Martyn's Law, explained.

Introduced following the 2017 Manchester Arena attack, Martyn's Law improves public safety through proportionate preparedness, staff awareness and protective security measures at publicly accessible premises.

Publicly accessible premises and events where members of the public may be present. Typical examples include:

Education settings are treated slightly differently — read our guide to Martyn's Law for schools and colleges.

Focused on preparedness rather than physical security investment. Duty holders must have:

• ✓Procedures for evacuation
• ✓Procedures for invacuation (moving people to safer internal locations)
• ✓Procedures for lockdown
• ✓Procedures for communicating with staff and visitors during an incident
• ✓Relevant staff trained in these procedures

In addition to Standard Tier obligations, Enhanced Tier organisations must:

• ✓Undertake terrorism vulnerability assessments
• ✓Consider reasonably practicable security measures
• ✓Consider reducing vulnerabilities and the impact of an attack
• ✓Maintain documented plans and records
• ✓Provide information to the SIA if required

There is no requirement to implement every possible measure. The legal test is whether measures are "reasonably practicable" for that venue.

The Act also applies to certain temporary events — festivals, outdoor concerts, sporting events, public celebrations and temporary entertainment venues. Where attendance exceeds 800 persons, organisers may fall within the Enhanced Tier.

The Security Industry Authority maintains notification systems, issues guidance, monitors compliance, investigates breaches, and takes enforcement action where necessary. Businesses must demonstrate they have considered terrorism preparedness and implemented proportionate measures.