There is no single event ratio that fits every rental. Send peak users, hours, existing facilities, and the layout. For construction, use the applicable OSHA fixture baseline and plan cleaning separately.
Start with people present at the same time
For a Corpus Christi project, count the busiest shift, including overlapping trades. For a public or private event, include staff and vendors alongside guests. Record the hours facilities will be needed and which permanent bathrooms everyone can actually use. A total guest list or a building’s advertised capacity does not provide that information by itself.
For construction, check the fixture baseline
OSHA 1926.51(c), Table D-1, establishes construction sanitation baselines. One facility is listed for 20 or fewer workers; larger crews use toilet-seat and urinal ratios. A 60-worker example calls for two seats and two urinals. Review the standard, its exceptions, and washing requirements with the site manager. A minimum fixture count does not tell you how often equipment must be cleaned.
For events, describe the program and layout
A wedding reception with a fixed guest group differs from an open waterfront program with changing attendance. Send peak attendees, duration, food and drink service, and separate activity areas. The team needs those details to recommend equipment. Construction ratios are not an event-sizing formula, and another festival’s order is not a reliable template for yours.
Plan accessible groups and routes together
For covered portable-toilet clusters, the Access Board guide calls for at least 5% accessible units. Round up within each group: ten units require at least one, while thirty require at least two. Verify applicability and the documented model. A suitable unit also needs a usable approach; sand, soft ground, curbs, or a blocked entrance can prevent access.
Send a brief that can become a quote
Combine the address, peak people, hours, existing facilities, layout, and service window in one request. For a city venue, coordinate the proposed positions with the Corpus Christi event contact. Ask the rental team to include quantity, cleaning, washing supplies, and any extra visits in the written recommendation. Revisit the plan when attendance, shifts, or operating hours change.