The construction industry is dangerous, with 39 fatalities at work in the UK in 2012/13 and comparable and even larger figures reported worldwide. People also take part in construction on a voluntary basis; most volunteers have limited training and no technical qualification, whilst safety regulation frameworks range from being comparable to professional sectors to zero regulation in some international contexts. Unstructured interviews were undertaken with volunteer construction workers from two areas; those returning from international development projects and those regularly volunteering on UK heritage railways. Taking a social constructionist perspective, data were explored using discourse analysis to illuminate 'safety' within this unique construction 'industry'. Those with engineering or technical backgrounds developed more tangible constructions of safety, around risks and hazards, within their activities, yet volunteers without this experience also acknowledged a wider context of danger. Volunteers on overseas projects developed discourses of 'difference' between safety at home and safety outside of the UK; associated with negative practices overseas yet with acceptance of their inevitability as part of the voluntary experience. Further work is proposed to determine whether these insights can contribute to improved safety management within the voluntary construction context.