC 60068-2-30: Damp heat, cyclic.
  • IEC 60068-2-64: Vibration, broadband random.

EN 60601-1 calls out IEC 60068 methods for specific tests. Your test lab will build the test plan by cross-referencing the EN 60601-1 requirements against the applicable IEC 60068 methods and the use environment you declared.

A worked example

A portable vital signs monitor intended for ambulance and emergency department use, Class IIa, battery-powered, with a BLE connection to a receiving tablet.

Declared use environment: - Operating: 0 C to 40 C, 15 to 95 percent relative humidity non-condensing, 700 to 1060 hPa. - Transport and storage: -25 C to 70 C, 10 to 95 percent relative humidity, 500 to 1060 hPa. - Vehicle-mounted and handheld in moving ambulance. - Outdoor use on scene (rain, wind).

Environmental test plan built against EN 60601-1 and IEC 60068:

  1. Climate conditioning — operating limits. Place device in chamber at each corner of the operating range. Verify essential performance (accurate SpO2, pulse rate within tolerance, display readable, alarms functional) at each corner. Methods drawn from IEC 60068-2-1 (cold), -2-2 (dry heat), -2-30 (damp heat cyclic).

  2. Climate conditioning — transport extremes. Expose non-operating device to -25 C for 16 hours and +70 C for 16 hours. Return to operating conditions. Verify full performance. This is where the Vienna ultrasound story killed the prototype.

  3. Thermal cycling. Per IEC 60068-2-14, ramp between transport extremes multiple cycles to reveal solder joint fatigue, adhesive failures, and differential expansion problems.

  4. Vibration — transport. Per IEC 60068-2-6 or -2-64, apply vibration profile representative of vehicle transport. For ambulance use, a vehicle vibration profile (ISTA or MIL-STD-810 equivalents are sometimes used) may supplement the EN 60601-1 requirement.

  5. Mechanical shock — drop and bump. Per EN 60601-1 clause 15.3 (or equivalent), the handheld portable device must survive defined drop heights onto a hard surface without creating a safety hazard. For handheld equipment, typical drop heights are one metre.

  6. Ingress protection. If the device claims IPX4 (splash), test per IEC 60529. Map the IP rating claim back to foreseeable use (on-scene rain).

  7. Combined stress. For critical devices, combined environmental plus vibration (climate chamber with shaker) reveals failures that single-stress tests miss. Not always required by EN 60601-1 but increasingly used for devices in harsh use environments.

Result integration. Every test runs a pre-test functional check, the environmental exposure, and a post-test functional check. Essential performance must be maintained throughout (where required) or restored after (where only survival is required). The test report becomes part of the technical documentation under MDR Annex II.

Risk management hook. Under EN ISO 14971:2019+A11:2021, each environmental hazard (cold start, humidity ingress, drop during use, vehicle vibration) is a distinct entry in the risk analysis. The environmental test evidence is the verification of the risk control.

The Subtract to Ship playbook

1. Write the use environment in design input. Before any test planning, write a paragraph that describes, concretely, where the device will be used, transported, stored, and cleaned. Include temperature ranges, humidity, altitude, mechanical stresses, user handling, and any reprocessing. This document drives the entire environmental test plan.

2. Pick your EN 60601-1 particulars early. EN 60601-1-11 (home healthcare) has different environmental requirements than EN 60601-1-2 (EMC) or EN 60601-2-xx particulars for specific device types. The particular standards inherit and modify the general requirements. Which ones apply depends on declared use.

3. Plan environmental testing to run in parallel with electrical safety. Same lab, same samples, same planning cycle. A combined EN 60601-1 campaign saves weeks versus sequential testing.

4. Build mechanical margins into industrial design. If you know drop and vibration are coming, you design housings, brackets, and connector retention for it. Retrofitting impact resistance onto a failed prototype is expensive.

5. Test with representative software and settings. Environmental tests that use demo firmware produce demo reports. Load the production firmware, configure the production settings, and run with production accessories.

6. Document test failures honestly. A test failure discovered and fixed in pre-compliance testing is a strength. A test failure hidden from the report is a future nonconformity or field incident. Keep the failure log as part of the design history file.

7. Trace every environmental test to a risk control. Under EN ISO 14971, the test is not the point — the risk control is. The test proves the control works. Your risk management file should cross-reference each environmental test report to the hazard it verifies.

8. Do not overbuild. Testing to aerospace levels for a hospital-only device is waste. Test to the declared use environment with appropriate margin. The MDR requires "foreseeable" conditions, not every conceivable one.

Reality Check

  1. Is the declared use environment (temperature, humidity, altitude, mechanical stress, reprocessing) written in design input and traceable to the intended purpose?
  2. Does your environmental test plan cover operating limits, transport and storage limits, thermal cycling, vibration, and drop — with a justified exclusion for any test you are not running?
  3. Have you identified which EN 60601-1 particular standards (for example EN 60601-1-11 for home use) apply to your device?
  4. Is your IP rating claim (if any) tested per IEC 60529 with the result referenced in the label and instructions for use?
  5. Are environmental hazards explicit entries in your EN ISO 14971 risk management file, with test reports as verification evidence?
  6. Does your test plan include a functional check before and after each environmental exposure, using production firmware and settings?
  7. Do you have sufficient prototype samples to run the test plan without cannibalising samples across tests in ways that invalidate results?
  8. If your device fails an environmental test in week 11 of development, is there enough schedule margin to redesign, rebuild, and retest before your Notified Body submission?

Frequently Asked Questions

Is environmental testing mandatory for every medical device? Yes in principle. MDR Annex I §17.1 applies to any device with electronic programmable systems, and Annex I §14 applies to all devices regarding environmental interactions. The scope and depth depend on device type and use environment. A stationary MRI and a handheld paramedic tool need very different test plans.

Can I skip vibration testing for stationary equipment? Transport vibration still applies. Even a stationary device is transported from the factory to the hospital. The transport condition requirements in EN 60601-1 and the particular standards typically include vibration and shock simulation for distribution.

How does IP rating relate to environmental testing? IP rating (per IEC 60529) tests ingress protection — dust and water. It is a specific subset of environmental testing and appears on the label. If you claim IPX7 (immersion), you must have test evidence supporting it, and you must honour it in your instructions for use.

Do I need to repeat environmental tests for software updates? Not usually. Environmental tests verify the hardware platform. Software updates that change essential performance or change the risk profile may trigger targeted re-verification, but not a full re-test campaign. Document the rationale in your change control process.

What about drop testing with patient accessories attached? If accessories can reasonably be connected during use and drop scenarios include those configurations, test in the connected state. The drop test verifies that the device does not become a hazard during foreseeable use.

How does environmental testing interact with biocompatibility? They are independent. Biocompatibility (EN ISO 10993-1:2025) covers patient-contacting materials and is unaffected by environmental testing. But if environmental stress could change a material's leachables profile (for example high-temperature storage of a polymer that contacts skin), the risk analysis should link the two.

Sources

  1. Regulation (EU) 2017/745 on medical devices, consolidated text. Annex I §14, §17.1.
  2. EN 60601-1:2006+A1+A12+A2+A13:2024 — Medical electrical equipment — Part 1: General requirements for basic safety and essential performance.
  3. IEC 60068 series — Environmental testing — methods for climate, vibration, and shock (editions to be cited per specific part applied).
  4. EN ISO 14971:2019+A11:2021 — Medical devices — Application of risk management to medical devices.