Start with the dust class. L-Class units are for general dust and debris. M-Class units are for harder-hitting dust from wood, concrete, brick and mortar. HSE construction dust guidance (CIS36) recommends an H or M-Class extraction unit for cutting and sanding wood, chasing concrete, drilling masonry and clearing rubble, and lists L-Class only for sanding plasterboard jointing. It also says not to use a general commercial vacuum for on-tool extraction. In this range the JCB Professional 45L (JCB-PVACP-45M) is the M-Class model.

Match the tank to the job. The 23L HEPA model (JCB-VACP-23H) weighs 5.1kg and suits van work and small clean-ups. The 30L stainless steel and 34L Silent Pro models cover most workshop and fit-out work. The 61L Silent Pro (JCB-SVACP-61L) is for big clear-ups and liquids, with a low-level drain and a 64mm hose for bulky debris.

Check noise and reach. The three Silent Pro models run at 65dB(A); the 23L and the 45L M-Class run at 80dB(A). Total reach from the socket runs from about 7.2m on the 23L to about 13.2m on the 45L, which has a 7.5m cable and a 5.2m anti-static hose.

For liquids, look at the cut-out and drain. The 23L uses a ball float that blocks airflow when the tank is full. The 45L stops automatically with a red light and buzzer. The 30L and 61L have tank drains for emptying collected water.

The 18V handheld (21-18VAC-B) is for dry debris only and is sold as a bare unit. It runs on JCB 18V batteries.