| Requirement | Justification | Specification | Justification |
1. The device must stay secure for a clinically acceptable period. | It is necessary to ensure the device does not leak and adapts to daily usage. | Must be able to withstand a displacement force of 25.51 ± 17.90 lbs for 24 hours. | The attachment site component needs to be changed every 24 hours for sanitary purposes while accommodating daily usage. |
| 2. The Device Must Collect Urine Outputs. | Minimizes patient cleaning efforts for nursing staff, and ensures that patients are staying dry, and urine outputs are accurate. | Can collect a flow rate of 4.5-21.6 mL/sec for up to a minute. | Uroflowmetry indicates these values to be the normal ranges for a urination cycle among males. |
| 3. Can accommodate 95% of males. | The device can be used for at least 95% of male patients who would benefit. | Can accommodate 6-16.5 cm in length, and 7.5-13.5 cm in girth. | The range includes 95% of penis sizes; 6-12.5cm in length and 7.5-11 cm girth for flaccid, and 10-16.5cm in length and 9.5-13.75 cm girth erect. |
| 4. Clinical staff must be able to easily collect a clean urine sample from the canister. | Allows urine samples to be obtained for urinalysis. | The urine collection point is sterile (SAL 10-6), and the device provides a non-mixed sterile sample that was voided less than 1 hour ago. | Prevents urine sample contamination via the device, and provides an adequate sample for urinalysis (mixed samples and samples over 1 hour old are not used for urinalysis unless refrigerated). |
| 5. Must provide a warning to clinical staff when the canister is full. | Allows clinicians to empty the canister before a leakage event since urine is considered a biohazard. | Detect volume between 0 – 2000 ml ± 50 ml at any arbitrary time, then trigger an alarm to alert staff. | 2000ml is the full canister volume and an overflowing urine canister is a biohazard. |
| 6. The device must be able to regulate the negative pressure based on the urination cycle. | Necessary to reduce vac-related injuries and improve patient/user comfort. | Turn on negative pressure from 40-80 mmHg ±5 mmHg using a urination sensor. | Current vac-assists operated 40-80 mmHg. |
| 7. The device must ensure proper house vacuum settings. | Necessary that clinical staff does not set vac to outside the accepted range. | Detect negative pressure set to >80 mmHg or <40 mmHg ± 5. | Negative pressure >80 mmHg or <40 mmHg is outside the acceptable range. |
| Requirement | Specification |
| 8. The collected volume must be visible to clinical staff. | Contains measuring lines per every 50 mL or digital display of volume ± 50 ml. |
| 9. The canister must hold normal urine volume output during the clinically relevant time. | 2000 ml to accommodate the upper range. |
| 10. Must pass electrical safety standards for hospital-based systems. | 500 microamps for leakage current, and less than 0.1 ohms for ground resistance (IEC 6060). |
| 11. The device captures 90% of moisture passing to the vacuum. | The device captures 90% of moisture passing to the vacuum[13]. |