CO Alarm Consultation

The BSS very much appreciates the time and effort taken by everyone who read through the proposals and those who went on to make comments about them. Thank you. The BSS Management Committee have reached a decision.

A pdf version of the original consultation document can be viewed or downloaded here: [LINK]

A pdf version of the BSS reponse to the consultation can be viewed or downloaded here: [LINK]

Section 1 – Foreword and introduction

The Boat Safety Scheme (BSS) ran a public consultation on proposals that have the full support of its stakeholder and management committees.

The proposals are to introduce mandatory BSS Requirement for suitable carbon monoxide (CO) alarms in good condition and in suitable locations on all classes of boat in scope of the BSS Requirements with accommodation spaces.

The consultation covered all classes of BSS examination, private boats, boats used for hire and other non-private boat classes.

The BSS believes the proposals are both necessary and proportionate risk controls and your submitted comments were welcomed as very useful. The consultation ran from 17 August to 9 November 2018.


Section 2 – Background to the consultation

2.1 What is CO and why is avoiding CO poisoning essential?

CO is a highly poisonous gas that weighs about the same as air.

It is produced when carbon-based fuels used in engines and appliances, such as gas, LPG, coal, wood, paraffin, oil, petrol and diesel don't burn completely.

It can build-up on a boat with one, or a mix of these factors; faulty, badly maintained, or misused appliances; exhaust fumes from a boat's engine or generator; escaped flue gases from solid fuel stoves; shortage of oxygen - fuels need the right amount of air supply to burn completely.

It cannot be seen, smelt, tasted, or felt, (it's known as the silent killer) and only suitable CO alarms can warn of its presence reliably.

In humans and pets, CO replaces the oxygen in the bloodstream, preventing essential supplies to body tissues, hearts, brains and other vital organs. At high concentrations, CO can kill without warning, sometimes in only minutes.

Where victims survive severe CO poisoning, they can be left with long-term brain damage such as poorer concentration, or causing mood swings, etc.

Exposure to CO over a longer period, can also result in serious effects such as memory problems and difficulty concentrating.

Some people will be affected much more quickly, including: pregnant women and unborn babies; babies and young children; older people; people with respiratory problems or heart conditions.

Other people may be at higher risk too, such as those who have been doing something active and are breathing more rapidly and deeply and have a greater need for oxygen. People who have been drinking heavily may also miss early signs of problems because the symptoms may be masked.

More on CO its causes, its effects and how to prevent it can be found at

2.2 Why now were mandatory new BSS Requirements being considered?

In the past two years new information about the potential risk to boaters presented by CO has brought the need for action into focus. From the recent evidence collected, people and their pets aboard their own boats are at medium risk of CO poisoning from sources of CO generated outside of the boat by others e.g. the use of engines and appliances on adjacent boats.

The recently identified potential risk cannot be controlled by boat owners themselves. The risk is enhanced by the fact that CO is a hidden danger.

The circumstances fall within the remit of the Scheme to have in place measures that protect boat owners from the activity of others. In these circumstances a mandatory new BSS Requirement is warranted, as opposed to an ‘Advice check’.

A detailed assessment of the risks was carried out through the BSS support committees and the supporting detailed risk review report is available on the BSS website CO Alarm consultation pages.

However, it is important to stress that an essential part of owning a boat is both understanding and then addressing any risks that could arise, including CO. An understanding of CO should prevent misuse of alarms. The BSS will continue to work with partner organisations to promote education and awareness about CO, its causes, how to avoid CO and recognising the symptoms of CO poisoning.  

2.3 About the responses

In total 259 responses were received, including 7 by email; none were received by post. There was strong support for the changes demonstrated in the responses to the consultation with 84% in favour of introducing a requirement for suitable working carbon monoxide (CO) alarms.

There were a numbers of comments that raised, often individual or specific context, additional queries about the location or numbers of alarms needed to meet the proposed checks as written.

The BSS office has drawn on the Risk Review and Assessment Paper (RRAP), the original consultation document, discussions at the BSS Advisory Committee and BSS Technical Committee and additional information drawn from our competent advisors to consider to those comments.

The BSS has prepared a document that covers the specific comments made during the consultation in the context of the questions asked.

To make the response more readable and cohesive we have taken a collated approach to some of the comments. There were many with common or related themes. Where this has happened, we have paraphrased the points to get to the essence of the issue or issues in the comments.

BSS reponse to the consultation [LINK]

Section 3 – Conclusion and decisions

The BSS Management Committee has considered recommendations from the BSS Advisory and BSS Technical Committees, which also looked at responses to this consultation.

It has concluded that new BSS Requirements for carbon monoxide (CO) alarms on all boats in scope BSS Requirements with accommodation will be introduced from next April.

It also has asked the BSS Technical Committee to consider responses pointing to the need for further clarification particularly concerning the placing and number of alarms needed.

The checks, with any revised wording to ensure that the requirements are entirely clear, will be published in late January or early February 2019.

Mandatory checks will then start in April 2019 for suitable CO alarms in good condition and in appropriate locations. The requirements are designed to keep people on and around boats safe.

As well as protection from neighbouring boats, the CO alarms are also expected to prevent death or injury to boat owners from their own boat engines or appliances.

The alarms will warn people in the area about immediately dangerous levels of CO. They can also alert craft occupants to moderate levels of CO, which can be a long-term threat to health if left undetected.

The BSS Committees want to thank all the contributors to the consultation. The comments and views have been exceptionally valuable and have caused us to reflect a little longer before publishing the checks in order.

It is encouraging that so many contributors already enjoy the protection of CO alarms, however if you are yet to be protected, please see the list of CO alarms recommended as suitable for boats by the manufacturers’ body on the BSS Stay Safe pages:

5.4 Contact details for queries

Please call or contact us by phone, email or through social media at or call 0333 202 1000.

BSS CO Alarm Query, Boat Safety Scheme, National Waterways Museum Ellesmere Port, South Pier Road, Ellesmere Port Cheshire CH65 4FW