Table 1 Mapping the smoke-free home intervention delivery to the Behavior Change Wheel

Barriers identified using the Capability, Opportunity, Motivation, Behavior (COM-B) model

Intervention functions (layer 2)

Policy targets (layer 3)

PSH resident barriers and potential enablers

-Have decreased knowledge of SHS or thirdhand smoke (capability)

-Lack skills to adopt a smoke-free home (capability)

-Indoor cannabis use and other substance use reduces capability and motivation to smoke outdoors (capability/motivation)

-^aKids/pets may encourage smoke-free home adoption (motivation)

- Lack of safe designated smoking zones reduces opportunity for smoke-free living (opportunity)

- Social norms of pervasive smoking reduces opportunity for smoke-free home (opportunity)

PSH residents

-Education: Information on harms related to SHS and thirdhand smoke; combustible tobacco and e-cigarettes, and cannabis

-Training: Step-by-step guide to adopt a smoke-free home

-Restrictions: Voluntary smoke-free home adoption

-Persuasion: Pledges; infographics on impact of SHS on kids and pets

-Enablement: Referral to smoking cessation resources

Environmental or social planning

-Voluntary adoption of smoke-free homes

-Exploring potential downstream effect of other residents adopting smoke-free homes

Service provision

-Providing referrals to cessation programs

PSH staff barriers

-Believe residents prefer to smoke indoors (capability)

-Have no skills to refer residents to smoking cessation programs (capability)

-Believe that smoking can allay a resident’s mental health symptoms (capability)

PSH staff

-Training: To refer residents to smoking cessation programs

-Education: Information from pilot data that residents are supportive of indoor smoke-free policies; debunk myths around nicotine allaying mental health symptoms